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Hello assalamualaikum warahmatullahi
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wabarakatuh previously congratulations to the younger
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siblings who have moved up to grade 9
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Hopefully more enthusiasm for learning, it's
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time for us to learn again at the beginning of
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this semester the first discussion is
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about the reproductive system in humans
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for the sub-topic of cell division,
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what is the material like, let's just go straight to it,
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don't forget to click like and
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subscribe, why can we be
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tall and grow big, then drink
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sports milk, okay, none of those answers are
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wrong, as living creatures,
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humans have the characteristics of growing and
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developing from babies to adults,
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growth and development are determined by
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the number and size of cells in our bodies.
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Hi, the more and larger the body cells
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will certainly make us grow
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taller so that the cells increase in number and
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size, the cells will divide. Well, that's what
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we will learn today, the purpose of
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cell division, including the first
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for growth, as explained
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previously, we can grow tall
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because cells divide continuously,
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eventually many and large, the second is
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repairing damaged bodies if
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our friends are injured, over time the wound will
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dry out and will close by
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itself, this is because the cells
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around the injured body part
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experience a cell regeneration process so that the
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cells divide and Finally a
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new layer of skin is formed the purpose of the
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third division is for
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reproduction reproduction or
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breeding is one of the characteristics of
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living things to be able to preserve
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their offspring then living things must
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produce little brothers and sisters know amoeba
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Hi single-celled or unicellular living things
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dividing themselves from one cell dividing
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into two daughter cells and so on Well
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because this video we focus on discussing
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the types of division in multicellular living things
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or living things that have
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many cells for example humans
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human cell division consists of two types namely
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mitosis and meiosis before studying
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What is mitosis and meiosis little brothers and sisters
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need to know first the
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parts of the cell that play a role in
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this division process is one cell
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each cell has a cell nucleus or
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nucleus the cell nucleus is covered by a
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thin membrane called the nuclear membrane
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inside the cell nucleus there are threads that
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carry hereditary traits called
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chromatin inside there are genes that
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determine the individual traits that come
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In addition around the cell nucleus there is a
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cell organelle called the centrosome
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this centrosome helps our cell division process
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starting from the division process by
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mitosis the place where this division occurs
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is in body cells or also called
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somatic cells the main purpose is for
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regeneration of damaged body cells the nature of the
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child cells in mitosis division is
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identical meaning the nature of the child cells is the same
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as the parent cell Why is that because
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after mitosis division does not
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change the number of chromosomes of the child cells
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usually the chromosomes of human body cells
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are symbolized by two n read as diploid
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46 human chromosomes or the same
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as 23 pairs in mitosis division
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is divided into four stages namely
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prophase metaphase anaphase and telophase
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abbreviated as pmab each has its
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own characteristics prophase at this stage the
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chromatin threads will thicken and
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shorten to form chromosomes and eventually
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will double to form chromatids the nuclear
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membrane will disappear the centrosome
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will divide into two centrioles and
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move to opposite poles in
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the middle of the two centrioles there will be
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fine threads called spindle threads
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metaphase stage at this stage the chromatids
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that have formed in the prophase stage
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will line up Straight in the division plane
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or straight in the middle like this the
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division plane is also called the equator plane
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anaphase stage anaphase stage is marked
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by the occurrence of chromatid division
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punya will go to the poles approaching the
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centrioles stage Telophase at this final stage
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is marked by the process of cytokinesis
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or division of the cell plasma which was previously
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one cell finally divides into two
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cells at the telophase stage also has
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characteristics that are the opposite of prophase if
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in prophase the chromatin thread thickens into
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chromosomes Well if the details of the phase are reversed
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then the chromosomes will return to being
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chromatin threads In addition, the nuclear membrane that was
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previously lost is now starting to
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form again and the centrioles that were previously
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two are now back to being one
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centrosome So between prophase and
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telophase are the opposite of each other one
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more type of division is meiosis
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this division occurs in sex cells
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or gamete cells the main purpose is to
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reduce chromosomes or reduce the number of
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chromosomes so that the chromosomes in the
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next generation always remain because there is a
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repetition of chromosomes
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then the nature of the child cells is not the same as the
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parent cell or the number of chromosomes of the
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child cells is half of the parent chromosomes
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if the parent cell chromosomes are 2m or diploid
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then the child chromosomes are m read as
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haploid because half of 2N yes still
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remember the total number of human chromosomes Yes
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exactly there are 46 pieces meaning
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as many as 2N or diploid = 46 pieces so
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for the child cells in division Meiosis is
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only half of it, namely 23
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stages that occur in the meiosis process,
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almost similar to the mitosis stage,
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only in the meiosis process it is divided into
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two, namely meiosis 1 and meiosis 2
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meiosis 1 consists of prophase 1
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metaphase 1 anaphase 1 and telophase 1 and
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meiosis 2 consists of prophase 2
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two and Veloz phase 2 or to
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make it easier from pkbts one continues
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to pqpqpq two each stage
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has the same characteristics as
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mitosis the difference is in prophase
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1 after the chromatin thread thickens
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tetrads or sister chromatids will be formed
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meaning the chromatids are double
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unlike in mitosis yes with
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adjacent chromatin will stick together so that
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this crossing over can make games
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exchange this is the main difference of
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meiosis So if it is described there is a different
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color on the chromatid arm for
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other characteristics it is the same as mitosis
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Hi in metaphase 1 the tetrads will line up
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in the plane equator anaphase 1 tetrad will
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separate and move to each
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pole telophase 1 cytokinesis
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or plasma division occurs into two
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daughter cells then continues to the
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meiosis 2 stage there is prophase
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Hi anaphase 2 and telophase two characteristics are
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similar to mitosis and finally
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four daughter cells will be produced to
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make it easier to distinguish mitosis and
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meiosis Pay attention to the following table mitosis
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where body cells or somatic cells while
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meiosis where it is in sex cells or
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game the purpose of mitosis for growth
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and repair or regeneration meiosis
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chromosome reduction the nature of daughter cells for
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mitosis is the same as the parent while
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meiosis is not the same as the parent chromosomes of
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daughter cells for mitosis 2N or diploid
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while meiosis n or haploid the number of
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daughter cells for mitosis is two and
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meiosis is four stages for
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mitosis only once, namely pma-9502
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Sis twice, namely pkbts one continue
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check mati2 good kids up to here the
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initial material In this first semester, yes,
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hopefully it is useful look forward to the continuation of the
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human reproductive organs Thank you If you have
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watched this video, don't forget to like
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comment share and subscribe,
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wassalamu'alaikum warahmatullahi
