Homeostasis practice test
Multi-choice
1
a
b
c
d
Which of the following is the correct order:
stimulus  response  coordinating centre  receptor  effector
stimulus  receptor  coordinating centre  response effector
receptor  stimulus  coordinating centre  response  effector
stimulus  receptor  coordinating centre  effector  response
2
a
b
c
d
If a response reduces a stimulus this is an example of
negative feedback
positive feedback
homeostasis
temperature control
3
a
b
c
d
Animal cells placed in a strong salt solution are likely to
shrivel through loss of water
become turgid and burst
remove salt by endocytosis
absorb water through osmosis
4
Which of the following lists contains a physiological adaptation principally associated with reducing
heat loss?
small ears and short legs
long, thick hair covering the body
an increase in metabolic rate
reduced blood flow to the skin
a
b
c
d
5
a
b
c
d
An ectothermic animal may be able to maintain its internal body temperature within reasonable limits
by
vasoconstriction and vasodilation of blood vessels close to its skin surface
raising and lowering its hair follicles
reducing or increasing its rate of metabolism
moving in or out of a warmer part of its environment
6
a
b
c
d
A structural feature that some reptiles have to help absorb energy from the sun is
a long slender body
a dark colour on the upper side of the body
long legs to raise the animal above the surface of the ground
reduced appendages such as ears and nose sizes
7
a
b
c
d
On a hot, dry day a mammal would lose water in all but one of the following ways:
through evaporation from its lungs
in its faeces and urine
through evaporation from its skin
through respiration
8
The diagram shows the transverse section through two plant structures.
Which label shows the plant tissue that transports water and minerals in the plant?
a
1
b
2
c
3
d
4
9
a
b
c
d
A terrestrial plant may control its water loss by
reducing its rate of photosynthesis
absorbing water through its root hair cells
changing the aperture of its stomata
reducing its stomatal guard cells
10
Halophytes are able to tolerate high salt levels in the soil whereas other plants cannot. This is
generally because non-halophytes
tend to take up the salt which is toxic to them whereas all halophytes exclude the salt
cannot absorb water from saline soil whereas halophytes can absorb water
dehydrate because more water leaves the plant than enters by osmosis whereas halophytes have
mechanisms to absorb more water than they lost to the soil
have roots which grow just under the surface of the soil which is usually more heavily contaminated
with salt
a
b
c
d
11
a
b
c
d
Which of the following temperature regulation systems does not assist cooling in plants?
Leaves with a large surface area
positioning of stomata towards the ground
evaporation of water from plants
closing of stomata in the hottest part of the day
The four statements below relate to questions 12-15. Read each statement carefully before answering the
questions.
A
B
C
D
12
a
b
c
d
Burrowing into the soil and seeking refuge there during the hottest months of the year.
The capacity to produce extremely concentrated urine while maintaining a normal amount of water in
the body fluids.
A small surface area to volume ratio as a result of small appendages, small ears and a larger than
normal body size.
A special organelle in a single-celled animal which collects water from the animal’s cytoplasm and
periodically contracts to expel the water into the surroundings.
Which statement refers to a behavioural adaptation?
A
B
C
D
13
a
b
c
d
Which statement refers to an adaptation/s possessed by an animal which probably lives in a cold
environment?
A
B
C
D
14
a
b
c
d
Which physiological adaptation is likely to be possessed by a small desert dwelling animal?
A
B
C
D
15
a
b
c
d
The adaptation which allows an organism to live in a freshwater lake is?
A
B
C
D
Short answer
16
When the hypothalamus of a mammal detects a rise in the body’s blood temperature, it sends out
nerve impulses which cause the vasodilation of blood vessels close to the skin. This vasodilation
results in more blood flowing close to the surface of the skin and consequently a greater loss of heat
from the body by radiation and conduction to the atmosphere.
a
In the above discussion, what is the:
i
receptor?
____________________________________
(1 mark)
ii
effector?
_____________________________________
(1 mark)
iii
stimulus?
_____________________________________
(1 mark)
iv
response?
_____________________________________
(1 mark)
b
Why is this called a negative feedback system?
(1 mark)
_____________________________________________________________________________________
_____________________________________________________________________________________
c
In this example, where is the co-ordinating centre and what does it do?
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
d
Draw the stimulus response model.
(2 marks)
17
Endotherms are animals that maintain a constant body temperature independent of the environment.
a
Explain why an animal such as a mouse has a higher metabolic rate than a donkey when both
animals live in a cool temperate environment.
(4 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
b
Marsupials such as wombats which live on the Australian mainland are smaller in general than their
counter-parts that live in Tasmania. What advantage would their greater size give to the Tasmanian
wombats?
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
c
The hypothalamus detects changes in the internal temperature of endotherms.
Discuss two responses which occur in endotherms when the hypothalamus detects a:
i
rise in body temperature.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
ii
fall in body temperature.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
d
The following diagram shows how the temperature varies along the length of an artery and a nearby
vein which carry blood to and from the foot of an Antarctic bird which is standing on ice.
i
What is the exchange of heat between the artery and vein called?
(1 mark)
_____________________________________________________________________________________
ii
Of what advantage to the bird is there in having the artery and the vein so close to one
another in the leg?
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
iii
What category of adaptation is this an example of?
(1 mark)
_____________________________________________________________________________________
18
a
Describe and explain one adaptation that a terrestrial plant may have to:
reduce heat absorption in a hot dry environment.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
b
reduce water loss on a hot, dry day.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
c
increase water absorption in a hot, dry environment.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
d
remove salt from its cells in high saline soil conditions.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
e
remove salt filled leaves in high saline soil conditions.
(2 marks)
_____________________________________________________________________________________
_____________________________________________________________________________________
19
To compare the three nitrogenous wastes, complete the table below.
Nitrogenous waste
Ammonia
Advantages
Disadvantages
(9 marks)
Animal examples
Urea
Uric acid
Extended response
What is meant by ‘homeostasis’ in living organisms? Explain how an organism’s survival depends of its
ability to respond to changes in its external and internal environments. Use the negative feedback model to
illustrate your answer.