Answer Key
Cell Division Study Guide (Chapter 4.1-4.2)
Part I: Vocabulary. Using the word bank below, write the correct term next to its definition. Each word will
only be used once.
interphase
zygote
meiosis
budding
cytokinesis
chromosome
sperm
regeneration
cell cycle
sexual reproduction
haploid
diploid
meiosis I
meiosis II
mitosis
sister chromatids
egg
fertilization
asexual reproduction
fission
1. asexual reproduction type of reproduction where a new exact copy of one parent organism is formed.
2. cell cycle the “life cycle” of a cell, a series of events that take place from one cell division to the next.
3. chromosome structure in the nucleus that contains hereditary material (DNA).
4. sexual reproduction 2 sex cells, usually egg and sperm, come together in this type of reproduction.
5. diploid body cells that have 23 pairs (46 total) chromosomes in humans.
6. haploid sex cells with half the number of chromosomes (23 in humans).
7. fission form of asexual reproduction used by bacteria.
8. mitosis the process our body cells use to divide, the nucleus divides to form two identical nuclei.
9. sperm sex cell formed in the male reproductive organs.
10. egg sex cell formed in the female reproductive organs.
11. meiosis the process that produces haploid sex cells and ensures that offspring have the same diploid
number as the parent.
12. cytokinesis division of the cytoplasm following mitosis and the forming of 2 new cells.
13. budding form of asexual reproduction in which a small, exact copy of the adult grows from the parent.
14. fertilization joining of the egg and sperm.
15. interphase period of growth and development before cell division when chromosomes are duplicated.
16. meiosis I part of meiosis when the nucleus divides and produces two new cells with one duplicated
chromosome each.
17. meiosis II part of meiosis when the nuclei divide and chromatids separate, producing four cells with half
the number of chromosomes of the original nucleus.
18. regeneration form of asexual reproduction where a whole new organism grows from a piece of the parent.
19. sister chromatids when a chromosome is duplicated, the two identical parts are known as these.
20. zygote the cell that forms following fertilization.
Part II: Mitosis and Meiosis Concept Review Questions. Answer each question below in the space provided.
21. What are 3 differences between mitosis and meiosis? (answers vary…)
a. mitosis creates 2 new cells, meiosis creates 4
b. mitosis produces body cells, meiosis produces sex cells
c. same number of chromosomes after mitosis, half after meiosis
22. The process of mitosis:
a. Mitosis creates 2 new cells that are identical to the original parent cell.
b. If the original parent cell contained 46 chromosomes, the cells at the end of mitosis will have 46
chromosomes
c. Before mitosis begins, the cell is in the part of the cell cycle where growth, development, and
chromosome duplication takes place, known as interphase.
d. Prophase is the first phase of mitosis, where chromosomes become visible.
e. In metaphase, chromosomes line up along the middle of the cell.
f. During anaphase, chromosomes are pulled to opposite ends of the cell.
g. The final stage of mitosis is telophase, where 2 new nuclei are formed.
h. After mitosis, the cytoplasm is split during cytokinesis, resulting in 2 new cells.
23. The process of meiosis:
a. The process of meiosis results in 4 new cells each with half the number of chromosomes as the
original cell.
b. Meiosis creates sex cells (such as egg and sperm).
b. Meiosis is broken up into two parts, meiosis I and meiosis II.
c. After meiosis I, the nucleus divides, producing 2 new cells, each with one duplicated chromosome.
d. After meiosis II, the nuclei divide, and chromatids separate producing 4 new cells that are
considered haploid meaning they have half the normal number of chromosomes.
Part III: Short Answer: Answer each question below using sentences, or a bulleted list, where appropriate.
24. How is mitosis different in plant and animal cells? During cytokinesis, plant cells form a cell plate which will
ultimately lead to the cell wall, animal cells do not, they just pinch the cytoplasm, creating a furrow.
25. What is a zygote? Describe in detail how it is formed. A zygote is a fertilized egg. It is formed after one
sperm cell enters the egg cell. The zygote will then undergo mitosis to become a multicellular organism.
26. Compare/contrast what happens to chromosomes during metaphase I and metaphase II of meiosis. In
metaphase I, the chromosomes line up in pairs. In metaphase II they line up in a single line.
27. Why is cell division important for organisms? How one-celled organisms reproduce, replaces worn-out and
damaged cells, how multi-cellular organisms grow.