2. Take out all of your cells. See if you can
arrange them in the correct order. Here are
some hints:
There will be 2 cellular divisions(PMAT)
As cells divide they get smaller
Which cell would you begin with?

4. --------space--------

5. Comparing Chromosomes in Metaphase Mitosis vs Meiosis
In mitosis, the chromosomes align independently of each’s matching chromosome. WHY?
However, in meiosis, matching
chromosomes form pairs and the
pairs align independently. WHY?
Because each new cell must receive one of each chromosome.
Because this division results in cells
with half of the required number
of chromosomes.

6. PI MI AI TI MEIOSIS: cell division to produce the reproductive
cells or GAMETES
Occurs only in organisms that reproduce sexually
Occurs in 2 stages:
MEIOSIS I: Results in 2 cells
with a reduction by half the total
number of chromosomes
MEIOSIS II: Results in 4 cells
with a division of the chromatids
A germ cell forms in testes or ovaries
It has the total # of chromosomes
referred to as a DIPLOID(2n) cell PI
HOMOLOGOUS chromosomes
pair forming a TETRAD(4 chromatids)
Tetrads are aligned
CROSSING OVER occurs and ends
of chromosomes are exchanged
resulting in new gene combinations MI AI
Crossing over is one of
several random processes that
increase variation in offspring
Tetrads are separated TI

7. NO G1 or S PII MII AII TII The 2 cells that result from meiosis I have
half the chromosomes
as the germ cell and are
HAPLOID(n)
NO G1 or S
Centrioles divide
and reform a new
meiotic spindle
Two of Mendel’s Laws
occur during meiosis:
Law of Independent
Assortment: homologous
chromosomes are
aligned randomly
during Metaphase I
PII
MII
Law of Segregation
Only 1 of 2
chromosomes
ends up in
each gamete
Chromatids are now
separated
AII
TII
4 haploid cells result from meiosis II

8. Cellular Division to Produce Gametes
MEIOSIS
Cellular Division to Produce Gametes

9. Law of Independent Assortment
Half of your chromosomes come from one parent and half from the other
In independent assortment these maternal and paternal chromosomes are aligned randomly in
the tetrad during metaphase I

10. Law of Segregation
When chromatids are separated in metaphase II, only 1 of the two ends up in each gamete
This too is a random process

11. Oogenesis and Spermatogenesis
Gamete Formation
Oogenesis and Spermatogenesis

12. Please label the sections below the fold and draw these diagrams
SPERMATOGENESIS
OOGENESIS
Please label the sections below
the fold and draw these diagrams
Not too small! Fill the space.
MEIOSIS I
MEIOSIS I
MEIOSIS II
MEIOSIS II

13. Now using the two colors you used for crossing over, draw in the
SPERMATOGENESIS
OOGENESIS
Now using the two colors you used
for crossing over, draw in the
chromosomes

14. on each of the 4 viable spermatozoa
Spermatogenesis
Meiosis to produce
the male gametes:
spermatozoa(sperm)
Division of the cytoplasm
is equal. All cells same size.
MEIOSIS I
MEIOSIS II
MEIOSIS II
Following meiosis a flagella and an enzyme cap are formed
on each of the 4 viable spermatozoa

15. Oogenesis Meiosis to produce the female gametes: ovum(egg) MEIOSIS I
Division of the cytoplasm
is unequal and which cell
receives the most is random.
MEIOSIS I
The larger cell will become the
ovum the smaller cell
is called a polar body
and is non viable.
POLAR BODIES
MEIOSIS II
MEIOSIS II
A polar body’s purpose is to hold
chromosomes, they are not viable.
POLAR BODY
The result of oogenesis is 1 viable ovum
and 3 nonviable polar bodies
OVUM

16. M & M Self Evaluation

17. Necking for
Repro rights
More won battle
To reproduce