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Биология

ЕГЭ подготовка

ЕГЭ

биология ЕГЭ

Биология ЕГЭ с нуля

биология егэ 2 часть

Рохлов

егэ фипи

биология егэ теория

биология ЕГЭ задание

Алена Клименко

биология егэ подготовка

демоверсия

демоверсия биология

клетка

химический состав клетки

микробиология

биология егэ

егэ биология

00:00:05

hi hello guys I’m

00:00:07

very glad to see you all and but today is the

00:00:10

last lesson of this month but I

00:00:13

still have some feeling like you know

00:00:15

what you’re missing on

00:00:18

protein biosynthesis and

00:00:20

you know what you’re missing lie down task

00:00:22

1 hour type of protein biosynthesis so on

00:00:25

Tuesday I I will hold an open webinar,

00:00:27

it will be for everyone, but first of all, Ivan will

00:00:29

wait for his students and we will

00:00:32

solve the tasks of the

00:00:33

first part on protein biosynthesis, how do you like

00:00:37

this idea, if you like it,

00:00:39

write something in the comments and

00:00:42

I will be very glad to see you all if you

00:00:44

can’t this is the time, well, the phase, after all,

00:00:47

you are calculating your time, you can

00:00:49

look at the recordings later, well, of course, I

00:00:52

will always be glad to see you that you

00:00:54

answered questions with me

00:00:57

so before the regulation of protein biosynthesis, we in

00:01:01

practice at the very end yesterday discussed what is

00:01:04

here there is one regulator it

00:01:07

synthesizes it encodes a repressor protein,

00:01:10

for example, this repressor protein

00:01:12

attaches to a structural gene and

00:01:16

this structural gene stops

00:01:17

being expressed, that is, it stops

00:01:19

working what time is it

00:01:21

always at 5 o’clock always at 5

00:01:24

o’clock who can’t look at the recording

00:01:27

guys, it’s okay,

00:01:30

but be sure to look like

00:01:32

this ok,

00:01:36

well, today we are moving on to a very

00:01:40

very delicate topic, I started

00:01:42

gametogenesis, we’ll see, then

00:01:43

we’ll look at embryogenesis and look at the embryo

00:01:46

too,

00:01:47

and

00:01:49

so gametogenesis, what is a gamete,

00:01:54

again on Tuesday we will look at the

00:01:57

task 1 hour, type of protein biosynthesis,

00:02:02

so x guys, what is a gamete gamete this is a

00:02:07

germ cell

00:02:13

here gametes sex cells

00:02:20

sex cells

00:02:22

sex cells what are the types

00:02:26

of eggs these are usually female sex

00:02:30

cells

00:02:33

there are sperm and

00:02:40

sometimes all with perm

00:02:43

remember how they differ from permeate

00:02:46

sperm in sperm unlike

00:02:48

sperm are immobile

00:02:51

and

00:02:54

sperm are motile in sperm we can

00:02:57

find in some plants sperm and

00:03:00

are found only in gymnosperms,

00:03:01

angiosperms, and

00:03:08

angiosperms, sperm in all others, there is

00:03:11

still such a moment in males, now

00:03:15

we’ll talk specifically about animals, in

00:03:17

males, gametes develop in the testes, and

00:03:20

in females, gametes, these cells develop in the

00:03:24

ovaries, and now we will talk to

00:03:26

you about the

00:03:27

formation of gametes specifically in animals

00:03:31

because in plants there all gametes are

00:03:34

generally formed by mitosis and all the words

00:03:37

gametogenesis let’s analyze its gametes, we already

00:03:40

know that these are sex cells din with

00:03:42

genesys always means that something is

00:03:44

formed genesis the formation of something

00:03:54

so that means there will be the formation of

00:03:56

sex cells let's look at these processes,

00:03:58

gametogenesis can be divided into

00:04:01

spermatogenesis

00:04:02

when guess what

00:04:06

sperm are formed, it is clear from the name itself

00:04:08

and Avagyan with here about the vagina,

00:04:12

eggs are formed in another way Avagyan with you can be

00:04:15

called again - with this synonyms you can

00:04:19

say so so then don’t ask

00:04:22

me about one of can I say it again -

00:04:25

s

00:04:26

thank you very much

00:04:29

Dasha thank you so now let’s analyze separately the

00:04:35

spermatogenesis of Homer her and Avagyan s and

00:04:38

compare them with each other

00:04:40

spermatogenesis it all starts with the primary

00:04:44

germ cell, here it is the

00:04:47

primary germ cell it has a set of

00:04:50

chromosomes 24 c as if it already has

00:04:54

replication occurred then this is the primary

00:04:57

germ cell, we will call

00:05:00

it for short p p k divides by mitosis divides by

00:05:03

mitosis once the sperm of that one is obtained

00:05:06

not with a set of chromosomes two n 20 these

00:05:11

sperm of that one do not divide a second time but

00:05:14

pay attention to this sperm of that

00:05:16

one to enter into a new mitosis you

00:05:20

still need to double the genetic information,

00:05:22

so right before mitosis, the sperm of that one does

00:05:25

not become two 4c, this is possible, that

00:05:30

is, in fact, the sperm of that does not happen 2 in

00:05:31

2 c puts on two people 4c, depending on what

00:05:35

period of life you look at them, before

00:05:37

replication or after, but most often on the Unified State Exam

00:05:40

they write exactly like this, but I’ll show you

00:05:43

one task where you have to write

00:05:45

exactly like that, well, in the end we got

00:05:49

four sperm from that unknown thief of chromosomes

00:05:51

two n 20 then these sperm from that one

00:05:56

get into the growth zone and a

00:06:00

first-order spermatocele is formed a

00:06:04

first-order spermatocele has a

00:06:07

set of chromosomes 2 and 4 c, that is,

00:06:09

replication has already occurred here, then this

00:06:12

spermatocele is growing, growing, due to

00:06:15

what, due to what, it will increase

00:06:17

in size, what needs to be done in general,

00:06:21

as with a person, when a person grows or

00:06:24

increases in size, it’s

00:06:26

okay when a person this is another

00:06:28

multicellular thing that is growing well, it is the

00:06:30

spermatocele for it to grow there must

00:06:32

be more content, so to speak, it

00:06:36

needs to synthesize more

00:06:38

nutrients Nastya is absolutely

00:06:40

right, it needs to create more

00:06:42

nutrients

00:06:43

due to this it grows and

00:06:46

increases in size, that is, essentially

00:06:49

replication occurs in the growth zone and in

00:06:52

general, the interphase is actively proceeding,

00:06:57

taking into account the interphase occurs then

00:07:01

this is already number 2 sperm of the first

00:07:05

order, that is, it was the primary germ

00:07:07

cell, then the sperm to go will not give

00:07:11

perma, then one is full of the first order, then

00:07:16

this spermatocele of the first order means it

00:07:19

enters mejos goes first first

00:07:22

division of meiosis

00:07:23

as a result of the first division of meiosis we

00:07:26

get two cells with a set of chromosomes

00:07:29

n2 price we form that after the first

00:07:32

division of meiosis there is a reduction in the

00:07:34

set of chromosomes but the mustache temple 2

00:07:36

ramative therefore 20 so we got

00:07:40

these cells, they are also called sperm

00:07:43

tacitus and but they are already cannot be also of the

00:07:45

first order will not be older than the

00:07:47

spermatocele of the second order, then the

00:07:50

spermatocele of the second order enters into

00:07:53

mejos 2 in the second division of meiosis and

00:07:56

there is already a divergence of these two

00:07:59

aromatic and chromosomes nadh and templetivnye

00:08:01

and we see a decrease in the amount of DNA and the

00:08:04

set of chromosomes becomes inter and

00:08:08

these cells are already called sperm tiger

00:08:12

and then these sperm ti de enter the

00:08:16

next zone it is called the zone

00:08:17

of formation here

00:08:20

the tail is simply formed due to the fact that the tail is formed

00:08:24

for called

00:08:25

formation and so spermatogenesis four

00:08:29

zones of reproduction when there is a primary

00:08:32

germ cell begins to divide mitoses and

00:08:34

we get a lot of sperm that is

00:08:37

not the next growth zone when a

00:08:40

first-order spermatocele is formed and it grows,

00:08:44

this is logical into the growth zone, tons grows

00:08:47

then the maturation zone of maturation when

00:08:50

he still needs to make his own set of

00:08:52

chromosomes so more sexual,

00:08:54

more haploid, reduce it by two

00:08:58

times then here meiosis should occur

00:09:00

1 second division and the first second

00:09:03

division refers to the zones of maturation

00:09:05

dragged along, as it were, zones of maturation two

00:09:07

stages occur the first stage when

00:09:10

the first mejos occurred and we got

00:09:12

sperm tacitus and the second order and the second

00:09:15

stage when the second meiosis occurred and

00:09:18

we got spear motives and everything and then the formation zone here are

00:09:23

your questions what you don’t

00:09:26

understand here is how to remember this we take there is the

00:09:29

same as we acted in life

00:09:31

cycles the same as we performed laughs

00:09:33

we take a leaf we

00:09:35

prescribe first by peeking

00:09:38

you can even look at the coals completely looking at the

00:09:41

webinar then close it

00:09:43

prescribe it slightly peeking then

00:09:47

close it again, draw again,

00:09:49

don’t peek, but if at some

00:09:52

point you need to look, you understand

00:09:54

that you didn’t remember it, look again

00:09:56

and so on until you can

00:09:59

draw it without peeking three or four

00:10:01

times, draw and spermatogenesis will take place

00:10:04

in your pocket everything is clear, generally a

00:10:07

fun easy topic and even logical at

00:10:09

first not like quantitatively multiplied

00:10:12

multiplied by mitosis of course this is all

00:10:14

done in the house increased in size

00:10:16

interphase and then you need to reduce the set of chromosomes

00:10:20

but they all mature that way, that

00:10:22

is, logical well

00:10:28

no primordial germ cells that’s what the

00:10:30

primary ones are called, that’s it, that’s the

00:10:32

very first one that doesn’t have a manner, it’s

00:10:35

called the primary germ

00:10:37

cell, and the sperm of that one already appears

00:10:40

after the division of the primary germ cell,

00:10:45

so

00:10:47

good now about vogue, thank you, Pasha,

00:10:51

thank you very much about everything, I’m very glad

00:10:53

that you have everything works out now both

00:10:56

genesis about the

00:10:58

buoy from the formation of eggs, here

00:11:02

everything will be very similar to spermatogenesis

00:11:04

sea from the difference, the beginning is the same zone

00:11:07

of reproduction here the primary germ cell

00:11:10

divides by mitosis and here we see that there

00:11:13

are more of them and we get

00:11:16

about a carriage with a set of chromosomes 220 now

00:11:19

each in the car enters the

00:11:23

growth zone where it increases in size

00:11:26

for

00:11:28

we get an oocyte of the first order

00:11:30

which grows in the vagina for the

00:11:33

growth zone are more pronounced than in spermatogenesis

00:11:37

spermatogenesis because the eggs

00:11:39

must contain more

00:11:41

nutrients and therefore here it grows

00:11:44

stronger than in the growth zone of

00:11:48

spermatogenesis, so

00:11:53

then this first-order oocyte

00:11:57

enters the maturation zone, and look, the

00:12:00

first difference was that the vacek

00:12:02

turns out to be larger, the second difference in the maturation zone,

00:12:07

the oocyte enters 1 mejos,

00:12:11

enters 1 mejos, and

00:12:15

here there is a difference, the

00:12:18

divergence to divide cytokinesis will

00:12:21

occur unevenly and drainage

00:12:23

of spermatogenesis cytokinesis occurred

00:12:25

evenly, half of the cytoplasm and

00:12:29

half of the cell into the other and you see it turned out 2

00:12:31

identical cells top ovo genesis of the sex

00:12:35

more than half of the cytoplasm will go into one

00:12:39

cell and just a little bit of the cytoplasm

00:12:42

will go into another cell and this is the cell

00:12:44

that received most of the

00:12:47

cytoplasm

00:12:48

most of nutrients, be

00:12:51

this the color of the second order, but this

00:12:54

second cell, a poor little one with a

00:12:57

small amount of cytoplasm of

00:12:59

nutrients, will be called a

00:13:01

polar body, also known as a director for and

00:13:05

bodies, aka reduction, these are all

00:13:08

synonyms for a director for it is also called a

00:13:13

director for and

00:13:15

or reduction

00:13:21

why couldn’t I share pores, what do

00:13:24

you think, why is Vova genesis such a

00:13:27

perversion, what was it necessary to do, so

00:13:30

this polar body will

00:13:32

not be able to become an egg in the future

00:13:35

for which the polar body sacrificed

00:13:39

all its nutrients,

00:13:41

gave everything everything here for what your

00:13:45

guess will be invented, we think

00:13:51

egg 1 yes well, this is rather a

00:13:54

drawback that women have so few

00:13:56

eggs, it would be possible to have

00:13:58

more, but what is all this for? 7 it’s

00:14:02

all for the sake of the family so that in

00:14:06

the end the egg receives just a

00:14:09

drop-dead supply of nutrients

00:14:11

so that it has a lot of

00:14:13

nutrients because the

00:14:18

future embryo will need to be fed with these nutrients until

00:14:22

it is implanted into the uterus, it will need to be

00:14:25

fed somehow,

00:14:27

but if these are some other

00:14:31

organisms in which

00:14:33

fertilization occurs in a non-organism, there in

00:14:35

general the egg should be just

00:14:37

gigantic, remember what it looks like The

00:14:39

egg of the fish there is so large that it is so

00:14:42

large

00:14:44

because in them fertilization

00:14:46

occurs generally from the outside and it is in the

00:14:48

embryo that needs to be fed; it

00:14:51

feeds on the nutrients of the

00:14:52

egg, we have smaller eggs

00:14:54

because development occurs in the uterus and the

00:14:58

embryo begins as soon as it is implanted in the

00:15:00

uterus receive

00:15:02

nutrients from the mother, so we all

00:15:04

return here, the maturation zone as

00:15:07

a result of the first meiosis, we get

00:15:09

two cells, one very large, which

00:15:12

has grabbed most of the nutrients for itself,

00:15:13

it will be

00:15:15

called this second order with a

00:15:17

set of chromosomes m2 c and the second one is from God and

00:15:20

polar bodies with a set of chromosomes n20

00:15:24

she donated her

00:15:26

nutrients further and the larger the dowry

00:15:30

when we don’t have a bride here with a

00:15:32

dowry then the second division of meiosis

00:15:36

again this second-order oocyte

00:15:40

divides again and we God again

00:15:43

unevenly and this is the egg that

00:15:46

turns out to be large

00:15:48

with large amount of

00:15:50

nutrients, but this polar body

00:15:53

is small, and this polar body is

00:15:55

also divided into two,

00:15:57

so it will be small

00:16:00

because initially the cell was small and

00:16:02

what we have as a result are both

00:16:05

genesis from the 1st cyto of the first order,

00:16:09

or you can even drip further from 1 and

00:16:12

the car we get one egg and a

00:16:17

circumpolar body, but in gamete

00:16:20

genesis from one spermatogenesis we

00:16:23

got four full-fledged

00:16:25

sperm,

00:16:27

this is the story of

00:16:29

this egg, we are also writing here either

00:16:34

with eggs because amati yes if abate yes

00:16:36

it can still happen later what

00:16:40

changes will come only then will

00:16:42

the egg cell come, but there is no formation zone here, you

00:16:46

see sperm has sperm then Guinness

00:16:49

there was a formation season when

00:16:51

the tails were formed, as you understand,

00:16:54

the eggs are east, no, they

00:16:57

have opinions, so there will be no formation zone here

00:17:00

either,

00:17:02

but this is the story here,

00:17:05

now there is

00:17:06

one more nuance where they catch children

00:17:10

just harshly v.g. in

00:17:13

most vertebrates, in the

00:17:16

second division of the meiosis of the oocyte of the second

00:17:19

order, here

00:17:22

everything stops, here everything

00:17:25

stops for us from the second order

00:17:28

and

00:17:29

when fertilization occurs,

00:17:32

the sperm fertilizes this one

00:17:34

from the second order, such an immature one, and

00:17:38

only after fertilization

00:17:40

does everything else in the process happen

00:17:43

and we we get

00:17:47

an egg in this way,

00:17:49

the sequence could be an

00:17:53

oocyte of the

00:17:55

second order

00:17:58

of fertilization and

00:18:00

only then

00:18:02

the formation of an egg,

00:18:06

this is the nuance

00:18:08

it is written in the mansion, it is stamped pink and

00:18:12

this question was in the trash, in my opinion it was

00:18:15

even at a real giga I don’t remember exactly, but

00:18:17

in a rock club it definitely there is 21 years old I’ll find it

00:18:19

later I’ll show you keep this in mind don’t confuse

00:18:23

what function the polar corpuscles perform,

00:18:27

firstly they are just like that, they

00:18:30

are formed

00:18:31

as a

00:18:33

by-product you are all such yeast, you need to

00:18:36

strip it, you need to separate it, they also

00:18:39

accept the fate they help the eggs to be

00:18:41

directed, that is, the guide on the

00:18:43

corpuscle helps on units what

00:18:45

directions in such a function are also

00:18:47

prescribed, but the most important thing is that they

00:18:49

are simply like a remnant of this and

00:18:51

the eggs,

00:18:57

so what is watts and look,

00:19:01

they can talk to you about you and about the car,

00:19:04

they can write this down as about this

00:19:08

synonyms wow

00:19:10

equals about it’s just that so, so they can

00:19:14

say no, don’t be scared,

00:19:17

now the difference is here the cell

00:19:22

grows stronger than here in ovogenisa from the

00:19:26

1st year of spermatogenesis we get 4

00:19:30

sperm from one sperm

00:19:33

4 sperm from 1 and in the car I get one

00:19:37

egg and 3 guide bodies and

00:19:41

everything is also spelled out here: the sperm of that person does not

00:19:43

begin to actively divide at

00:19:47

puberty and this process goes on continuously,

00:19:50

that is, the process of spermatogenesis in

00:19:53

boys begins at

00:19:55

puberty, before that nothing happens in them,

00:19:59

but in girls they are laid

00:20:02

at the stage of the embryonic period, that is,

00:20:06

when the girl was still in

00:20:09

her mother’s tummy, in her womb, she was already

00:20:15

laid in the car for loss, and then when the girl

00:20:20

enters puberty, from

00:20:23

that moment on, every month,

00:20:26

one egg begins to mature, only

00:20:28

one per month, but in the car, everything is already

00:20:31

laid, so there is such a joke that the

00:20:35

grandchildren

00:20:37

were already in the grandmother’s belly, that is, they

00:20:41

were already in the grandmother’s body because

00:20:44

the pedal is not a joke, it’s true because

00:20:46

the grandmother is a daughter in her and the daughters are already about the

00:20:49

car which in the future will turn into a

00:20:53

child

00:20:54

into a grandson,

00:20:57

yes, in men the process of spermatogenesis with

00:21:02

without if there were no pathologies, it

00:21:04

occurs until death, as

00:21:08

the teacher said, until

00:21:09

the last breath,

00:21:10

and in women, the maturation of eggs

00:21:13

occurs before menopause, which usually

00:21:16

occurs

00:21:17

from 45 to 55 years, somewhere at this

00:21:21

age, the formation of

00:21:24

eggs ends and,

00:21:26

accordingly, the childbearing

00:21:28

period ends for a woman,

00:21:34

so what

00:21:37

if the girl is infertile, well then the

00:21:40

grandson will not be destined to be a tradition of

00:21:45

grandchildren, as it were, they were conceived but were not born,

00:21:48

so to speak

00:21:50

further, we will analyze this point in the

00:21:54

process of spermatogenesis, 4

00:21:57

gametes are formed from 1 and in the carriage the axis and simplification of

00:22:01

sperm are not

00:22:06

in the process about the vagina, only

00:22:09

one gamete is formed from one about the carriage and

00:22:17

for the vagina for a very important

00:22:19

remarkable thing, the final

00:22:21

process of genesis is completed only

00:22:24

after fertilization, this

00:22:27

is typical for vertebrates, that is, first from the second

00:22:30

order, then fertilization, only for the

00:22:32

same reason we can call it

00:22:34

complete egg, although sometimes this is

00:22:37

neglected and they say that

00:22:40

ovulation has occurred, the egg has entered the

00:22:42

fallopian tube, although it has not yet been

00:22:44

fertilized, and there are such and such

00:22:47

inaccuracies in this matter, but

00:22:50

spermatogenesis and everything is simply formed by a

00:22:52

second-order spermatocele from sperm

00:22:55

to sperm and that’s all and only then

00:22:58

fertilization

00:23:01

why infertility is formed oh even you

00:23:05

of course raised such a pressing topic for a

00:23:07

huge number of reasons it could

00:23:10

be the absence of ovulation

00:23:12

it could be due to the fact that for example a

00:23:14

woman was exposed to radiation and all

00:23:17

her eggs turned out to be ineffective

00:23:20

they all died or picked up mutations

00:23:24

due to radiation these all of her in the carriage,

00:23:27

accordingly, there

00:23:30

will be no more healthy eggs

00:23:32

then there

00:23:34

may be something with the uterus, that is, everything is

00:23:38

fine, she ovulates but the uterus is not

00:23:40

capable of receiving, that is, the

00:23:44

embryo does not implant into the uterus,

00:23:47

this may be the reason for a man 50

00:23:50

percent of problems with the flesh related to

00:23:52

mobility,

00:23:54

more on the male side, it could be a

00:23:57

violation of sperm motility, a

00:23:59

violation of the activity of

00:24:01

sperm enzymes, and so on,

00:24:05

about ectopic pregnancy Ksyusha, I

00:24:08

will show you because I have

00:24:10

a picture for that, let’s

00:24:13

do this task, establish the

00:24:15

sequence of stages about vaginismus she

00:24:18

without a catch, it seems that everything here is usually

00:24:21

try it yourself,

00:24:23

so let’s see that there is the formation of

00:24:27

first-order compartments, the formation of qi

00:24:29

cells, mitotic division, the horse of me

00:24:33

your associate of fathers thoats and you, but

00:24:36

first of all, let’s choose curtains,

00:24:41

choose fire and methodical division in the

00:24:45

fire f

00:24:47

thirds long ago write immediately give a complete answer

00:24:50

not to the first point directly give a

00:24:52

complete answer, then it will be

00:24:54

unclear who

00:24:57

who belongs where what

00:25:00

so methodical division fire and they

00:25:03

divided

00:25:04

then oocytes of the first order are formed

00:25:11

oocytes and the first order grow the growth of

00:25:14

oocytes and accumulation of nutrients

00:25:18

then the

00:25:22

fathers of the first order must enter

00:25:25

in mitosis and meiosis, acetate of the first order

00:25:29

results in the formation of flowers of the second

00:25:31

order and

00:25:33

this leads to the formation of eggs and

00:25:36

polar bodies

00:25:40

315 462 yes, good, you lox are super,

00:25:47

now let's look at the structure of the gametes,

00:25:51

what we got by finishing off is missing a little,

00:25:54

no big deal,

00:25:56

sperm we get sperm

00:25:58

with tails what they are made of

00:26:00

the sperm secretes the head the middle

00:26:03

part or neck it can be the neck and

00:26:06

the tail from the

00:26:08

head there is the nucleus itself the most valuable thing

00:26:12

that needs to be brought into the egg there

00:26:15

is genetic information from the

00:26:17

father

00:26:19

half of the set of chromosomes the child will have

00:26:22

from the father and that’s exactly what it is located

00:26:25

now there is a haploid set,

00:26:26

then in the head there is also an ohm color, and the

00:26:31

beauty contains a bunch of enzymes that

00:26:34

will help break down the shell of the egg and

00:26:37

penetrate inside without color and

00:26:40

the sperm will suit the cassie cells and everything

00:26:42

will not be able to pass into it because it is

00:26:45

well protected from 1 ohm is a

00:26:48

derivative complex racer why

00:26:51

namely the golgi complex remember

00:26:53

what function the golgi complex performs

00:26:58

what is the function of the complexes more

00:27:02

ayman tina just not the lysosomes but the

00:27:05

complex howling on the complex the complex is

00:27:08

more capable of forming just

00:27:10

lysosomes are produced you write correctly

00:27:13

and

00:27:14

the bolt contains a large number of

00:27:16

enzymes because the golgi complex it

00:27:18

converts proteins into enzymes and

00:27:22

packages them in lysosomes and,

00:27:24

accordingly, these enzymes are actively formed by color;

00:27:29

in the neck there is a large number of

00:27:32

mitochondria, that is, all the mitochondria

00:27:34

that were in the cells move here,

00:27:37

here they are not and the tail of the tail is

00:27:42

necessary; due to its contractions,

00:27:45

the sperm moves, there are

00:27:48

a lot of mitochondria here are needed

00:27:52

in order to release energy

00:27:54

for the contraction of the tail in order to

00:27:58

carry out its motor activity,

00:28:00

so we looked, now let’s look

00:28:03

at the egg, here

00:28:05

it is, the egg does not secrete a whole

00:28:08

bunch of shells, which, in general, for

00:28:11

wigwams you don’t need to know, but for general

00:28:13

development we have listed it here which

00:28:16

contains the nucleus and in the game there will be

00:28:18

another half of the genetic

00:28:20

information

00:28:21

that the child will get from the mother, there

00:28:24

are islands of plasma, both plasma is like

00:28:27

cytoplasm, only the cytoplasm of the egg

00:28:29

and the veins are the

00:28:31

exact shell with a supply of

00:28:33

nutrients quite

00:28:35

impressive, the transparent shell, the

00:28:38

corona radiata and all these the

00:28:41

sperm will have to

00:28:45

overcome the membranes in order to overcome them, he

00:28:47

uses the enzymes that were

00:28:50

in his colors, these enzymes begin

00:28:53

to break down this membrane, in fact, at

00:28:56

this moment a huge number of

00:28:58

sperm

00:29:00

are working to break down this membrane,

00:29:03

and indeed, to break down this

00:29:05

membrane, a large number of sperm are required,

00:29:06

but only one penetrates

00:29:12

only one penetrates inside and at the moment of

00:29:15

penetration

00:29:16

it throws off its neck and tail, it

00:29:19

all falls off and only

00:29:21

the head with the nucleus penetrates and

00:29:23

now there is such a nuance where all the

00:29:26

mitochondria remain, all the mitochondria of the father where

00:29:30

they will remain

00:29:36

so

00:29:39

where do you think the mitochondria went after

00:29:43

all, the mitochondria are for you

00:29:45

there is also genetic information in the mitochondria, there

00:29:47

is ring DNA with

00:29:50

genes that encode

00:29:53

mitochondrial enzymes and the

00:29:55

sperm are left

00:29:57

outside and in the end all the mitochondria

00:30:01

that go to the child they go to

00:30:04

him are maternal, so our DNA of our

00:30:09

mitochondria is all maternal and therefore

00:30:13

mitochondrial diseases are transmitted

00:30:15

only from a woman, so at our

00:30:17

university we had a lecture

00:30:21

on biochemistry which was called

00:30:23

mitochondrial diseases and the teacher

00:30:26

wrote in parentheses or again

00:30:28

women are to blame for everything,

00:30:30

so in general all our mitochondria

00:30:33

only come to us from a woman

00:30:35

because the sperm and while

00:30:38

their mitochondria penetrated the egg we lost everything

00:30:41

and that’s how fertilization happened,

00:30:45

this is my old photo of you guys,

00:30:49

you also had this, but

00:30:52

now, probably, no one

00:30:54

took a photo

00:30:58

about the corona radiata about

00:31:01

the corona radiata, this is one of the membranes

00:31:04

that the sperm needs to overcome

00:31:06

and guys, the sperm

00:31:08

always penetrates alone even if the

00:31:10

result is twins and still only

00:31:12

one sperm, how

00:31:14

twins are obtained later I’ll tell you,

00:31:16

so only one sperm

00:31:19

will penetrate even when twins are what

00:31:24

can cause twins to occur right away, I’ll

00:31:26

tell you there are two eggs, you know this, you are

00:31:29

twins, fraternal

00:31:37

fraternal twins occurs

00:31:40

if it so happened that a woman

00:31:42

accidentally ovulated two eggs at once,

00:31:44

that is, initially there are two

00:31:47

eggs, this event is very rare, but

00:31:50

this can happen and,

00:31:52

accordingly, one egg

00:31:53

is fertilized by one sperm,

00:31:56

2 eggs are fertilized by another

00:31:59

sperm, we will get 2

00:32:04

different yawns,

00:32:06

this one will have a set of thomson tm strokes and this one

00:32:10

just 2 and 3 genetic information

00:32:13

they will have completely different from different

00:32:14

eggs and from different sperm

00:32:16

they will be as different as

00:32:19

children

00:32:21

born in two different pregnancies can be different and

00:32:25

there are identical twins

00:32:31

when there was one egg it was

00:32:35

fertilized by only one

00:32:37

sperm and

00:32:40

everything turned out it seems to be normal and a

00:32:42

zygote, but then something goes wrong and it

00:32:44

doubles and

00:32:46

bifurcates, you get 2 zygotes, but

00:32:49

since they had the same set

00:32:52

of chromosomes, everything was the same because

00:32:54

from one cell these are from one

00:32:55

sperm, these are identical twins

00:32:58

genetically identical and they are born to

00:33:02

them they will be genetically identical if

00:33:05

one grows up to be fat and the other one is thin,

00:33:09

it’s not because this one has

00:33:12

no predisposition to be overweight,

00:33:15

they are genetically identical and it’s just that one

00:33:17

ate more or he got more food

00:33:20

and 2 were fed little, that’s why one became

00:33:23

fat, the second remained thin, but

00:33:27

these two may have different genetic

00:33:29

information, 1 may have a genetic

00:33:31

predisposition to obesity, the other does

00:33:33

not, they are fraternal twins, in general,

00:33:35

this is the story, and now where

00:33:40

does the fertilization process take place, which means the

00:33:42

brass egg is formed in the ovary at

00:33:46

the time of ovulation in a girl, it comes

00:33:49

out here in an hour there were such in the carriage and

00:33:52

they ripened ripened ripened,

00:33:55

such a follicle appears, it grows,

00:33:59

grows, grows every month and at one

00:34:01

moment bursts and the egg comes out into the

00:34:05

fallopian tube, so it gets into the

00:34:07

fallopian tube, but in 3 then the uterus ovary

00:34:11

uterine tube the ovary is connected to the uterus of the

00:34:14

fallopian tube, meanwhile, if the

00:34:20

sperm enters the uterus, they

00:34:23

enter the fallopian tube and

00:34:25

fertilize the egg;

00:34:27

fertilization occurs in the

00:34:29

fallopian tube; if it is all

00:34:32

fertilized, then this zygote

00:34:39

begins to descend

00:34:41

through the fallopian tube into the uterine cavity;

00:34:45

at this time, growth in the uterus increases the endometrium is

00:34:48

such a thick layer of ideal tissue, it is

00:34:52

so lush and allows the

00:34:55

zygote to easily immerse itself, it

00:34:59

immerses itself in it, and at this moment

00:35:01

we say that pregnancy has arrived,

00:35:03

then this zygote begins to

00:35:06

grow into the uterus,

00:35:09

but it is no longer a zygote

00:35:11

it will be a small embryo and is already beginning

00:35:14

to grow and divide and turn into the

00:35:16

future child of a

00:35:21

neighbor for identical paladins, for different

00:35:25

think the gender may also be different,

00:35:27

so another option is if

00:35:31

ovulation occurred, the egg came out into the fallopian

00:35:34

tube

00:35:35

and the sperm did not come, well, there was no

00:35:38

sexual intercourse there, for example what then this

00:35:42

egg comes down here, this

00:35:45

endometrium, people are all upset that we

00:35:48

came here and no one was waiting for us, and

00:35:51

this endometrium begins to come out,

00:35:55

the egg exfoliates, too, and all this comes out in

00:35:58

the form of bloody discharge, which

00:36:01

is called menstruation

00:36:03

before and this happens every month

00:36:06

after some about a

00:36:09

week and a half after ovulation,

00:36:11

she was still hoping for a few days

00:36:14

before the sperm had given, and if not, then no,

00:36:16

it begins to exfoliate,

00:36:17

so about an ectopic pregnancy,

00:36:21

ask in what case this happens

00:36:23

if, after all, the sperm fertilized

00:36:25

the egg, and for example, the woman had

00:36:28

frequent inflammatory processes, what -

00:36:31

and then the fallopian tube narrowed due to inflammatory

00:36:34

processes, well, there

00:36:35

were some kind of growths or something else or some kind of

00:36:38

mucus was too thick here and

00:36:41

this embryo got stuck here and that’s it, and then

00:36:46

this enlargement begins, you

00:36:48

have to do an operation removal of the

00:36:50

fallopian tube to remove this

00:36:53

embryo, that is, this situation is unpleasant,

00:36:55

to save such a pregnancy, as far as I

00:36:57

know, it is impossible how a miscarriage occurs,

00:37:01

a miscarriage may also have different reasons,

00:37:04

one of the implantation is disrupted, in the

00:37:07

early stages, before I tried, for example,

00:37:09

to implant, but something went wrong and

00:37:12

everything goes higher

00:37:14

there is a long story about miscarriages and what

00:37:18

boys boys will listen to is

00:37:20

firstly boys we have the majority of

00:37:22

future doctors here secondly they will have a

00:37:25

wife and daughter you still need to understand how

00:37:28

all this happens

00:37:31

if the fallopian tube is removed

00:37:34

a woman will be able to get pregnant because

00:37:36

she has there is one more fallopian tube 1 month

00:37:39

this ovary ovulates for the second month this

00:37:41

ovary and for a month when

00:37:44

this ovary will ovulate we can

00:37:46

get pregnant on this side we can’t

00:37:48

get pregnant anymore here is a

00:37:57

separate webinar on the opposite to come out

00:37:59

even then the funder everyone let’s now at

00:38:03

least one of course yes it’s useful, it’s

00:38:05

interesting, but there’s also a

00:38:08

long story about miscarriages, let’s look at

00:38:10

this task in the twenty-seventh task,

00:38:13

which could also be, but

00:38:16

lately they haven’t been introducing

00:38:18

gametogenesis 27, well, we have to be

00:38:21

ready for anything, the somatic cells of the

00:38:23

Drosophila fly are contained in 8 chromosomes,

00:38:27

determine the number of chromosomes and DNA molecules

00:38:30

in cells during spermatogenesis in the

00:38:34

reproduction zone and at the end of the maturation zone of

00:38:37

gametes

00:38:39

Karina asks how to find out which month is

00:38:42

which ovary, but this can be seen on an ultrasound,

00:38:45

firstly, and secondly, some women

00:38:48

feel directly on which side they feel

00:38:50

when they have ovulation occurs, not

00:38:53

everyone can clearly say this,

00:38:56

I have this ovary today Fowler's shaft

00:39:11

somatic somatic these are not sexual

00:39:16

they are sexual it is always when they

00:39:20

give it to you they mean 22 c that is, the

00:39:22

original in the original

00:39:24

somatic cell was a set of us sun two and two

00:39:27

prices, which is equal to 8 chromosomes, 8 DNA molecules,

00:39:34

this is somatic and since this always

00:39:37

needs to be remembered, determine the number of

00:39:39

chromosomes and DNA molecules in the

00:39:42

reproduction zone and at the end of the maturation zone, the reproduction

00:39:53

zone, the reproduction zone, we have about the carriage and

00:39:59

and the carriage usually has a set of chromosomes 2 m

00:40:03

20 this 8 chromosomes and 8 DNA molecules I really do

00:40:08

n’t like this task because they

00:40:10

don’t specify

00:40:12

exactly what period before replication and

00:40:15

after replication in the answer that they

00:40:17

indicate in the reproduction zone 88 before, that

00:40:20

is, here they usually did

00:40:23

not indicate anything, but they think that everything is

00:40:27

simple into the fire it is 22 c and at the end of the

00:40:30

gamete maturation zone at the end of the maturation zone

00:40:33

when the entire mejos

00:40:42

set of chromosomes has already occurred there will be n.s. this is only

00:40:46

half as much

00:40:47

28 divided by 2 will be 4 chromosome and 8 dna is

00:40:53

half as much as 4 dna

00:40:57

answer justify what processes

00:41:00

occur in these zones the

00:41:02

reproduction zone somatic cells are

00:41:05

divided by mitosis therefore the

00:41:08

same somatic cells are formed or a set of monsoons is the

00:41:11

same as the somatic

00:41:12

zone maturation goes mejos I will learn here

00:41:16

I wrote that ago the sperm of that

00:41:19

one is formed and the

00:41:25

maturation zone goes mejos therefore at the

00:41:28

end of meiosis haploid

00:41:30

cells are formed as reduction

00:41:33

division occurs until

00:41:35

the next one, this task is to determine the

00:41:37

number of chromosomes and the number of DNA molecules in the

00:41:40

chicken car before division begins here

00:41:46

we will need the information that you and I

00:41:48

wrote that a carriage has a set of

00:41:50

chromosomes two n 20, but if you are asked

00:41:54

right before division, it means that

00:41:56

replication has already occurred and they we will

00:41:59

assume that they come on at 4 s, this is the

00:42:01

case when the carriage and will already have

00:42:05

a set chromosomes and DNA 424 prices and in the

00:42:10

first-order compartment and the first-order chain

00:42:12

has a set of chromosomes 2n 4c

00:42:17

let's see how they wrote the answer the number

00:42:20

of chromosomes in the carriage before division 2-4 prices

00:42:24

this is observed because fire and deepoy are

00:42:27

not but the number of DNA molecules before division

00:42:30

doubles if they didn’t write to you

00:42:33

before division, then you would write 2 of this

00:42:36

price

00:42:37

the number of chromosomes in the first-order compartment is

00:42:40

24 c this is observed because the

00:42:43

first-order oocyte is formed from a dipole

00:42:45

and fire I as a result of me who for and the number of

00:42:49

DNA molecules before division was doubled like

00:42:53

this quite simply very similar

00:42:58

to the topic of mitosis and meiosis, well, let’s

00:43:02

look again at fertilization, how it

00:43:04

happens, here it is, an egg, an egg

00:43:07

consists of various egg membranes, a

00:43:11

cytoplasmic membrane and cytoplasm, which is

00:43:14

also its plaza, here it is a sperm with a

00:43:17

head, a neck and a tail, the

00:43:19

head has a color and contains

00:43:23

enzymes enzymes break down the

00:43:25

shells of the egg and sperm

00:43:28

china it will penetrate into the personal

00:43:31

space of the egg

00:43:34

Nastya will be here the

00:43:37

sperm penetrates there and

00:43:40

throws off its tail along with the neck and

00:43:43

together with its mid-hunts and then the

00:43:47

nucleus of the egg and the nucleus of

00:43:49

the sperm begin to merge with each

00:43:53

other and

00:43:54

if each was haploid, then after the

00:43:57

merger we get that we get a yawn

00:44:01

with a diploid set of chromosomes,

00:44:03

what happened to them next and then

00:44:09

embryogenesis will begin,

00:44:12

fertilization has occurred, we have turned out and

00:44:15

a year,

00:44:16

let’s first introduce such concepts

00:44:19

to you as ontogenesis and embryogenesis

00:44:23

ontogenesis is the individual development of the

00:44:26

organism from the formation of the zygote

00:44:31

until death,

00:44:35

the grave is like this

00:44:37

and

00:44:38

until death,

00:44:45

ontogenesis is and this is the history, let’s say, of the

00:44:48

entire life of a particular organism of mine,

00:44:51

yours, and so on, but

00:44:53

this is all ontogenesis,

00:45:01

embryogenesis is the individual development of the

00:45:04

organism from yawning to birth, this is

00:45:11

embryogenesis, that is, embryogenesis

00:45:15

is part 1 before the first stage of ontogenesis,

00:45:27

well, I see that if I see that there

00:45:30

was some question about it, you already noted

00:45:32

that everything is

00:45:33

so good,

00:45:37

now

00:45:39

we will talk to you today about

00:45:42

embryogenesis in great detail, and so its

00:45:45

egg then begins

00:45:48

to split up, but it’s necessary now from

00:45:50

a single-celled state it will turn into a

00:45:52

multicellular no, no, we were then

00:45:55

all our lives in this zygote, we consist of

00:45:57

many cells, how did this happen,

00:45:59

the zygote begins to divide, first it

00:46:01

divided once, then the second time one

00:46:05

of them divided, it turned out to be two cells, but

00:46:07

here this technique is unusual, this is how it

00:46:10

divides all mitosis but there is no

00:46:14

increase in the number of

00:46:17

cells increasing in size court this

00:46:22

cell divided but the cells do not grow

00:46:24

then divided again already four

00:46:26

cells turned out there again dad and

00:46:29

divided already 8 cells again 16

00:46:32

cells we still get a morula and 16

00:46:35

cells and the morula is the same size the

00:46:39

same as the zygote since the cells did not grow in the

00:46:41

interphase, such a peculiarity is

00:46:45

that in

00:46:47

this process of crushing it, you between the

00:46:52

methods of the interphase contained only during the

00:46:55

period there was replication, but

00:46:58

this accumulation of

00:47:00

nutrients and all this did not occur, the

00:47:03

throat inside is

00:47:05

all filled, but then a

00:47:09

cavity appears in this module and when

00:47:12

such an empty space appears there,

00:47:14

this already causes a blastula,

00:47:16

so the first stage is called

00:47:20

fragmentation between divisions,

00:47:23

there is a short interphase consisting

00:47:25

only of a period, so the total mass

00:47:28

does not change, it is divided once again

00:47:31

and again it turns out to be a morula, then an

00:47:35

empty space begins to appear in the module

00:47:37

and we get the same

00:47:39

bubble, this is a blastula, the first stage

00:47:42

of etching leads to the appearance of a blastula, a blastula

00:47:45

is a single-layer embryo, a

00:47:51

single-layer embryo,

00:47:57

this is the moment that I wrote to you,

00:48:00

be sure to remember the enemy of the catch was about

00:48:02

this question, he is right on this

00:48:08

I paid my attention, that is, there was a question, what is the

00:48:10

specific feature of the division in the image of the

00:48:13

transformation of the blastula,

00:48:15

what happened next with this bubble, it turned

00:48:18

out like this in the eye,

00:48:20

here is one layer of cells, you can

00:48:22

draw it like this,

00:48:31

you have a round and

00:48:34

then this bubble, this blastula

00:48:38

begins to protrude just

00:48:41

imagine if you have a ball, you

00:48:43

pierce the output and it begins to swell and

00:48:46

one side is absorbed like this 0

00:48:48

platform show here we see

00:48:53

a blastula and one wall ends

00:48:56

inward, it is pumped in and we already get a

00:49:00

two-layer embryo consisting of an

00:49:03

outer wall and an inner wall

00:49:07

which has a cavity was inside the blastula, it was

00:49:09

called the blastocoel,

00:49:13

then we had one wall moving back and

00:49:18

from a single-layer embryo the embryo

00:49:21

became a two-layer one, it has an outer

00:49:24

wall called ectoderm

00:49:28

and an inner wall called m, then the

00:49:32

dermis is also the endoderm, yellow

00:49:35

ectoderm, blue

00:49:37

and it will always be something internal

00:49:40

act outside what we have in this hectare

00:49:44

this stage is called gastrula in it we

00:49:47

highlight the

00:49:49

cavity that is inside but it

00:49:52

will no longer be called it was become it will be

00:49:55

called gastro goal or in another way it is

00:49:58

called the gastrula cavity from not eat

00:50:02

the primary intestinal will further develop a

00:50:04

cavity

00:50:06

in the future, but this is a hole

00:50:09

like this, a hole has formed here,

00:50:13

this is a blast, I wanted them to tour, but

00:50:18

we are all called by the blast chord, this is confusing, we have to come to

00:50:20

terms with it, the

00:50:23

mouth will develop from it, and now such a

00:50:26

moment if

00:50:29

from this there was astapor and the

00:50:32

mouth actually develops, there will be a mouth in the future, then this is the

00:50:35

primary genus and the

00:50:38

genus and animals, and if such a misunderstanding occurs from this

00:50:42

primary mouth

00:50:44

and an

00:50:47

anus is formed and the

00:50:52

genus begins to break through on the other

00:50:56

side, then we call such people a secondary genus,

00:51:00

but this is a secondary mouth and we are secondary mouth

00:51:04

and who belongs to whom we will talk at

00:51:07

the factory about this primary secondary mouth and

00:51:10

we will come back

00:51:12

yes

00:51:14

yes we got awkwardly where the

00:51:18

mouth should have been we went wrong

00:51:22

so gastrula means we got the condition of

00:51:25

the fire remembering what we had we had

00:51:27

yawning is already up to one cell, then we

00:51:31

had a morula, for some reason it constantly

00:51:34

ignores it, so we immediately write the eye tula

00:51:37

blastula, then a single-layer embryo, one

00:51:40

layer, and now we got the gastera

00:51:44

gastrula consists of two layers, which then the

00:51:47

gastera begins further and

00:51:49

it changes in all sorts of ways here

00:51:53

it happens firstly

00:51:55

from the ectoderm from the outer layer, here

00:51:59

cells begin to divide, a

00:52:01

neural plate appears, here it

00:52:04

is, the neural plate, then this is

00:52:07

the neural plate, here it begins

00:52:09

to bend and eventually turn

00:52:13

into an additional tube from this

00:52:15

neural plate, in the future the

00:52:17

neural plate will be formed tube, which

00:52:22

means the entire nervous system will develop from it, that’s

00:52:25

all that concerns the

00:52:27

nervous system, it could be the

00:52:30

brain, it could be the

00:52:35

spinal cord, the

00:52:39

spinal cord, nerves,

00:52:41

analyzers, receptors, and so on, but also

00:52:45

similar to what is obtained from what tissue is the

00:52:48

neural plate formed from a barrel from

00:52:51

what leaf from the act or and order of

00:52:55

nervous tissue is formed from the ectoderm and

00:52:59

therefore further we will say that the entire

00:53:01

nervous system is formed from the ectoderm,

00:53:09

well done, remember this moment, this is

00:53:11

already a hint for you when you teach

00:53:13

what is formed from which germ

00:53:15

layer, this will already help you well, that’s

00:53:18

all with the neural plate, we figured out

00:53:20

that then

00:53:24

some new cells begin to appear from the endoderm, new

00:53:27

cells that

00:53:30

will subsequently accumulate here and

00:53:34

another layer of mesoderm is obtained and a

00:53:38

notochord is formed from the mesoderm, and the

00:53:41

horde map also has a normal

00:53:44

origin from the notochord. develop

00:53:48

[music] the

00:53:49

axial skeleton of the bones and all the derivatives of the

00:53:52

bones, well, in the end we see that all this is

00:53:56

also from the mesoderm, called

00:53:59

the endoderm, it also curls up here into a

00:54:02

tube and

00:54:04

from this endoderm the intestines will develop there

00:54:05

and so on and some

00:54:08

internal organs, that is, the endoderm

00:54:10

will lining us practically from the inside,

00:54:13

the ectoderm covers us from the outside, plus the mesoderm

00:54:16

will form its own nervous

00:54:18

system from it, such an intermediate

00:54:20

layer,

00:54:21

look that the endoderm inside forms

00:54:25

such a cavity, this cavity will be the cavity of the

00:54:27

primary intestine or the primary cavity, and

00:54:31

here these are similar, this primary cavity

00:54:35

has already arisen, a landmine is truly here it is

00:54:37

only it has changed a little here,

00:54:39

so if they ask you where the

00:54:41

primary cavity was formed, you

00:54:43

say not in no roll, you say that

00:54:45

it was formed already on tour, so it was

00:54:48

already there, that it

00:54:51

changed there a little bit, but the secondary cavity is

00:54:54

formed here in the mesoderm and it

00:54:56

is formed as you see in the nerve they are

00:55:00

formed into nerves Nastya yes she now

00:55:03

we said it

00:55:05

then we got three germ

00:55:09

layers three main ones this is the

00:55:12

blue ectoderm this is this yellow

00:55:15

endoderm and mesoderm from the mesoderm we also

00:55:18

got a notochord and from the ectoderm

00:55:21

we got a neural plate which

00:55:24

then will turn into a neural tube, then

00:55:29

tissues will begin to develop from these germ layers, acquired the process of

00:55:32

tissue formation, call them histogenesis

00:55:35

because histology is the science of tissue

00:55:38

places with this tissue and the

00:55:42

science of

00:55:47

leaf tissue this tissue and well, diss to gain

00:55:50

with genesis something is formed places

00:55:53

of tissue, then some organs begin to appear from these tissues,

00:55:55

this process

00:55:58

is called organogenesis or the process of

00:56:00

organ formation, and then

00:56:03

various organs of the system appear which of which

00:56:06

germ layers you need to know, but you don’t

00:56:09

know by and in almost every

00:56:11

variant,

00:56:12

well, not in every via variant they give

00:56:15

this task to correlate the ectoderm

00:56:17

of the endoderm, for example, with the guitar and

00:56:21

such sects of the dermis are formed by the epidermis of the

00:56:25

skin,

00:56:28

that is, the ectoderm to cover on the outside

00:56:30

means this is the epidermis of the

00:56:33

skin derivatives of the skin so derivatives of the skin

00:56:35

include sweat glands sebaceous glands

00:56:38

mammary glands

00:56:40

hair nails enamel of teeth nervous system

00:56:44

because we saw that from the ectoderm the

00:56:46

neural plate is formed, the

00:56:49

sensory organs they develop from the nervous system,

00:56:51

and also the pituitary gland and pineal gland from below, so

00:56:55

remember the endoderm is what lines

00:56:59

us from the inside, this digestive system, this

00:57:01

includes the respiratory system, the

00:57:06

digestive glands, the liver, the

00:57:08

pancreas, the thyroid gland,

00:57:11

then the

00:57:14

mesoderm, the middle layer, something then the middle

00:57:17

between our outer layer between the skin the

00:57:20

inner layer of the digestive system

00:57:22

there will be muscles bones bones from the notochord

00:57:25

blood and lymph tissue

00:57:29

fluid is formed this is all liquid connective

00:57:31

tissue cartilage ligaments and tendons joints

00:57:35

genitourinary system

00:57:37

testes

00:57:38

ovaries but testes ovaries this is the reproductive

00:57:40

system it was possible not to write this

00:57:43

because we have already written the genitourinary system,

00:57:46

this is just to draw your attention to

00:57:48

ford escort and

00:57:51

many, many things will develop

00:57:53

adrenal glands and dermis, please note that

00:57:56

our skin consists of several layers:

00:57:58

epidermis dermis

00:58:01

and

00:58:08

subcutaneous fatty tissue

00:58:11

subcutaneous fatty tissue fat

00:58:14

epidermis

00:58:16

is formed from ectoderm

00:58:18

dermis adipose tissue is formed from mesoderm;

00:58:21

fat in general is

00:58:24

mesoderm; fat can also be included here; even

00:58:28

if the tissues are

00:58:30

ectoderm, this is mainly epithelial

00:58:34

tissue, very often and nervous; here is the

00:58:36

epidermis of the skin; this cave

00:58:39

gland is also epithelium; nervous tissue;

00:58:43

these are nerves; pituitary gland; and it is difficult to drink from here;

00:58:46

endoderm too basically epithelium

00:58:50

epithelial tissue is found here

00:58:52

mesoderm is either connective tissue

00:58:55

such as bones blood and lymph or

00:58:59

muscle tissue such as muscles for example

00:59:03

so well what is mesoderm formed from

00:59:06

mesoderm begins to develop from endoderm cells

00:59:11

endoderm cells

00:59:13

know this by heart at the test one hundred

00:59:17

percent next month you will be asked in as

00:59:20

a result, cells with the same

00:59:22

genotype

00:59:24

acquire different specializations during the formation of an organism, that

00:59:26

is, you really have a question: why do we

00:59:29

even have the endoderm here,

00:59:31

all the cells are the same, why the

00:59:35

respiratory system will develop from one cell

00:59:38

and the digestive system will develop from another cell, the

00:59:40

question is that there are

00:59:44

different specializations

00:59:47

acquires cells in the process of

00:59:49

differentiation and in the differentiation of

00:59:51

embryonic cells,

00:59:53

different genes

00:59:56

in the chromosomes are activated in different cells and therefore synthesizes

00:59:58

different proteins, that is, the original

01:00:00

cell was not yet specialized, it

01:00:04

can be called like this, like a patent for

01:00:10

the potency of

01:00:14

Tati, this is like everything is a patent for and

01:00:19

perhaps it can become the future of any

01:00:20

cell, they can call it a stem

01:00:23

cell,

01:00:26

then if it is influenced by some

01:00:29

differentiation factors,

01:00:34

differentiation factor number one town,

01:00:36

genes are activated that allows it to

01:00:39

become a cell of the respiratory system,

01:00:42

if it is influenced by other differentiation factors,

01:00:48

then other genes are activated and it

01:00:53

becomes, for example intestinal cell,

01:00:57

this is how it happens

01:01:00

under the influence of factors, it may

01:01:03

not necessarily be hormones, it may also be

01:01:05

hormones, but also other differentiation factors.

01:01:10

Now let’s talk about the structure of the embryo.

01:01:13

You don’t have this in your workbook

01:01:15

because I added it after a

01:01:17

new collection of round and here is a

01:01:20

drawing of his head, I have everything

01:01:22

after this picture, if you need it, I

01:01:25

can make a separate one, like a

01:01:28

checklist, you can print it out in yourself in

01:01:30

addition to

01:01:31

what is here, there is an embryo, here he is

01:01:35

with me, he really looks like an embryo, he has

01:01:38

no yolk the sac has an umbilical cord, there

01:01:41

is an allantois

01:01:45

on the outside, the embryo itself floats in such

01:01:48

amniotic fluid,

01:01:50

the amniotic fluid is enclosed in, and to me, a

01:01:54

romantic bubble is obtained

01:01:57

from the outside, and to me, it has such chorionic villi,

01:02:01

here they are, chorion villi, and here the

01:02:05

largest villi form the place where

01:02:08

the placenta is formed, let's Let's figure out

01:02:11

what is what and why it is needed

01:02:14

Chora

01:02:15

root is outside the embryonic membrane, that

01:02:18

is, it develops into the embryo from the

01:02:20

uterus,

01:02:22

which contributes to the nutrition of the embryo and

01:02:25

takes part in the formation of the placenta;

01:02:27

they form villi that contribute to

01:02:30

attachment to the uterus, that is, these villi

01:02:32

seem to grow into the uterus,

01:02:34

allantois outgrowth the intestines of the embryo, that is,

01:02:38

that is, it develops from the intestines of the embryo,

01:02:41

ensures gas exchange and accumulates

01:02:43

excretory products in mammals,

01:02:46

also participate in the formation of the placenta

01:02:48

and umbilical cord

01:02:50

placenta, who will be the placenta, I’ll show it to you,

01:02:53

this is an embryonic organ that

01:02:56

is formed from the chorion and alan girdle and

01:02:59

provides nutrition and gas exchange as well as the

01:03:03

removal of harmful metabolic products and

01:03:05

forms a game to attack the amber barrier,

01:03:08

look what it all looks like here is the

01:03:10

umbilical cord hell will be up to the embryo

01:03:13

very similar to the

01:03:16

embryo

01:03:17

this is the uterus

01:03:19

this wall of the uterus and the

01:03:22

umbilical cord it comes in the choir but

01:03:25

these are chorionic villi and not densely

01:03:28

braided and blood

01:03:30

capillaries, but this is the mother’s blood and, as

01:03:33

a result, from the mother’s blood

01:03:35

nutrients enter the blood, which

01:03:37

is in the choir then, and these

01:03:40

nutrients pass through the

01:03:41

umbilical cord and enter the embryo, the

01:03:44

embryo feeds on this, but there is

01:03:47

such a barrier and not everything some substances

01:03:50

get into the blood of the child, for

01:03:53

example, harmful drugs, not

01:03:56

everyone passes through this barrier, this

01:04:00

barrier is called Dima then

01:04:04

placental by

01:04:07

whom is this the placental barrier from the word

01:04:11

heme, this is blood and the placenta, the placenta and

01:04:15

blood do not mix, therefore the blood of the

01:04:17

mother and the child does not mix,

01:04:23

yes, and this is really when a

01:04:26

woman gives birth to a child, she pushes, the

01:04:29

uterus contracts, first

01:04:31

the baby comes out, and then the woman is told that

01:04:34

let’s

01:04:35

push some more and the placenta comes out, the

01:04:39

placenta is just like the placenta, with all

01:04:42

this goodness, she must also be given

01:04:44

birth, so to speak, otherwise she It

01:04:47

will remain there and begin to rot, and then

01:04:49

inflammatory processes will begin there,

01:04:50

all of this will have to be removed surgically, this is the

01:04:53

story, and

01:04:56

also the

01:04:59

amnion, the amnion, this is also outside the embryonic one

01:05:02

about the difference in the blood types of the mother and the

01:05:07

child

01:05:08

about where we have such a central

01:05:10

barrier if the mother has a negative

01:05:14

blood type in the child

01:05:16

positive

01:05:19

I would like to tell you better about

01:05:21

blood groups because here we often

01:05:23

talk about antigens, let’s

01:05:27

tell you the project later, there will be a

01:05:29

Rh conflict, but this can be avoided

01:05:32

a little later, the project I’ll tell you

01:05:37

Diana, it’s true that if after the birth of a

01:05:39

child a woman encapsulates her

01:05:42

placenta, there will be take then there

01:05:44

will be more energy some do this they

01:05:47

take this placenta and and somehow dry it

01:05:49

crush it put it to rest pack it in a capsule by a

01:05:52

woman then drink it but from a scientific point of

01:05:55

view there is no evidence

01:05:58

that it is effective or useful so I

01:06:03

believe that this is

01:06:05

my opinion that it’s ineffective,

01:06:13

some people even fry it and eat it, but the background is

01:06:16

normal meat, it’s environmentally friendly,

01:06:18

why not eat it,

01:06:21

but the benefit will be no more than

01:06:24

good chicken or beef meat, it

01:06:27

even smells a little bit of cannibalism, but that

01:06:30

means to me

01:06:32

[music]

01:06:37

outside the embryonic membrane is filled with

01:06:40

amniotic fluid

01:06:42

it Firstly, it provides mechanical

01:06:44

protection for the embryo; it is water there and,

01:06:47

accordingly, even if something

01:06:49

presses on the woman’s stomach, it will not be

01:06:51

damaged there so much because it is in this

01:06:52

water

01:06:53

during childbirth, this amniotic sac

01:06:56

bursts and the amniotic fluid

01:06:58

comes out, you may have heard the

01:07:00

concept that the water is leaving and it is

01:07:03

just pouring out, this is the amniotic

01:07:05

fluid, this is an important sign

01:07:08

for reptiles, birds and mammals

01:07:10

and reptiles, not everyone is there with

01:07:14

reptiles, the question is the

01:07:16

yolk sac,

01:07:19

the yolk sac is used like in

01:07:22

mammals as a hematopoietic organ, but

01:07:25

basically its main function is the supply of

01:07:28

nutrients substances,

01:07:37

well, let’s see what it all looks like

01:07:40

if I see in the picture and in the photo

01:07:42

the structure of the cat’s uterus with an embryo during

01:07:45

pregnancy,

01:07:47

so there is this, as you understand

01:07:50

during childbirth, the embryo is in

01:07:54

you, it’s not there, but there’s such a film outside

01:07:57

and inside there is liquid

01:07:59

according to number 3, the allantois is depicted from a

01:08:02

small area that

01:08:04

passes into the placenta according to number 6, the placenta

01:08:09

according to number 4 is the yolk sac,

01:08:12

in which, in addition to the

01:08:15

embryo, nutrients are also stored

01:08:19

according to number 5, this is a pathological

01:08:21

formation of a hematoma, as if from

01:08:23

dried blood, and

01:08:25

well, yes everything in general, everything is clear, clear

01:08:30

on the window, no luck, maybe

01:08:34

not the future, since he was photographed, who knows,

01:08:37

maybe he won’t be born fat anymore, well,

01:08:39

now let’s sum up what

01:08:41

happens in embryogenesis,

01:08:45

embryogenesis, in short, if without

01:08:48

details, then everything happens like that - then

01:08:52

then the blastula, then you can say first

01:08:55

the morula then the blastula, but the morula

01:08:57

is ignored in all tests; the blastula, the

01:09:01

blastula, occurs due to fragmentation,

01:09:07

then the gastrula,

01:09:11

then not the eagle, why is nervous called

01:09:15

nervous, why do you think the

01:09:17

nerve is the house of histogenesis, when

01:09:21

tissues and organs are formed, the

01:09:24

Guinness organ is no longer takes out

01:09:29

organogenesis, that's why there

01:09:34

is no nerve sophia hematoma and not everyone has it for some reason,

01:09:37

this cat got a

01:09:39

hematoma, apparently there was some kind of

01:09:40

bleeding, we also have a

01:09:42

hematoma anthem when we have such a canopy, you

01:09:45

know, with a lump there is a lot of dried blood,

01:09:47

this is also a hematoma when we have such a

01:09:50

bump in the hallway there, which means a hematoma, it’s

01:09:53

called

01:09:56

Daniel’s hematoma because the

01:09:58

neural plate begins to form there and the

01:10:00

rudiments of nervous tissue occur, the

01:10:02

nervous system appears, that’s why the

01:10:05

nerve is called

01:10:06

blastula, what kind of embryo is it single-layered,

01:10:10

double-layered or 3 layers

01:10:13

dominated by a single-layered embryo Gaspra

01:10:16

consists of two layers then there are acts of

01:10:18

the endoderm, and in it there is also a role in the

01:10:21

meat, a hole, a third layer, like this, in

01:10:26

general, follow along, don’t forget

01:10:28

that fragmentation is carried out by

01:10:30

mitosis, but between each division there is

01:10:33

no such full-fledged interphase,

01:10:36

yes, let’s now make this

01:10:39

stock exchange building that you they couldn’t stand it anymore, they wrote

01:10:41

the answer further with Sergey, they’ve already tied everything up

01:10:45

enough to endure, where do we start so here there

01:10:49

is

01:10:50

the formation of

01:10:52

meres,

01:10:54

you first have crushing and during

01:10:58

crushing you get blastomeres, these are

01:11:01

separate little things, right now I’ll show you what

01:11:03

exactly blastomeres are,

01:11:05

these little things are already blastomeres and

01:11:10

first blu-100 appears in measure only

01:11:12

then they are already formed into blastulas,

01:11:17

so this means the formation of blastomeres,

01:11:21

then

01:11:24

the formation of single-layer embryos or

01:11:26

blastulas, then the formation of

01:11:30

endoderm acts, this is the gastrula, then

01:11:33

the mesoderm appears in the neuron and already the

01:11:37

differentiation of tissues and organs, when

01:11:40

there are simple identical cells, we

01:11:42

begin to appear separately some

01:11:44

different fabrics that

01:11:46

differ from each other are

01:11:47

differentiated such and here four

01:11:51

315

01:11:53

24 well done, super well

01:11:58

if you didn’t do this then you weren’t

01:12:00

a child what is the last picture for you

01:12:05

well on this in general then the whole lesson was very

01:12:10

cool interesting and now guys in

01:12:15

general then we we are moving to a new stage,

01:12:16

very significant, we will move on to

01:12:18

genetics,

01:12:20

this is also just not that this is a special

01:12:24

life there, so to speak,

01:12:26

what on Monday we meet in

01:12:30

genetics on Tuesday, we will also

01:12:32

solve the task on protein biosynthesis for the

01:12:35

first part, if you need a

01:12:37

second part later on some

01:12:39

other Tuesday I’ll decide

01:12:42

for today it turned out to be a very fun

01:12:45

webinar about

01:12:46

everyone good luck in the tests Nastya about what

01:12:50

question

01:12:52

what question

01:12:55

please write again

01:13:01

when there will be evolution after genetics that

01:13:05

is, December is already December and January

01:13:09

if only one ovary

01:13:12

will also have menstruation but that is,

01:13:15

ovulation occurs, even

01:13:17

the egg is released and

01:13:19

then, accordingly, it cannot

01:13:23

be fertilized in any way since the sperm

01:13:25

will not be able to reach it because

01:13:27

there is no fallopian tube and the endometrium just begins

01:13:30

to peel off and a

01:13:32

period occurs, they will still be every

01:13:34

month but through meiosis 1 1 cycle

01:13:40

the woman will not be able to be fertilized because

01:13:42

the egg will not come out into the fallopian

01:13:44

tube that it is not there and in the second month

01:13:47

the egg comes out of the fallopian tube of everyday life and

01:13:51

on the other hand because there is a

01:13:53

fallopian tube and it can be

01:13:55

fertilized

01:13:56

task and about the chicken now

01:14:02

so

01:14:04

how many blocks are there Magomed in terms of

01:14:08

quantity, you need to calculate the exact figure, but I wo

01:14:12

n’t tell you, we still have genetics

01:14:14

and evolution,

01:14:15

anatomy and ecology, and everything

01:14:20

why there are no periods after childbirth, it

01:14:23

takes some time for the

01:14:26

hormonal levels to adjust, the woman immediately after

01:14:28

giving birth to the first carp, she just had a

01:14:31

huge surge there oxytocin increased

01:14:34

amount of progesterone during

01:14:36

feeding because of this, she does

01:14:38

not ovulate for some time until the hormones come to normal

01:14:41

and only then does ovulation begin after some

01:14:45

time,

01:14:46

usually this happens about

01:14:49

a year later, but for some it can be

01:14:51

much later

01:14:53

so about the chicken now guys, where is

01:14:56

this question

01:15:04

in the chicken carriage here they write to you

01:15:12

so determine the number of chromosomes and the number of

01:15:16

DNA molecules in the chicken carriage before

01:15:19

divisions begin, you and I know that there was a

01:15:23

primary sex cell with a set of

01:15:26

chromosomes in 14 c when the carriage is formed

01:15:29

they are formed by mitosis

01:15:34

is formed in

01:15:39

another carriage, but it could be

01:15:41

sperm of this kind, it doesn’t matter,

01:15:44

they are formed with a set of chromosomes in n20,

01:15:48

but since this is the reproduction zone, they

01:15:50

divide many times and these too

01:15:53

must divide again, but before they

01:15:56

enter the next mitosis they need

01:15:58

increase the set of

01:16:00

number of DNA molecules,

01:16:02

replication will occur, the set of chromosomes will become 2n 4c and

01:16:06

only now they will be able to enter the

01:16:10

next mitosis and therefore a new car will be formed

01:16:15

again with a set of chromosomes dn 20, that is,

01:16:18

immediately right before the

01:16:20

methodical division itself, they have to

01:16:22

increase the number of DNA molecules,

01:16:24

replication occurs therefore since

01:16:27

I’ll say here that right before the start of division,

01:16:30

then 2 and 4 c, and if this is not indicated, then it’s

01:16:33

like they haven’t just formed and there has

01:16:36

n’t been replication yet then write to two

01:16:38

20 I

01:16:39

even understood this moment

01:16:42

after today’s webinar everyone wants to

01:16:45

become a mint gynecologist now I think

01:16:47

that I I also wanted old people to become an

01:16:48

obstetrician-gynecologist for some reason, my

01:16:51

favorite field, but I’m not at the Faculty of Medicine,

01:16:53

so no,

01:17:00

everything is

01:17:02

fine then until Monday

01:17:08

I’ll try everything further that no, you don’t want to

01:17:12

become a gynecologist or it’s not clear

01:17:17

where the test will take place, your mentor

01:17:20

will call you,

01:17:22

but south video like this if you go to

01:17:27

52, in my opinion, there are poses and pediatrics, it’s very

01:17:30

problematic to go to gynecology

01:17:32

after just before the form, but after 52 you can

01:17:36

be a neonatologist, that is, a woman just

01:17:38

gives birth, expresses and the baby is immediately

01:17:41

handed over to you and you evaluate him there

01:17:44

how healthy he is, everything Is

01:17:47

he normal and so on,

01:17:54

this is also interesting, but after the

01:17:57

medical faculty of neonatologists it won’t

01:17:59

work out, and once again we have

01:18:04

genetics waiting for us, there are a couple more small topics, and

01:18:07

after genetics, such as selection, I drink

01:18:09

technologies and research methods, then

01:18:12

evolution,

01:18:13

then zoology, then anatomy and ecology

01:18:20

that such a section

01:18:27

of neonatologists is difficult, they are

01:18:30

born so small, they need

01:18:32

the size of a cat, they are really the size of a

01:18:35

cat, three and a half kilograms are born,

01:18:42

to be honest, I also gave birth to my

01:18:45

son, and I watched a lot of videos with

01:18:48

childbirth, and in the video they seemed like children... then

01:18:51

they are big and then my

01:18:53

child is born small, they are really lovely, they are so

01:18:57

tiny, in general it is very difficult with them,

01:19:00

they don’t talk and will tell you what is

01:19:03

wrong with them, but the pediatrician and neonatologists,

01:19:06

they are just mega people, they know a lot of

01:19:08

signals on how to understand what the child wants and

01:19:11

if there’s something wrong with him,

01:19:13

they can tell everything by reflex,

01:19:15

I just looked at them so oh my god

01:19:17

this is very cool bye

01:19:25

bye then if you have anything write and

01:19:29

ask questions

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