CHAPTER 4 CELLS: THE BUILDING BLOCKS OF LIFE
SECTION 4–1 What Is Life? (pages 122-129) This section explains the
characteristics of living things and what living things need to survive.
The Characteristics of Living Things (pages 122–125)
1. What is an organism?
2. List six characteristics that all living things share.
_______________
_______________
_______________
_______________
_______________
13. Look carefully at Exploring the Experiments of Redi and Pasteur on
pages 126–127. What letter is the independent variable in Redi’s
experiment? a. meat
b. jars
c. time given
d. flies
14. Is the following sentence true or false? Louis Pasteur used experiments
to show that bacteria arise from spontaneous generation.
The Needs of Living Things (pages 127–129)
15. Complete this concept map to show what living things need to survive.
_______________
3. The basic unit of structure and function in an organism are
_____________.
4. Is the following sentence true or false? An organism’s structure is the
way it is made.
5. Is the following sentence true or false? An organism made of many cells
is a unicellular organism.
6. Which letter is the most abundant chemical in cells?
a. proteins b. carbohydrates c. water d. nucleic acids
16. Organisms that make their own food are called
______________________.
7. Is the following sentence true or false? The cells of organisms use energy
for growth and repair.
17. Organisms that cannot make their own food are called
_________________________.
8. All organisms can _________________, or produce offspring that are
similar to the parents.
18. Is the following sentence true or false? Living things can live without
water for long periods of time.
Life Comes From Life (pages 125–126)
9. The idea that living things can come from nonliving sources is called
________________________________________.
19. What property of water makes it vital to living things?
10. Where did people think frogs sprouted from?
20. Is the following sentence true or false? Some organisms must compete
with each other for space to live.
11. What did Francesco Redi show in his experiment?
21. Why must organisms be able to keep the conditions inside their body
constant?
12. The factor that a scientist changes in a controlled experiment is the
independent/dependent/constant variable. (Circle the right one.)
22. What is homeostasis?