Download Section 2-3 Book C

Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Worksheet Section 2-3 (C)
Section: The Cell Cycle
1. Why is it important for your body to produce millions of new cells by the time
you finish reading this sentence?
__________________________________________________________________________________________
__________________________________________________________________________________________
THE LIFE OF A CELL
_____ 2. When does the cell cycle begin?
a. when the cell is formed
b. when the cell divides
c. when the cell uses energy
d. when the cell takes in oxygen
_____ 3. When does the cell cycle end?
a. when the cell is formed
b. when the cell divides and makes new cells
c. when the cell uses energy
d. when the cell takes in oxygen
6. A cell without a nucleus is a(n) ______________________ cell.
7. A cell with a nucleus is a(n) ______________________ cell.
8. A chromosome is the ring of DNA in a(n) ______________________ cell.
9. A chromosome is made up of DNA and protein in the nucleus of a(n)
______________________ cell.
MATH SKILLS
5. Cell A takes 6 h to complete division. Cell B takes 8 h to complete division.
After 24 h, how many more copies of cell A would there be than cell B? Show
your work below.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
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The Cell in Action
Name ______________________________ Class ___________________ Date __________________
Directed Reading A continued
10. Are bacteria prokaryotic cells or eukaryotic cells?
__________________________________________________________________________________________
11. Bacteria create new cells through a kind of cell division called
______________________
12. When binary fission is complete, the result is two cells that each contain one
copy of .______________________
13. The chromosomes of eukaryotic cells have more
______________________than do the chromosomes of prokaryotic cells.
14. Humans have ______________________ chromosomes, while fruit flies have
only .______________________ Potatoes have ______________________
chromosomes.
15. Chromosomes that line up in pairs are called ______________________.
16. What do pairs of homologous chromosomes have in common?
__________________________________________________________________________________________
__________________________________________________________________________________________
17. In the beginning of the eukaryotic cell cycle, the cell grows and duplicates its
______________________ and ______________________.
18. After a chromosome is duplicated, the two copies are called
______________________.
19. Where are chromatids held together?
__________________________________________________________________________________________
20. Chromatids in eukaryotic cells separate during a process
called______________________
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
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The Cell in Action
Name ______________________________ Class ___________________ Date __________________
Directed Reading A continued
MITOSIS AND THE CELL CYCLE
_____ 24. Before mitosis begins, what paired cell structures are copied?
a. the cell plates
b. the chromosomes
c. the cell membranes
d. the nuclear membrane
Use the diagram below to help answer questions 25-30, which describe
the phases of the cell cycle. Write the correct phase in each blank,
using “Interphase,” “Mitosis Phase 1,” “Mitosis Phase 2,” “Mitosis
Phase 3,” “Mitosis Phase 4,” or “Cytokinesis.”
_____________________ 25. Chromatids separate and move to opposite sides of
the cell.
_____________________ 26. The chromosomes line up along the equator of the
cell. Homologous chromosomes pair up.
_____________________ 27. Before mitosis begins, chromosomes are copied.
_____________________ 28. A nuclear membrane forms around the two sets of
chromosomes, and the chromosomes unwind.
Mitosis is complete.
_____________________ 29. Mitosis begins. The nuclear membrane dissolves.
Chromosomes condense into rodlike structures.
_____________________ 30. In cells that lack a cell wall, the cell pinches in two.
In cells that have a cell wall, a cell plate forms
between the two new cells.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
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The Cell in Action
Name ______________________________ Class ___________________ Date __________________
Assessment
Section 2-3 (C) Quiz
Section: The Cell Cycle
Match the correct definition with the correct term. Write the letter in the space
provided.
_____ 1. the process of cell division that forms two
nuclei
_____ 2. the life stages of a cell
a. cytokinesis
b. chromosome
c. cell cycle
_____ 3. pairs of similar chromosomes
_____ 4. the structure in which DNA, the
hereditary material that controls cell
activities, can be found
d. mitosis
e. homologous
chromosomes
_____ 5. the division of cytoplasm
Write the letter of the correct answer in the space provided.
_____ 6. Cells need to produce new cells in order to
a. create new chromosomes.
b. replace cells that have died.
c. obtain energy from sunlight.
d. release energy from food.
_____ 7. Organelles and chromosomes are copied during
a. the first stage of the eukaryotic cell cycle.
b. the second stage of the eukaryotic cell cycle.
c. the third stage of the eukaryotic cell cycle.
d. cytokinesis.
_____ 8. During cytokinesis in plant cells,
a. a cell plate forms inside the two new cells.
b. the cell loses some of its DNA.
c. a cell plate forms, and the cell splits in two.
d. the cell wall breaks.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
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The Cell in Action