Mitosis & Meiosis
• Unit #7
1. What is condensed and coiled
up DNA called?
chromosomes
2. What does the DNA wrap
around?
• histones
3. One copy of the DNA is called?
• chromatids
4. When the two chromatids are put
together, they produce a
• chromosome
________.
5. What holds the chromatids
together?
• centromere
6. What is the segment of DNA that
codes for a trait?
• gene
7. In a human, number of individual
46
chromosomes ____
Number of pairs of chromosomes 23
__
8. How many chromosomes are
contributed by the mother’s
gamete?
____
23
Father’s gamete?
____
23
Total for the new zygote? ____
46
9. Allele combinations for
XX
normal female- ____
Normal male- ____
XY
10. In a human, chromosome pairs
autosome
1-22 are _________
chromosomes.
11. In a human, chromosome pair #23
Sex chromosomes. In a female
are ___
egg gametes
they are __________(specific
type)
and in a male they are
Sperm gametes
______________(specific
type).
12. Homologous chromosomes are
autosome pairs that are the
same ____,
carry the
shape
Size _____and
_______for the same trait.
information
13. Diploid cells which are
• _____________
body/somatic body (type) cells have
___
46 (number) individual
chromosomes and 23
__(number) 0f
pairs.
14. Haploid cells which are
sex/gametes
23
__________(type)
cells have ____
(number) individual chromosomes
0 (number) of pairs.
and ____
15. Mitosis occurs in body/somatic
___________
cells and meiosis occurs in
_______
cells.
Sex
16. What are the 4 reasons for cells
to divide?
•
•
•
•
-replace dead/old cells
-repair existing cells
-for growth of the organism
-to maintain healthy cell size
17. How long is Interphase?
• ~ 90% of cell life
18. Do all cells leave Interphase?
Give an example
• No, like the nerve cell stays in G0
19. What happens in G1 part of
Interphase?
• Cell grows and makes
centrioles/organelles
20. What is replicated in the S
phase?
• DNA
21. What happens in G2 part of
Interphase?
• Final preparation for cell division
22. What are the 3 main events in
prophase?
– -nuclear membrane & nucleolus fad and
disappear
– -centrioles appear & move to opposite ends
releasing spindle fibers
– -chromosomes form
23. What 2 events in metaphase?
• -Chromosomes line up in the middle
(equator)
• -Spindle fibers attach to centromeres
24. What are the 3 main events in
anaphase?
• -Centromeres split in half
• -Chromosomes split/separate into
chromatids
• -Centrioles pull in spindle fibers &
chromatids to opposite ends
25. What are the 3 main events in
telophase?
• -Centrioles & spindle fibers fade and
disappear
• -nuclear membrane reappears and forms
around chromatids
• -cells stretches out
26. What happens in cytokinesis?
• Splitting of the cytoplasm and cell
membranes into 2 new cells
27. What divides the plant cell in
cytokinesis?
• Cell plate
28. What divides the animal cell in
cytokinesis?
• Cleavage furrow
29.What are the 2 events that
are the same in Prophase I to
mitosis prophase?
• -centrioles & spindle fibers appear
• -nuclear membrane & nucleolus disappear
29. cont.The one major difference
that causes genetic diversity?
• Crossing over-exchange of genetic
material between homologous
chromosome pairs
30. Draw crossing over.
31.What is the event in metaphase
I that is similar to metaphase in
mitosis?
• Spindle fibers attach to the centromeres
32.What is the event that causes
genetic diversity in metaphase I?
• Lining up randomly
33.What happens in anaphase I?
• Chromosmes separate to opposite sides
(different than anaphase in mitosis because
entire chromosomes not chromotids seperate)
34.What 2 events happen in
telophase1? (Underline which one
is a temporary process)
• -nuclear membrane forms around
chromosomes
• -Spindle fibers & centrioles disappear
35.What happens after telophase
that splits the cells?
• cytokinesis
36.What is meiosis II very similar to?
• mitosis
37.What are the 3 main differences
between mitosis and meiosis II?
• -starts with 2 daughter cells not just one
• -ends with 4 non identical daughter cells
not 2 identical daughter cells
• -each cell formed has only 23
chromosomes not 46 (haploid not diploid)
38. Recopy your Venn diagram
comparing mitosis to meiosis.
39.Male meiosis also known as
____________
spermatogenesis produces
__(number)
_____
4
sperm (type) cells.
40.Female meiosis also known as
_______
oogenesis produces
__(number)
__________(type)
1
mature egg
cell.
41.What two phases cause
oogenesis to produce only
one mature cell?
– -cytoplasm splits unevenly in telophase I
– -telophase II
42. Why is it important to have a large
egg cell?
• To develop an organism
43. What is it called when
offspring are produced from
only 1 parent?
• Asexual reproduction
44.What is it called when offspring
are produced from the
combination of gametes from
2 parents?
• Sexual reproduction
45.What is the process of fusing
sperm and egg?
• Fertilization
46. What is the new cell called
from the joining of sperm and
egg?
• Zygote