2. TOPICS :
• Definition of Reproduction
• Purpose of Reproduction
• Growth and development
• Cell Division : Definition, Purpose,
Types, and Process
3. DEFINITION
The reproductive system or genital system is the
system of sex organs in an organism that work
together for the purpose of sexual reproduction.
7. 7
CELL DIVISION
• Cell division is the process by which a cell divides into two or more cells.
Cell division is a way for cells to multiply themselves or what is called
reproduction.
• Living things can grow and develop because the cells in their bodies
experience an increase in number, increase in length, increase in volume
and increase in cell mass, so that living things can be taller and bigger.
8. PURPOSES OF CELL DIVISION
8
The process of cell division has several
purposes:
Regeneration of damaged and dead cells
Helps the process of growth and
development
Helps the breeding process
(reproduction)
Variation of new individuals
9. TYPES OF CELL DIVISION
9
DIRECT DIVISION : AMITOSIS
INDIRECT DIVISION : MITOSIS & MEIOTIC
10. Amitosis cell division occurs in low-level living things such as eukaryotic and prokaryotic
unicellular organisms. The process that occurs in amitosis cell division does not go through
the stages of division.
The main characteristics or features of cell division by amitosis are :
1. Eukaryotic organism
2. Unicellular organisms (e.g., amoeba, paramecium, blue-green algae)
3. Each cell divides into 2 cells
Amitosis 10
11. MITOSIS
11
Mitosis division is a cell division event that
produces two child cells with the same
number of chromosomes as the parent cell.
Characteristics of mitosis division:
1. occurs once
2. the number of child cells is two
3. diploid (2n)
4. same characteristic with parents
5. somatic cells
6. the process is PMAT (Prophase,
Metaphase, Anaphase, Telophase)
14. MITOSIS
INTERPHASE PROPHASE METAPHASE ANAPHASE TELOPHASE
• Fase G1 : fase
pertumbuhan dan
perkembangan sel.
• Fase S : fase
replikasi/duplikasi
DNA.
• Fase G2 : fase
persiapan
pembelahan, sintesis
protein.
• Replication of
sentrosom
• Thickening and
shortening of
chromatin into
chromosomes.
• Duplication of
chromosom.
• the nucleus and
nuclear membrane
of the cell are no
longer visible
• the chromatid pair
moves to the center
of the cell nucleus.
• separation of
chromatids by
spindle threads
toward opposite
poles.
• Cytokinesis (division
phase) occurs.
• chromosomes have
reached their
respective poles.
• The spindle threads
begin to disappear.
• chromosomes thin
out and turn back
into chromatin.
15. MEIOSIS
15
Meiosis division is a cell division that produces
child cells with half the number of chromosomes
as the parent.
Characteristics of meiosis division:
1. occurs twice
2. the number of child cells four
3. haploid (n)
4. Not the same as its parent due to undergoing
genetic recombination
5. gamet cells
6. the process is PMAT 1 and PMAT 2
17. MEIOSIS
PROPHASE 1
• Leptonema: Chromatin threads shorten and thicken, and easily
absorb dyes. Chromosomes undergo condensation.
• Zigonema: The centromere splits into two and moves towards the
opposite pole. Meanwhile, homologous chromosomes pair together
(synapse).
• Pakinema: Chromosome duplication occurs.
• Diplonema: Homologous chromosomes move away from each other,
there is an X-model attachment called chiasm and is where
'Crossing Over' occurs.
• Deaconesis: Spindle threads are formed, two centrioles arrive
at opposite poles, content membrane and nucleus disappear.
• The centrosome that splits into two centrioles moves to the
opposite pole of the cell.
• Chromatids move to the plane of division.
18. MEIOSIS
METAPHASE 1
• Homologous chromosome pairs line up in the equatorial region.
• The centromeres go to the poles and secrete spindle threads.
• At this stage, chromosomes line up on the equatorial or cleavage
plane.
19. MEIOSIS
ANAPHASE 1
• Homologous chromosomes separate and move to opposite poles.
• The spindle threads and the entire cell content extend towards the
poles.
• In this third phase, the chromatids separate and move to
opposite poles.
20. MEIOSIS
TELOPHASE 1
• Homologous chromosomes separate and move to opposite poles.
• The nuclear membrane begins to re-form.
• Cytokinesis causes the formation of two haploid child cells.
• In the last phase, chromatids will form into chromosomes.
21.
22. SUMMARY
Cell Division 22
Aspect Mitosis Meiosis
Purpose
Somatic cell division; growth, repair,
and asexual reproduction.
Gamete (sex cell) formation; sexual
reproduction.
Number of Divisions
One division, resulting in two
identical child cells.
Two divisions, resulting in four
genetically diverse child cells.
Chromosome Number
child cells have the same
chromosome number as the parent
cell (2n).
child cells have half the chromosome
number as the parent cell (n).
Genetic Diversity
No genetic variation; identical
genetic information in child cells.
Introduces genetic variation through
crossing-over and random
assortment.
Occurrence
Occurs in somatic cells throughout
an organism's life.
Occurs in germ cells (reproductive
cells) during the formation of
gametes.
Role
Growth, tissue repair, asexual
reproduction.
Produces haploid gametes for sexual
reproduction.
Stages
Prophase, Metaphase, Anaphase,
Telophase.
Meiosis I (Prophase I, Metaphase I,
Anaphase I, Telophase I) Meiosis II
(Prophase II, Metaphase II,
Anaphase II, Telophase II)
