Proses Pembelahan Sel Secara Meiosis

Hi maybe you have ever thought why

I am different from my parents or

different from my siblings why my

parents' faces in their youth are not the same

as mine Even though I am their child Okay

you will know the answer in LED Science

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living things can grow and

develop because of the process of

cell division so why are we different

from our parents even though we come

from the same cell

This is because of meiosis division

meiosis division is also called

reduction division because it produces

offspring with half the number of chromosomes

of the parent chromosomes this is different from

mitosis division As explained

in the previous video

Hi meiosis division only occurs

in sex cells or former sperm and

egg cells located in the

male and female gonad glands in

meiosis division the number of chromosomes of the

parent and child cells is not the same because

there are two divisions namely

meiosis 1 and meiosis division

Hi even though meiosis and mitosis

look the same but there are some

fundamental differences in

mitosis division two daughter cells are produced

which are diploid or 2N while

meiosis division produces four

daughter cells which are haploid or n

as in mitosis division

meiosis looks the same meiosis division

also takes place after the interphase

or preparation stage where the

primary growth subphase occurs, the

synthesis subphase and secondary growth sofa set

in the DNA synthesis subphase

are replicated into two copies of each

chromosome so that they become two

identical chromatids in this subphase a pair of

centrioles also duplicate themselves and

begin to lengthen the kroto as well

Hai forming spindle threads

Hai identical chromatids bound to the

centromere will condense and shorten when

the division enters the prophase 1 stage

Hai until this stage

meiosis division is still the same process

as the mitosis division process but

there are two division stages that only exist

in meiosis division so that the results of

meiosis division contain genes with

high diversity first

occurs in the prophase 1 stage at

this stage the homologous chromatid pairs are

in parallel positions

Hai this process is called synapsis

this synopsis process forms tetrad pivalate

meaning Homologous chromosomes look the same

but actually contain game

Hai the second stage that differentiates from

mitosis division is crossing over

or crossing over at this stage

there is an exchange of genetic material between

non-identical chromatids

resulting in diverse game levels

tab Prophase 1 ends with

the melting of the nuclear membrane followed by the

movement of the centrioles towards the

opposite poles along with the movement of

these centrioles the spindle threads begin to

lengthen in metaphase 1 the centrioles are right at

the poles the spindle threads are

finished being stretched and the chromosomes are

bound by the spindle threads by the

kinetochore

Hi this stage shows the

basic differences between mitosis and meiosis division

in meiosis because of the

synopsis and crossing over process the chromosomes are

only bound to one spindle thread

on the kinetochore microtubules while

in mitosis division the two

identical chromatids are bound by spindle threads from

both poles

exhaust next in metaphase 1 the

chromosomes randomly line up on the

equator plane forming a

metaphase plate because they pair freely

this increases the possibility of

diversity

Hi in the anaphase 1 stage the chromosomes

then move towards the

opposite poles meiosis 1 ends with the

telophase 1 stage where the chromosomes begin to

lengthen and dare another Timur

appears and then the cytokinesis process

separates the two cytoplasms and

forms two daughter cells the final result

of meiosis 1 are two haploid cells

next is the stage of meiosis 2 in

meiosis 2 DNA replication no longer occurs

Hi centrioles duplicate themselves and

move towards the poles of each cell

in the prophase stage 2 chromatin pairs

shorten spindle threads are formed

and the nuclear membrane melts in metaphase 2

chromatid pairs are bound to

spindle threads and kinetochores

then are in a parallel position on the

equatorial plane and form a

metaphase plate i

Hi Then in the anaphase stage 2

chromatid pairs separate and the chromosomes

move towards their respective poles

Hi this is the final stage of the

entire meiosis division chromosomes

begin to lengthen and stop starting to

form again

Hi ISIS lottery interpretation occurs and

separates the cytoplasm into four

haploid daughter cells

Hi the haploid cells that are formed will be

specialized into gametes which

are sperm cells in men and

egg cells in women a child then

receives half the chromosomes from his mother

and half from his father because

men and women produce

millions of gamete cells and gamete selection at

the time of fertilization is random is the

main factor in the existence of various genes that are

formed this becomes reasons or

explain why we are not identical

or exactly the same as our parents

Hi So it can be concluded that there are several

factors that cause the first

is that in the prophase 1 stage there is

crossing over which causes various

games to form on the chromatids

Hi besides crossing over at the

metaphase 1 stage the chromosomes are randomly on the Equator

which will later become four

different gamete cells

Hi this process is called independent

assortment or free pairing

Hi the more chromosomes in

one organism the more

variations of gametes will be formed which is

as much as two to the power of n usually an

organism has three pairs of chromosomes

then the possibility of gametes being formed

is two to the power of three namely

Hi in humans there are 23 pairs of

chromosomes then the possibility of the number of

gametes is 2 ^ 23 what is

the value of course there are more than one

million gametes formed due to

crossing over or crossing over and

independent assortment or

free pairing this causes

gender diversity this is the reason why

we are not identical to our parents

or our siblings

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Hi thank you for watching hopefully

this video is useful for you hi hi