tab de note cell division latest.docx

BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION

SUB TOPIC/ TERMINOLOGY DIAGRAM & DESCRIPTION
LEARNING
OUTCOME

3.1 THE Mitosis Cell division:
CONCEPT OF -division of genetic • The reproduction of cells. (ref: Campbell 9th ed.)
CELL DIVISION material in the • Requires the distribution of identical genetic material (DNA) from the parent cells to
nucleus followed
Learning by cytokinesis to daughter cells (except for meiosis).
Outcome: form 2 identical • The cell division process is an integral part of cell cycle, the life of a cell from the time it is first
daughter cell with
a) Explain the parent cells. formed from a dividing parent cell until its own division into two cells.
cell division

Meiosis
-a type of nuclear
division that
results four haploid
daughter cell each
having a nucleus
containing the half
chromosome
number (n) of
parent cells (2n)

Cytokinesis
-division of the
cytoplasm to form
two separate
daughter cells.

1

b) State BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
importance of
cell division in IMPORTANCES :
living
organism Genetic stability (mitosis)

•There is no variation in genetic information.
•Daughter cells are genetically identical to the parent cell.

Cell Growth & Development (mitosis)

•The number of cells within an organism increases.
•This is the basis of growth in multicellular organisms.

Cell replacement (mitosis)

•Multicellular organisms also use cell division to renew cells.

Regeneration (mitosis)

•Some animals are able to regenerate the whole parts of the body, such as tail in lizards & arms in starfish.
•Production of the new cells also involve cell division.

Asexual reproduction (mitosis)

•Mitosis is the basis of asexual reproduction, the production of new individuals of a species by one parent
organism.

Half the chromosome number (meiosis)

 Meiosis divide the chromosome number by half from the parental chromosome.
 E.g.: 46 chromosomes (parents) to 23 chromosomes (gamete).

Increased genetic variations (meiosis)

 Leads the genetic variations in daughter cells due to crossing over during prophase I & independent assortment
during metaphase I.

2

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

c) State
importance of
cell division
in living
organism

3

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME Cell cycle DIAGRAM & DESCRIPTION
Sub topic: -complete sequence
of events in the life of • The cell cycle consists of two main phases:
3.2 an individual diploid o Interphase (non dividing phase/ the resting phase)
the cell cell. o Mitotic (M) phase (dividing phase)
cycle
• The M phase includes mitosis & cytokinesis.
Learning o Mitosis - Division of the nucleus.
Outcome: o Cytokinesis - Division of the cytoplasm.

a) Explain INTERPHASE
the stages (the longest phase in cell cycle)
in cell
cycle: 1. G1 Phase (First Growth Phase)
Interphase  Cells increase in size/ cell grows.
and mitotic  Volume/ mass of cytoplasm is increased
phase.  Synthesis of cytoplasmic organelles such as

mitochondria
 Synthesis of carbohydrate, lipid & RNA

2. S phase (Synthesis Phase)
 Replication/ synthesis of DNA occurs.
 Resulting in the DNA content of the cell being

doubled.

3. G2 Phase (the 2nd Growth Phase)
 Energy stored are increased.
 Continue increases in the number of organelles

such as mitochondria, Golgi body & ER.
 Increases in the size of nucleus

4

BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION

SUB TOPIC/ TERMINOLOGY DIAGRAM & DESCRIPTION
LEARNING
OUTCOME -Mitosis PHASE EVENT/BEHAVIOUR
3.3 division of the
Mitosis genetic material in Prophase
the nucleus followed
Learning by cytokinesis. • The nuclear envelope
Outcome: • Nucleolus disintegrate.
• Chromosome condensed, shorten and
a) Describe
the four thicken (make it visible under light
stages of microscope).
mitosis • Each duplicated chromosome appears as
two identical sister chromatids joined at
the centromere.
• The mitotic spindle/ microtubules are
begin to form.
• Centrosome move away from each other to
opposite pole by lengthening microtubules
between them.

5

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

Metaphase

• Chromosomes as a sister chromatids
moves & align on the metaphase plate
(equatorial plate of cell’s midline).

• The chromosome’s centromeres lie on the
metaphase plate.

• Microtubule attach to kinetochore of sister
chromatid at centromere known as
kinetochore microtubule.

• Centromere at opposite pole.

6

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

Anaphase
 Centromere split
 Chromosome as sister chromatids

separate and move to opposite pole.
 The daughter chromosome move toward

opposite poles as individual
chromosome.
 The cell elongates as the non-
kinetochore lengthen, preparing for
cytokinesis.

Telophase

• The daughter chromosomes reach their
opposite poles of the cell.

• Nucleolus are reformed in the cell.

• New nuclear envelope reformed.

• The spindle fibers disintegrates.
• The chromosome become less

condensed, which are uncoil & lengthen,
thus becoming invisible again.

7

BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION

SUB TOPIC/ TERMINOLOGY DIAGRAM & DESCRIPTION
LEARNING
OUTCOME CYTOKINESIS

b) Describe The division of the cytoplasm to form two separate daughter cells.
briefly the
cytokinesis The division of cytoplasm occurs by the late telophase, so the identical daughter cells appear
process in
animal shortly after end of mitosis or meiosis II
and plant
cell. Cytokinesis in animal cell Cytokinesis in plant cell

Formation of cleavage furrow Formation of cell plate
-Cleavage grow from outside to inside (pulled -Cell plate grow from inside to outside

inward) (expands outward)

Cell membrane is pulled inwards by the Plants cells formed vesicles derived from Golgi
cytoskeleton body that contain material to construct cell wall in
A shallow groove is formed in the cell surface the cells
near the old metaphase plate. The vesicles enlarge and fuse to form cell plate
A contractile ring forms on the cytoplasmic side across the midline of cell.
of the furrow This will form two membrane which grow laterally
Microfilaments / actin and myosin of the ring / expands outward and
contract, thus reduce the diameter of the ring Forming two plant cells, each with its own plasma
Cells are completely separated / two cells are membrane
formed A new cell wall forms between the membranes

8

BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION

SUB TOPIC/ TERMINOLOGY DIAGRAM & DESCRIPTION
LEARNING
OUTCOME Homologous MEIOSIS
3.4 chromosome DEFINITION: process by which one diploid eukaryotic cell divides to generate four haploid cells often called
Meiosis A pair of
chromosomes of the gametes.
– same length,
Learning centromere position, This process involved two cycle of nuclear divisions, known as
Outcome: and staining pattern  Meiosis I (the first meiotic division)
that possess genes  Meiosis II (the second meiotic division)
a) Describe for the same
the stages characters at PHASE - Meiosis I Event/ chromosomal behaviour
of meiosis corresponding loci.
I and Prophase I
meiosis II
 Chromosomes begin to condense.

 Centrosomes move away from each other

towards opposite end of the cell.

 Nucleolus & nuclear envelope have

b) Compare Crossing-over disintegrated
mitosis Process of
and exchanging genetic  Spindle fibers form.
meiosis material between two
non-sister  Synapsis occur
chromatids.  Homologous pair up along their lengths to

Tetrad produce bivalent/tetrad.
/Bivalent/synapsis  Crossing over occur at the chiasmata.
Paired homologous  At the end of crossing over in prophase I,
chromosome that
consist of 4 sister chromatids of a chromosome are no
chromatids. longer genetically identical.

Synapsis
Pairing up
homologous
chromosome

9

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

Crossing over 10

Sub topic: Kinetochore
Protein a protein
3.4 • structures at the
Meiosis centromeres of two
homologs.
Learning
Outcome:

a) Describe Chiasma
point at which paired
the stages I – homologous
of meiosis chromosomes remain
in contact as they
and meiosis begin to separate
during prophase I of
II meiosis, forming a
cross shape (X
a) Compare shape).
mitosis -point of crossing-
and over occur.
meiosis

Sub topic:

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME Metaphase I DIAGRAM & DESCRIPTION
3.4 Anaphase I
Meiosis  The pair of homologous chromosomes
(bivalents) move and aligned on
Learning metaphase plate.
Outcome:
 Both chromatids of the homologue are
a) Describe attached to kinetochore microtubules from
the one pole, those of the other homologue are
stages of attached to kinetochore microtubule from
meiosis I the opposite pole.
and
meiosis II  The kinetochore microtubule starts to
shorten.
b) Compare
mitosis  The paired homologous chromosomes
and separate and pull to opposite poles.
meiosis
 Causing the chiasmata to break.
 This separate the chromosome into two

haploid sets, one set at each end of the
spindle.
 Each chromosome still contains a pair of
sister chromatids.
 The centromere do not split/divide.

11

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION
Telophase I

Sub topic:  Chromosome reach at opposite poles of the cell;
 The chromosome generally decondensed/ uncoil into chromatin.
3.4  The nuclear envelope reforms and surround each haploid set of daughter nuclei.
Meiosis  Spindle fibre usually disappear.
 Nucleolus reform.
Learning
Outcome:  Cytokinesis usually occur simultaneously with telophase I forming two haploid daughter cells.

a) Describe
the
stages of
meiosis I
and
meiosis II

b) Compare
mitosis
and
meiosis

12

BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION

SUB TOPIC/ TERMINOLOGY DIAGRAM & DESCRIPTION
LEARNING
OUTCOME

PHASE -- MEIOSIS II EVENT/BEHAVIOUR

Prophase II  In each haploid daughter cells,
nucleoli and nuclear envelopes
Sub topic: disintegrate

3.4  Chromosome shorten and
Meiosis thicken again.

Learning  Centrioles, if present move to
Outcome: opposite poles of the cell at
the end of prophase II.
a) Describe
the disintegrate  Chromosomes as sister
stages of Metaphase II chromatids move and align
meiosis I at metaphase plate.
and
meiosis II  Because of the crossing-over
in meiosis I, the two sister
b) Compare chromatids of each
mitosis chromosome are not
and genetically identical.
meiosis
 The kinetochores of sister
chromatids are attached to
microtubules extending from
opposite poles.

Sub topic:

13

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME Anaphase II DIAGRAM & DESCRIPTION
3.4 Telophase II
Meiosis  Spindle fibre begins to
shorten.
Learning
Outcome:  The centromere divide/split
and allow sister chromatids to
a) Describe separate.
the
stages of  The daughter chromosome
meiosis I move toward opposite poles
and as individual chromosome.
meiosis II
 The cell elongates as the non-
b) Compare kinetochore lengthen,
mitosis preparing for cytokinesis.
and
meiosis  Nuclear envelope and
nucleolus reform
Sub topic:
 The chromosome begin to
decondensed into chromatin.

 Cytokinesis occur.
 The meiotic division of one

parent cells, each with haploid
set of chromosomes.
 Each of four daughter cells is
genetically different from one
another daughter cells and
from the parent cell.

14

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION
3.4
Meiosis

Learning
Outcome:

a) Describe
the
stages of
meiosis I
and
meiosis II

b) Compare
mitosis
and
meiosis

15

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

Sub topic: 16

3.4
Meiosis

Learning
Outcome:

a) Describe
the
stages of
meiosis I
and
meiosis II

b) Compare
mitosis
and
meiosis

SUB TOPIC/ TERMINOLOGY BIOLOGY 1 /DB 014/NF2F/3.0 CELL DIVISION
LEARNING
OUTCOME DIAGRAM & DESCRIPTION

Sub topic: SUMMARY OF MITOSIS AND MEIOSIS PROCESS

3.4 17
Meiosis

Learning
Outcome:

a) Describe
the
stages of
meiosis I
and
meiosis II

b) Compare
mitosis
and
meiosis