Chapter 5 Review
D. no function in changing
levels
Multiple Choice
2. What characteristic has evolved that helps to
maintain homeostasis?
A. taller bodies with larger cells
B. shorter bodies with fewer cells
C. multicellular bodies with many cells
D. multicellular bodies with fewer cells
3. A system in dynamic equilibrium
makes constant changes
changes in intervals or steps
changes very infrequently
never changes at all
4. Intercellular fluid is made up mostly of
A. blood
B. water
and CO2
9. The effector for adjusting CO2 levels in the
1. Organisms undergo constant chemical
changes as they maintain an internal balance
known as
A. interdependence
B. synthesis
C. homeostasis
D. recombination
A.
B.
C.
D.
O2
C. mineral salts
D. cytoplasm
5. Intercellular fluid is important for the ex-
change of materials between
A. body cells and arteries
B. body cells and veins
C. veins and capillaries
D. body cells and capillaries
body is the
A. brain
B. spine
C. capillaries
D. chest muscles
10. One change in the body results in another
change. This second change reverses the first
change in order to maintain homeostasis.
This sequence describes a type of
A. control mechanism
B. feedback controller
C. feedback mechanism
D. effector mechanism
11. Why might a blood clot be important to
maintaining homeostasis?
A. It slows the flow of blood through the
body.
B. It prevents the loss of blood from the
body.
C. It increases the amount of water in the
blood.
D. It adds more cells to the blood supply.
Base your WJS1ver to question
the graph be lm\'.
s::J
"-
12 on the data in
o
38
Q)
137~~~~~~~~~~]~~~g:o~:asis
E
--
~
6. As a result of exercise, CO2 levels increase in
the
A.
B.
C.
D.
o
co
blood only
intercellular fluid only
blood and intercellular fluid
muscles only
7. The brain sends a signal to increase the
breathing rate when the CO2 level has
A. not changed for a while
B. decreased too much
C. increased too much
D. increased, then decreased
8. The increased breathing rate signaled by the
brain serves
A. to increase the CO2 level in the body
B. to decrease the CO2 level in the body
C. to decrease the O2 level in the body
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Preparing for the New Jersey Biology EOC Test
o
12
Time
24
(hours)
12. The graph shows evidence of disease in the
human body. A disruption in the dynamic
equilibrium is indicated by the temperature
change that occurs between points
C. C and D
A. A and B
B. Band C
D. E and F
13. Which homeostatic adjustment would the
human body make in response to an increase
in environmental temperatures?
A. a decrease in glucose levels
B. an increase in perspiration
C. a decrease in fat storage
D. an increase in urine production
14. Chemical reactions within a cell usually take
place
A. over extremely long periods of time
B. in a series of small steps
C. all at once in a single burst
D. over a period of several days
15. When a person's brain sends signals to the
chest to increase the breathing rate after
heavy exercise, it is an example of the body
A. regulating its internal water balance
B. maintaining a dynamic equilibrium
C. disrupting its own homeostasis
D. increasing enzyme reaction rates
Base your answer to question 16 on the figure
below, which represents a view of the underside
(lower surface) of a leaf
18. One reason (besides size differences) that
each plant loses a different amount of water
than the other plants is that each has
A. its particular guard cells that are adapted
to maintain homeostasis
B. the same number of chloroplasts but different rates of photosynthesis
C. different types of insulin-secreting cells
that regulate water levels
D. the same rate of photosynthesis but different numbers of chloroplasts
19. The endocrine system maintains homeostasis
by
A.
B.
C.
D.
regulating physical coordination
controlling the size of blood vessels
sending nerve impulses to the brain
releasing hormones into the blood
20. Hormones carry out their work by
A. replacing the nucleus of a cell
B. breaking down the membrane of a cell
C. binding to receptor proteins in a cell's
membrane or cytoplasm
D. changing the shape of a cell and then becoming part of the cell
21. The endocrine system differs from the nerv16. What is one main function of the stomata and
guard
A. to
B. to
C. to
D. to
cells?
store food for the cold season
help control the loss of water
undergo mitotic cell division
give support to the leaf's veins
17. The changing shape of a leaf's guard cells
helps to
A. allow the plant to grow stronger
B. prevent the plant from losing sap
C. regulate the temperature of the plant
D. maintain the plant's water balance
Base your answer to question 18 on the table
below, which shows the rate of water loss in three
different plants.
Liters of Water Lost Per Day
Cactus
0.02
Potato plant
1.00
Apple tree
19.00
ous system in that the endocrine system
A. produces faster, short-term changes
B. produces slower, long-term changes
C. operates in isolated regions of the body
D. produces changes in the brain only
22. Hormones and secretions of the nervous sys-
tem are chemical messengers that
A. store genetic information
B. extract energy from nutrients
C. carry out the circulation of materials
D. coordinate system interactions
23. Which of the following statements is true?
A. Hormones
system.
B. Hormones
system.
C. Hormones
amounts.
D. Hormones
amounts.
are carried by the respiratory
are produced by the nervous
are usually needed in small
are usually needed in large
24. The body does not produce too much of most
hormones because
A. the excretory system controls the amount
released
Chapter
51
Homeostasis and Enzymes
71
B. feedback mechanisms control the amount
released
C. cells can store any excess hormones they
receIve
D. the body can produce only fixed amounts
of each hormone
25. Which statement describes a feedback mechanism involving the human pancreas?
A. The production of estrogen stimulates the
formation of gametes for sexual
reproduction.
B. The level of sugar in the blood is affected
by the amount of insulin in the blood.
C. The level of oxygen in the blood is related to heart rate.
D. The production of urine allows for excretion of cell waste.
26. The pancreas produces one hormone that
lowers blood sugar level and another that increases blood sugar level. The interaction of
these two hormones most directly helps humans to
A. maintain a balanced internal environment
B. dispose of wastes formed in other body
organs
C. digest needed substances for other body
organs
D. increase the rate of cellular
communication
27. What process is represented by the boxed sequence below?
of starch
Ingestion
sugar
Hblood
Elevated
levels
Secretion
of Insulin
increased
Drop in
blood sugar
levels
Secretion
of Insulin
decreased
A. a feedback mechanism in multicellular
orgamsms
B. the differentiation of organic molecules
C. an immune response by cells of the
pancreas
D. the disruption of cellular communication
28. A hormone causes specific changes in a body
when it
A. delivers chemicals to nerve cells
B. makes the body's fluids more
acidic
C. arrives at its special target cells
D. attacks
invading harmful
..
mIcroorgamsms
72
Preparing for the New Jersey Biology EOC Test
29. To carry out its chemical reactions, each cell
contains
A. one specific type of enzyme for the cell
B. fewer than twenty different enzymes
C. thousands of different kinds of enzymes
D. thousands of copies of the same enzyme
30. How do chemical reactions occur at the relatively low temperature found within cells?
A. Some energy is destroyed before it heats
up the cell.
E. Some energy is stored temporarily in ATP
molecules.
C. Enzymes are used to slow (decrease) the
rate of reactions.
D. Enzymes are used to speed (increase) the
rate of reactions.
31. Two conditions that must be kept constant in
a cell in order for enzymes to work properly
are the
A. pH level and oxygen content
B. surface area and temperature
C. temperature and pH levels
D. cell volume and pressure
32. The equation below represents a chemical reaction that occurs in humans. To support the
hypothesis that enzyme C works best in a
slightly basic environment, data should be
collected about the
ENZYMEC
Substance X + Substance Y ,.,..".,,,.,,.",jl> Substance W
A. amino acid sequence of enzyme C
B. shapes of molecules X and Yafter the reaction occurs
C. amount of substance W produced at various pH levels
D. temperature of enzyme C before and after
the reaction
Base your answer to question 33 on the diagrams
belovv, which show an enzyme and four different
molecules.
Enzyme
o
Molecules:
(A)
(B)
(C)
(D)
~.3. The enzyme would most likely affect reactions that involve
A. molecule A only
B. molecule Conly
e. molecules Band D
D. molecules A and C
3-1.
Which statement best describes the interaction between an enzyme and another
substance?
A. a temporary association in which the substance changes
B. a temporary association in which the enzyme changes
e. the final product in a series of slow chemical reactions
D. the pocket into which the enzyme and the
substance fit
Analysis and Open Ended
~5. How does being multicellular increase an organism's ability to maintain homeostasis and
survive?
36. Write a brief paragraph comparing the life of
a cell in your body with that of an ameba in
the soil. Why is it more likely that the body
cell will survive for a long time, but the
ameba will not?
To survive, an organism must maintain the health
of its cells. The normal internal environment of a
human's cells would include a temperature of
37°e, a pH of 7, and a water/salt balance of 0.1
percent.
38. Which of the cells shown above would belong to someone who is not maintaining
homeostasis?
39. List, and briefly describe the roles of, the
three main parts of a feedback mechanism.
40. Use the diagram below to explain how feedback mechanisms help maintain homeostasis.
~
U
tdt.
I~/~~
Glu~ose
Bloodstream
t
Glulose
Glu~ose
•
41. Briefly explain the way our bodies adjust
breathing rates in order to maintain
homeostasis.
Stud)' the follo}ving graph to answer questions 42
and 43.
40
:Jeferto the diagram below to ans}ver question 37.
Lymph
Internal
U
Red blood cells
'2.-35
~
::J
-
I
ro
a;
0-
E 30
~
25
20
30
40
Environmental Temperature ee)
Lymph
vessel
37. Use your knowledge of biology and the diagram to explain why intercellular fluid (reF)
is so important for homeostasis.
3ase your answer to question 38 on the
;7formation and diagrams belm!:
A
B
c
D
42. The graph shows the effect of external (environmental) temperatures on a student's skin
and internal temperatures. Which statement
best describes what happens as the environmental temperature increases?
A. The skin temperature increases, then decreases to 20°C.
B. The internal temperature increases
abruptly to about 30°C.
e. The skin temperature decreases, due to
sweating, to 30°C.
D. The skin temperature increases, then levels off at about 36°C.
Chapter 5! Homeostasis and Enzymes
73
43. What is the difference between the effects of
rising external temperatures on the student's
internal temperature and skin temperature?
Explain how homeostasis is responsible for
the effects seen in the graph.
Base )'our ans.vers to questions 48 and 49 on the
diagram beloH~which represents an enzyme and
four t)pes of molecules present within a solution
in afiask.
Molecules
Enzyme
44. In desert environments, organisms that cannot maintain a constant internal body temperature, such as snakes and lizards, rarely go
out during the hottest daylight hours. Instead,
they stay in the shade, under rocks, or in burrows. Explain how this behavior helps these
organisms maintain homeostasis.
D
o
A
B
c
D
48. Which molecule would most likely react with
the enzyme? Why?
45. Describe how plants maintain their water balance. Your answer should include: (a) the
structure that plants have to perform this
function; and (b) how this structure works to
maintain water balance.
49. What would most likely happen to the rate of
reaction if the temperature of the solution in
the flask were increased gradually from 10°C
to 30°C?
46. In what way are the functions of the contractile vacuoles of an ameba and the guard cells
of a plant similar?
50. Enzyme molecules are affected by changes in
conditions within organisms. Explain how a
long-term, extremely high body temperature
during an illness could be fatal to a human.
47. Identify the four main organ systems that are
involved in maintaining homeostasis. Briefly
describe each of their roles in this process.
51. Briefly explain why it is important for the
cells of our bodies to maintain a neutral pH.
Reading Comprehension
Base your answers to questions 52 to 55 on the information belm\' and on your knowledge of biology.
Use one or more complete sentences to anSH'er each question.
I
In 2002, flight engineers Carl Walz and Dan Bursch set the record for the longest
United States space flight, with 196 days in space as members of Expedition 4 on the
International Space Station (ISS). Typically, ISS crews have six or seven members
who live on the station for 3 to 6 months. The crews live in a world of weightlessness-the station has no up or down, so there are no real ceilings or floors. While the
total inside space of the station is about equal to that of a jumbo jet, the individual
spaces in which the astronauts actually live and work are relatively small, each about
the size of a school bus's interior. Crews sleep standing up or camping out where they
feel comfortable by attaching their sleep restraints to the wall with Velcro.
Biomedical researchers are interested in studying the effects of weightlessness
on humans. Being "weightless" is a brand-new challenge never experienced before
in the millions of years humans have lived on Earth. And yet, time and again, space
travel has demonstrated the marvelous, and often subtle, abilities of the human body
to adapt. The body's reactions to weightlessness are teaching us a great deal about
its normal responses to gravity. Astronauts report that when they grab the wall of a
spacecraft and move their bodies back and forth, they feel as if they are staying in
one place and that the spacecraft is moving. Being free of gravity's effects makes us
aware of new things. Humans have evolved many automatic reactions to deal with
,
74
Preparing for the New Jersey Biology EOC Test
the constant pressure of living in a downward-pulling world. Until we leave that
world, we are usually not aware of such reactions.
These reactions include the use of signals fr.om our eyes, from the fluid-filled
bes in.our ears, fr.ompressure recept.ors on the b.ottom of our feet, and from the distribution ofliquids in .ourblo.od vessels. A sophisticated control system has evolved
t.okeep gravity from pulling all the liquid in our body t.o.ourlegs. Within minutes .of
being in a weightless envir.onment, the veins in an astr.onaut's neck begin t.o bulge.
e astronaut's face begins t.o fill out and became puffy. In this situation, the fluids
n. an astronaut's body are n.ot being pulled dawn by gravity. The fluids spread
hroughout the body. Because the b.ody seeks t.omaintain home.ostasis, this new dis.tributionoffluid causes other changes in the body in order t.ocontr.ol fluid m.ovement.
Included in these are changes in hormone levels, kidney function, and red bl.ood cell
production.
Keeping body systems stable, even when external c.onditi.ons change-that is,
aintaining a dynamic equilibrium-is as necessary for life in space as it is on Earth.
he unexpected result of "living" in space is a better understanding of how the
body works back here on Earth.
52.
Describe three ways in which life on the ISS is very different from everyday life on Earth.
53. Why are the effects of weightlessness on humans of interest to researchers?
54. How do the body's responses to weightlessness help explain homeostasis?
55. Describe some adaptations of the body related to living in a w.orld with gravity.
Chapter 5/Homeostasis
and Enzymes
75