Download Directed Reading A Section: The Characteristics of Cells

Name
Class
Date
Skills Worksheet
Directed Reading A
Section: The Characteristics of Cells (pp. 114–119)
Write the letter of the correct answer in the space provided.
______ 1. What is the smallest structural and functional unit of living things?
a. organ
b. cell
c. tissue
d. atom
CELLS AND THE CELL THEORY
______ 2. What did Robert Hooke build so he could see tiny objects?
a. a microscope
b. a telescope
c. a spectrascope
d. a camera
______ 3. What did Hooke call the little boxes that cork bark is made of?
a. crates
b. boxes
c. cells
d. atoms
______ 4. Why didn’t Hooke think animals were made of cells?
a. Hooke couldn’t see animal cells.
b. Animals do not have cells.
c. Animal cells have cell walls.
d. Animal cells are too dry.
Finding Cells in Other Organisms
______ 5. Where did Leeuwenhoek find what he called animalcules?
a. in animal blood
b. in bread dough
c. in cells
d. in pond scum
______ 6. What are the single-celled living things found in pond water called?
a. blood
b. proteins
c. protists
d. yeast
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt California Life Science
52
Cells: The Basic Units of Life
Name
Class
Date
Directed Reading A continued
The Cell Theory
______ 7. What theory says that living things are made of cells?
a. organic theory
b. tissue theory
c. structural theory
d. cell theory
______ 8. According to cell theory, what is the basic piece of all living things?
a. organ
b. tissue
c. blood
d. cell
______ 9. According to cell theory, where do all cells come from?
a. water
b. air
c. cells
d. food
CELL SIZE
A Few Large Cells
______ 10. What is one cell that is big enough to be seen without a microscope?
a. a chicken egg yolk
b. a cork bark cell
c. a blood cell
d. a bacteria cell
Many Small Cells
______ 11. What keeps a cell from getting too big?
a. surface area–to-volume ratio
b. size of the nucleus
c. amount of fluid in the cell
d. hardness of the cell wall
______ 12. What do cells use to bring in food and get rid of water?
a. their outer surface
b. their inner surface
c. their nucleus
d. their yolk
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt California Life Science
53
Cells: The Basic Units of Life
Name
Class
Date
Directed Reading A continued
______ 13. How do you figure out the surface area–to-volume ratio of a cell?
a. surface area ⴛ volume
c.
volume
surface area
b. surface area ⴚ volume
d. surface area
volume
PARTS OF A CELL
Use the terms from the following list to complete the sentences below.
nucleus
cell membrane
organelles
DNA
cytoplasm
14. The layer that protects every cell from its environment is
the
.
15. The fluid inside every cell is called
.
16. Structures in every cell that have specific jobs are called
.
17. At some time in its life, every cell has a(n)
.
18. Plant and animal cells store DNA in an organelle called
a(n)
.
TWO KINDS OF CELLS
Use the terms from the following list to complete the sentences below.
eukaroytic
prokaryotic
19. Cells that have a nucleus are
.
20. Cells that do not have a nucleus are
.
Prokaryotes
Write the letter of the correct answer in the space provided.
______ 21. What is a living thing with one cell and no nucleus called?
a. a prokaryote
b. a ribosome
c. a eukaryote
d. a protist
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt California Life Science
54
Cells: The Basic Units of Life
Name
Class
Date
Directed Reading A continued
______ 22. What kind of molecule is the DNA of a prokaryote?
a. long and circular
b. short and straight
c. long and spiral
d. short and boxlike
______ 23. What are tiny, round organelles made mostly of protein called?
a. cell membranes
b. ribosomes
c. cell walls
d. nuclei
______ 24. What kind of cells have strong, weblike cell walls?
a. prokaryotic
b. eukaryotic
c. archaic
d. amoebas
Eukaryotes
______ 25. What living things have cells with a nucleus inside a membrane?
a. prokaryotes
b. ribosomes
c. eukaryotes
d. bacteria
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt California Life Science
55
Cells: The Basic Units of Life