Name: ________________________________________ Pd. _________
Cell Divison: Mitosis and Meiosis Study Guide
Biology
Mitosis
1.
Why are cells small rather than large?
-the larger a cell is, the longer it takes for materials to move into and out of the cell
-smaller cells are more efficient
2.
Name two reasons that cells must divide.
-cells get bigger and the number of cells gets larger
-old cells die and need new cells to replace them
3.
What is the cell cycle?
-regular sequence of growth and division that cells undergo
4.
What are the three parts of the cell cycle?
-interphase
-mitosis
-cytokinesis
5.
What happens during G1 of interphase?
-Growth phase- cell doubles in size, cell produces all of the structures it needs to carry out its functions
6.
What happens during S of interphase?
-DNA Copying- cell makes a copy of its DNA (replication)
7.
What happens during G2 of interphase?
-Preparation – cell prepares to divide, cell produces structures needed for cell division
8.
List the four stages of mitosis in order.
-Prophase
-Metaphase
-Anaphase
-Telophase
9.
What happens during prophase?
-chromatin condenses into chromosomes
-chromosomes look like an “X”
-nucleus disappears
-spindle fibers form in the cytoplasm and attach to sister chromatids
10. What happens during metaphase?
-sister chromatids are pulled to the center of the cell and line up in the middle of the cell
11. What happens during anaphase?
-spindle fibers begin to shorten, the sister chromatids are pulled to the opposite ends of the cell
12. What happens during telophase?
-sister chromatids arrive at the opposite poles of the cell and begin to unravel
-new nucleus begins to form
13. What is cytokinesis?
-division of the cytoplasm
-results in two separate cells with identical nuclei
Name: ________________________________________ Pd. _________
Cell Divison: Mitosis and Meiosis Study Guide
Biology
14. Why does cytokinesis happen differently in plant and animal cells?
-animal cells-microfilaments “pinch” the cytoplasm
-plant cells- a cell plate forms between the two daughter nuclei
15. What is the result of mitosis? (What do you get at the end of mitosis?)
-2 identical daughter cells (chromosomes are identical)
16. Explain the relationship between chromatin and chromosomes.
-chromatin is composed of DNA and proteins, it makes up the chromatid
-chromosomes are composed of the condensed chromatin
17. During which stage of the cell cycle (interphase, mitosis, or cytokinesis) are chromosomes visible?
-prophase
18. What are sister chromatids?
-a copy of the chromosome (sister chromatids are identical to one another), held together by a centromere.
19. Identify whether each of the following cells is in prophase, metaphase, anaphase, or telophase.
_____________metaphase____________________
___prophase______________________
_____________telophase__________
_______anaphase_________________
Name: ________________________________________ Pd. _________
Cell Divison: Mitosis and Meiosis Study Guide
Biology
Meiosis
1.
define and explain the following terms:
o
gametes –sex cells (sperm and egg), haploid
o
somatic cells –body cells (all other except sperm and egg), diploid
o
zygote – formed by the fusion of an egg and a sperm
o
fertilization – the fusion of gametes
o
meiosis- the process of cell division that produces haploid gametes (half the number of
chromosomes
o
synapsis -Following chromosome replication, the homologous chromosomes pair all along their length
o
crossing over- is a complex series of events in which DNA segments are exchanged between
nonsister or sister chromatids.
o
reduction division - The chromosomes are not copied in between the two divisions. At the end of
meiosis, each cell contains one half the genetic material. (haploid or “n”)
o
independent assortment -random chromosomes move to each pole; some may be maternal and some
may be paternal
o
haploid – 1 copy of each chromosome ; “N”
o
diploid – 2 copies of each chromosome (one from mom and one from dad); “2N”
o
homologous chromosomes -two copies of each chromosome (one copy from the sperm and one copy
from the egg)
Name: ________________________________________ Pd. _________
Cell Divison: Mitosis and Meiosis Study Guide
Biology
2. How many rounds of cell division do diploid cells undergo in meiosis?
2: Meiois 1 and Meiosis 2
3. Describe the cells produced after meiosis 1.
-2 haploid cells
-each cell contains sets of chromosomes that are different from one another.
4. Describe the cells produced in meiosis.
4 haploid daughter cells – all genetically different from one another
5. Compare the cells produced by meiosis and mitosis.
-mitosis produces 2 diploid cells all identical to one another and the parent cell
-meiosis produces 4 haploid cells all genetically unique
6. State when crossing over occurs.
–prophase 1
7. Describe when replication occurs.
before meiosis 1 only
8. State how many chromosomes a human somatic cell and a human gamete have. somatic cell: 46,
gamete: 23
9. Describe how meiosis 1 differs from meiosis 2.
-meiosis 1 separates homologous chromosomes, meiosis 2 separates sister chromatids