The document outlines 5 biology modules to be covered in the 4th quarter, including biodiversity, interactions, the digestive system, nutrition and wellness, and cellular reproduction and genetics. It then provides more details on the cellular reproduction and genetics module, including an overview of what students have learned in previous grades, key topics, suggested time allotment, cell division processes like mitosis and meiosis, Mendelian genetics principles, and Punnett squares.

1. 5 MODULES IN 4TH QUARTER
MODULE 1: BIODIVERSITY
MODULE 2: INTERACTIONS
MODULE 3: THE DIGESTIVE SYSTEM
MODULE 4: NUTRITION & WELLNESS
MODULE 5: CELLULAR REPRODUCTION
& GENETICS

2. BIOLOGY
Module 5

3. STORY LINE
• GRADE 3
Pupils learned that
living things reproduce
and certain traits are
passed on to their
offspring
GRADE 4
• Pupils learned that
humans, animals, and
plants go through life
cycles.
• Some inherited traits
may be affected by the
environment at certain
stages in their life
cycles.

4. STORY LINE
• GRADE 5
• Pupils learned how
flowering plants and
some non-flowering
plants reproduce.
• They were also
introduced to the sexual
and asexual modes of
reproduction.
GRADE 6
• Pupils learned how non-
flowering plants (spore-
bearing and cone-
bearing plants, ferns,
and mosses) reproduce.

5. STORY LINE
• GRADE 7
• After learning how
flowering and non-
flowering plants
reproduce, Grade 7
students learned that
asexual reproduction
results in genetically
identical offspring
whereas sexual
reproduction gives rise
to variation
GRADE 8
 Students will learn the
process of cell division by
mitosis and meiosis.
 They will understand that
meiosis is an early step in
sexual reproduction that
leads to variation.

6. Suggested Time allotment: 4 to 5 hours
KEY QUESTIONS:
•What are the different types of cell division?
•How are traits passed on to the next generation?

7. TOPICS INCLUDED:
Review on the Cell Function
Review on the Location of Chromosomes in
the CELL
Cell Cycle: Interphase (G1, S phase, G2)
Mitotic Phase
Meiotic Phase
Nondisjunction (Chromosomal Aberrations)
CLASSICAL GENETICS
-Mendelian Genetics
-Non-Mendelian Pattern of Inheritance
Sex-Linked Traits
Sex Chromosomes and Sex Determination

10. Cell Cycle
Makes up the entire life of the cell
• Consists of 2 major stages:
–Interphase
–Mitotic Phase
• Interphase
G0 -zero growth (Gap O)
G1- initial growth(Gap 1)
• S - synthesis
• G2 - growth 2 (Gap2)

12. Cell Cycle Part 1:
Interphase = normal phase of the cell.
 Chromosomes NOT
visible. – DNA in form
called chromatin
▪ Looks like spaghetti
 The nuclear
envelope/membrane
present
 DNA replication
 Cell growth

14. Mitosis - Review

16. Cell Cycle Part 2:
Cell Division
• Also known as Mitotic
Phase
• Where Mitosis and
Cytokinesis occur
• A continuous process
divided into 4 main stages
• Daughter Cells – 2 new cells
produced by cell division.

17. Mitosis = division of 1 diploid nucleus into 2
identical diploid nuclei
• All somatic/body
cells undergo
mitosis for growth,
repair or
replacement of old
cells
• Diploid cell (2n). –
cells with 2 sets of
chromosomes.
1 set-comes from
male parent
1 set-comes from
female parent

18. Mitosis in an actual cell

19. Prophase – 1st phase of mitosis.
• Chromatin materials becomes thicker and shorter because of
repeated coiling
• Chromosomes are now visible
• Centrioles form spindle
• Nuclear envelope/membrane and nucleoli breaks apart.
• The longest time to occur.

20. Metaphase – 2nd phase
 Chromosomes meet and align in middle or equator.
 Spindle fibers attach to centromere
 Nuclear envelope/membrane is gone.

21. Anaphase – 3rd phase
 Centromere splits at the center of the chromosomes.
 Chromatids move away from each other.
 Spindles pull chromatids apart
 The nuclear envelope/membrane still absent

22. Telophase – 4th phase
• Chromosomes begin to
disappear.
• Spindle fibers disappear
• Two new nuclear
envelopes/membranes
begin to form
• Nucleoli reappear.
• “reverse prophase”

23. Cytokinesis
• Division of the cell
membrane and
cytoplasm.
• Forms two new
Daughter cells

27. Mitosis - Overview

32. Interphase

34. Early Prophase

36. Late Prophase

38. Metaphase

40. Early Anaphase

43. Telophase - Cytokinesis

45. Telophase - Cytokinesis

46. Check for understanding!
• 11. Why are the onion root tip and the whitefish blastula useful
tissues for the study of cell division? . Why are the onion root tip and
the whitefish blastultissues for the study of cell division?
• These two tissues were actively dividing, so we could find cells
under going mitosis at different phases.

47. • 2. Distinguish between mitosis and cytokinesis.
Mitosis is the division of the nucleus (nuclear division)
produces 2 identical nuclei. Cytokinesis is the division of the
cytoplasm – produces 2 cells.

48. • 3. If a cell has 16 chromosomes when it is in G1, how
many chromosomes will there be in each daughter
cell following a mitotic cell division?
• 16

49. • 4. What are the genetic consequences of
mitotic cell division for the resulting daughter
cells?
Every cell is genetically identical to each other.
Produces 2 identical nuclei, each with the same number
and types of chromsomes as the parent cell.

50. • 6. How do plant and animal cells differ in the
execution of cytokinesis?
Why don’t plant cells undergo cytokinesis in
the same manner as animal cells?
• During cytokinesis plant cells form a cell
plate while animal cells form a cleavage
furrow.
• Plant cell has a rigid cell wall

51. Moving On…
• 7. List several important values or attributes that
mitotic cell division provides to multicellular life. In
other words, in what ways is mitotic cell division
useful for life?
• 8. List the 4 stages of the cell cycle and describe the
primary cellular activity in each stage.

52. Cell Division
• Reproduction
– Equal distribution of genetic
material to two daughter cells
• Growth
– Sexually reproducing
organisms develop from a
single cell (zygote)
• Repair
– Replace cells that die from
normal wear and tear or
accidents
A single-
celled
eukaryote
(amoeba)
reproduces
Sand dollar
embryo after
the egg
divided to
form 2 cells
Dividing bone
marrow cells
produce new
blood cells

53. More….
1. How many daughter cells are produced by mitosis?
2. How does the number of chromosomes in each
daughter cell compare with the number of
chromosomes in the original parent cell after mitosis?
3. When are chromosomes replicated?
4. During cytokinesis plant cells form a _________
while animal cells form a ____________.

54. ANSWERS:
1. How many daughter cells are produced by mitosis? 2
2. How does the number of chromosomes in each
daughter cell compare with the number of chromosomes
in the original parent cell after mitosis? Same number
and type of chromosomes.
3. When are chromosomes replicated? Interphase,
specifically S-phase
4. During cytokinesis plant cells form a cell plate while
animal cells form a cleavage furrow.

55. Meiosis
Two rounds of cell division
In humans, each daughter
cell has 23 chromosomes

56. Many possible combinations of
chromosomes are possible
Random assortment
Crossing over

57. Not identical in human males and females
Feature Males Females
When does meiosis begin?
How long does each step
take?
Begins at puberty
Each step takes about the
same time (~64 days total)
Begins during embryonic
development
May remain in meiosis I for
decades (may never
complete meiosis)
How is meiosis completed? Spermatocytes will
complete meiosis
Meiosis II happens only
with fertilization
How many gametes are
formed?
4 spermatids are formed One ovum is formed

58. ANIMATION OF MEIOSIS

61. Classical Genetics
MENDELIAN PRINCIPLES OF
INHERITANCE

64. Mendel’s
Genetics
Experiment
with Peas

66. Pea Characters Investigated

67. Pea Characters Investigated

68. MENDEL’S RULE OF HEREDITY

69. PUNNETT SQUARE: Monohybrid Cross- single trait factor
EXAMPLE : seed shape
round (RR) is dominant over wrinkled (rr)
Problem: Predict the outcome of a cross when a homozygous
dominant round pea is cross with a homozygous wrinkled pea
plant
R
R
r
r
Rr Rr
Rr Rr
PR: 100 %
ROUND
GR: 100 % Rr

77. Gametes RY Ry rY ry
RY
Ry
rY
ry
Dihybrid Cross: two factor cross
Seed Shape: Round (RR). Wrinkled
Seed Color: yellow (YY) and green (yy)
Parents’ genotype: RrYy x RrYy
RRYy
RRYY RRYy
RrYY RrYy
RrYy
RrYy
RrYy
RRyy
RrYY
rryy
rrYY
Rryy
Rryy
rrYy
rrYy

78. Phenotype Round &
Yellow
Round &
Green
Wrinkled &
Yellow
Wrinkled
& green
GENOTYPIC
RATIO
RRYY-1
RRYy-2
RrYy- 4
RrYY-2
RRyy -1
Rryy-2
rrYY- 1
rrYy-2
Rryy-1
PHENOTYPIC
RATIO
9 3 3 1

85. A or O
A or AB

88. “Tell me and I will
forget,
Show me and I might
remember,
Involve me and I will
understand.”
Chinese Proverb
Thank You