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Worksheets

Unit 3 Exam Review

Total questions: 154

Worksheet time: 2hrs 1mins

Name
Class
Date
1.

Loops that cause a response to build up and build up until something big happens are called ____________ loops

a)

positive

b)

negative

2.

The heater kicks on and the house warms up, so it kicks off. Then the house cools a bit and the heater kicks back on. This continues all day. It's a _____________ loop.

a)

positive

b)

negative

3.

Most of the body's feedback loops are ____________ loops.

a)

positive

b)

negative

4.

Body temperature regulation is an example of a ______________ loop

a)

positive

b)

negative

5.
If the environment gets cold, we will often shiver in order to:
a)
keep body temperature the same as the external temperature
b)
decrease body temperature
c)
increase body temperature
d)
regulate blood pressure
6.
Negative Feedback Loops:
a)
amplify processes
b)
prevent small changes from getting larger
c)
are initiated during childbirth
d)
are found only in plants
7.
Maintaining body temperature is an example of a:
a)
negative feedback loop
b)
positive feedback loop
8.

In a positive feedback loop, each action creates a consequence that _____________________ the other action.

a)

decreases

b)

has no effect on

c)

amplifies

9.

In a negative feedback loop, each action creates a consequence that _____________________ the other action.

a)

decreases

b)

has no effect on

c)

amplifies

10.

A ________________ feedback loop makes a system more stable.

a)

Positive

b)

Neutral

c)

Negative

d)

Circular

11.

A _________________ feedback loop moves a system to an extreme.

a)

Positive

b)

Neutral

c)

Circular

d)

Negative

12.

A thermostat in a central heating system can determine the temperature of your living room. It switches the air conditioner on when the temperature increases to a predetermined level and shuts it off when it cools to another level. The room temperature remains within a comfortable level regardless of the temperature outside.

a)

Positive Feedback Loop

b)

Negative Feedback Loop

13.

In an economic recession, job loss leads to decreased spending, which harms businesses and leads to even more job loss.

a)

Positive

b)

Negative

14.

When the population of deer in an area begin to grow, they start overgrazing the vegetation that feeds them. When there is not enough vegetation to sustain the rapidly growing deer population, they will begin to die off until the vegetation grows back to normal levels and the deer will have enough food to repopulate again. 

a)

Positive

b)

Negative

15.

This image is an example of

a)

Equilibrium

b)

Negative

c)

Positive

d)

Temperture

16.

A organization posts an advertisement with a very "click-baity" title and image on a social media platform. The title and image draw in people to click on the ad. As the ad receives more views, the algorithm shows the ad to more people.

a)

Positive Feedback Loop

b)

Negative Feedback Loop

17.

In some developing countries poverty causes illness and contributes to poor standards of education. In the absence of knowledge of family planning methods and hygiene, this contributes to population growth and illness, adding further to the causes of poverty; “a vicious circle of poverty.”

a)

Positive Feedback Loop

b)

Negative Feedback Loop

18.

Does the graph show positive or negative feedback?

a)

Positive, because when the red line shifts, the blue one does also

b)

Negative, because the blue line starts below equilibrium

c)

Negative, because the two actions are keeping each other near equilibrium

d)

Both positive and negative because the graph moves up and down

19.

Negative feedback loops result in stabilization of a system.

Negative feedback is a process that _______ the effects of a change.

a)

reduces

b)

amplifies

c)

has no effect

20.

Positive feedback loops result in a system moving towards an extreme. Positive feedback is a process that _______ the effects of a change.

a)

reduces

b)

amplifies

c)

has no effect

21.

What is the name of the macromolecule that makes up the majority of the cell membrane?

a)

Lipid

b)

Carbohydrate

c)

Nucleic acid

d)

Protein

22.

Which statement best describes the role cholesterol plays in the membrane?

a)

It clogs the membrane

b)

It increases membrane fluidity

c)

It decreases membrane fluidity

d)

It holds the membrane together

23.

The lipid bilayer is ____ thick.

a)

1

b)

2

c)

3

d)

4

24.

The primary component of the cell membrane is the group of lipids called

a)

prostaglandins

b)

cholesterol

c)

phospholipids

d)

carbohydrate

25.

"water loving"

a)

Hydroloric

b)

Hydroelectric

c)

Hydrophilic

d)

Hydrophobic

26.

"water fearing"

a)

Hydroloric

b)

Hydroelectric

c)

Hydrophilic

d)

Hydrophobic

27.

Describes the arrangement of the cell membrane as bendable and made of many parts.

a)

the fluid mosaic model

b)

the major mobility model

c)

the crazy cell model

d)

the cell theroy model

28.

Controls the passage of materials inside and outside of the cell

a)

Cell Membrane

b)

Cytoplasm

c)

Cell Wall

d)

Endoplasmic reticulum

29.

Which term describes the relatively constant internal physical conditions of an organism?

a)

permeability

b)

homeostasis

c)

specialization

d)

unicellularity

30.

Which of the following molecules pass easily through the cell membrane, requiring little extra help or energy? Select all that apply.

a)

glucose

b)

oxygen

c)

carbon dioxide

d)

sodium

31.

The ability to allow only certain molecules into or out of the cell.

a)

permeability

b)

impermability

c)

unpermeability

d)

semipermeablity

32.

Which of the following are embedded in the phospholipid bilayer and help substances pass through?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

33.

Which of the following are embedded in the phospholipid bilayer to signal between cells?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

34.

Which of the following are embedded in the phospholipid bilayer to support the structure?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

35.

What is the name of the macromolecule that makes up the majority of the cell membrane?

a)

Lipid

b)

Carbohydrate

c)

Nucleic acid

d)

Protein

36.

Which statement best describes the role cholesterol plays in the membrane?

a)

It clogs the membrane

b)

It increases membrane fluidity

c)

It decreases membrane fluidity

d)

It holds the membrane together

37.

The lipid bilayer is ____ thick.

a)

1

b)

2

c)

3

d)

4

38.

The primary component of the cell membrane is the group of lipids called

a)

prostaglandins

b)

cholesterol

c)

phospholipids

d)

carbohydrate

39.

"water loving"

a)

Hydroloric

b)

Hydroelectric

c)

Hydrophilic

d)

Hydrophobic

40.

"water fearing"

a)

Hydroloric

b)

Hydroelectric

c)

Hydrophilic

d)

Hydrophobic

41.

Describes the arrangement of the cell membrane as bendable and made of many parts.

a)

the fluid mosaic model

b)

the major mobility model

c)

the crazy cell model

d)

the cell theroy model

42.

Controls the passage of materials inside and outside of the cell

a)

Cell Membrane

b)

Cytoplasm

c)

Cell Wall

d)

Endoplasmic reticulum

43.

Which term describes the relatively constant internal physical conditions of an organism?

a)

permeability

b)

homeostasis

c)

specialization

d)

unicellularity

44.

Which of the following molecules pass easily through the cell membrane, requiring little extra help or energy? Select all that apply.

a)

glucose

b)

oxygen

c)

carbon dioxide

d)

sodium

45.

The ability to allow only certain molecules into or out of the cell.

a)

permeability

b)

impermability

c)

unpermeability

d)

semipermeablity

46.

Which of the following are embedded in the phospholipid bilayer and help substances pass through?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

47.

Which of the following are embedded in the phospholipid bilayer to signal between cells?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

48.

Which of the following are embedded in the phospholipid bilayer to support the structure?

a)

cholesterol

b)

lipids

c)

proteins

d)

carbohydrates

49.
When you breathe, your lungs take in ___ and remove ___. 
a)
air/oxygen
b)
oxygen/carbon dioxide 
c)
carbon dioxide/waste 
d)
waste/air 
50.
The air sacs that are covered with capillaries where gas exchange takes place
a)
bronchi
b)
lungs
c)
oxygen
d)
alveoli
51.

Flap of tissue that covers the opening to the windpipe during swallowing

a)

Pharynx

b)

Trachea

c)

Epiglottis

52.
What is the main function of the respiratory system?
a)
to provide oxygen and remove carbon dioxide from the body
b)
to bring oxygen to the body
c)
to break down food and absorb nutrients
d)
to remove oxygen from the body and deliver carbon dioxide
53.
Given the following structures:
1. larynx
2. nasal cavity
3. pharynx
4. trachea
Which of the following is the correct order that air would flow during inhalation. 
a)
1,2,3,4
b)
2,3,1,4
c)
2,1,3,4
d)
4,2,3,1 
54.
Which body function is made possible by the fibrous bands stretched across the larynx?
a)
swallowing
b)
breathing
c)
diffusion
d)
speech
55.
The left lung has three lobes and the right lung has two. 
a)
True
b)
False
56.
A chamber behind the nose and mouth that leads to the trachea
a)
pharynx
b)
trachea
c)
epiglottis
d)
larynx
57.

The drawing in of breath; inhalation.

a)

Inspiration

b)

Expiration

58.

Breathing out; exhalation of breath.

a)

Inspiration

b)

Expiration

59.

What is the site of gas exchange?

a)

alveoli

b)

nose

c)

lung

d)

bronchi

60.

A cavity within a bone or other tissue, especially one in the bones of the face or skull connecting with the nasal cavities.

a)

Sinus

b)

Nose

c)

Pharynx

d)

Larynx

61.

The process of diffusing oxygen from the blood, into the interstitial fluid and into the cells.

a)

inspiration

b)

expiration

c)

internal respiration

d)

external respiration

62.

The process of exchanging oxygen and carbon dioxide in the lungs.

a)

inspiration

b)

expiration

c)

internal respiration

d)

external respiration

63.

The only externally visible part of the respiratory system

a)

Eyes

b)

Nose

c)

Pharynx

d)

Larynx

64.

Which lung has 2 lobes?

a)

Right

b)

Left

65.

The division of the trachea forms

a)

nose

b)

main bronchi

c)

lungs

d)

alveoli

66.

The opening between vocal cords

a)

glottis

b)

epiglottis

67.

Olfactory receptors are located in the mucosa of the nose. What are these receptors used for?

a)

sight

b)

smell

c)

touch

d)

taste

68.

Which part of the Respiratory System plays a major role in speech?

a)

nose

b)

pharynx

c)

larynx

d)

trachea

69.

After drinking too much water and having the stimulation or urge to use the restroom is an example of which two systems interacting with each other?

a)

Digestive and Circulatory

b)

Excretory and Circulatory

c)

Digestive and Nervous

d)

Respiratory and Nervous

70.

Wastes being removed from the blood is an example of which two systems interacting with each other?

a)

Excretory and Circulatory

b)

Excretory and Respiratory

c)

Digestive and Circulatory

d)

Digestive and Excretory

71.

Which two systems are involved in homeostasis after wastes are removed?

a)

Digestive and Respiratory

b)

Digestive and Excretory

c)

Excretory and Circulatory

d)

Nervous and Digestive

72.

Why must wastes be removed from the body?

a)

So the body can transport nutrients through the body

b)

So the body can break down nutrients

c)

So the body can stay healthy and maintain homeostasis

d)

Wastes do not have to be removed from the body

73.

Which two systems interact to break down food and transport nutrients throughout the body?

a)

Digestive and circulatory

b)

Digestive and excretory

c)

Nervous and excretory

d)

Digestive and respiratory

74.

The function of kidneys...

a)

Transport nutrients

b)

Circulate blood

c)

Break down food

d)

Waste removal

75.

This system absorbs the nutrients from the food we eat and can help to remove the wastes from the body.

a)

Excretory

b)

Digestive

c)

Immune

d)

Circulatory

76.
The respiratory system is the body system in which _______ exchange takes place.
a)
blood
b)
gas
c)
nutrients
d)
waste
77.
Which is the correct pathway that blood takes as it leaves the heart, circulates throughout the body, and returns to the heart?
a)
arterioles, arteries, venules, veins, capillaries
b)
veins, venules, capillaries, arteries, arterioles
c)
arterioles, arteries, capillaries, veins, venules
d)
arteries, arterioles, capillaries, venules, veins
78.
This is an image of the alveoli in the lungs.
a)
True
b)
False
79.
The function of the respiratory systems is to bring carbon dioxide into the body and to expel oxygen and water vapor.
a)
True
b)
False
80.
Which is the correct pathway of air into the respiratory system?
a)
nose and mouth, pharynx, trachea, bronchi, bronchioles, alveoli
b)
nose and mouth, bronchi, trachea, pharynx, bronchioles, alveoli
c)
alveoli, bronchioles, bronchi, trachea, pharynx, nose and mouth
d)
pharynx, nose and mouth, bronchioles, bronchi, trachea, alveoli
81.
The diaphragm is a dome-shaped muscle at the base of the rib cage.
a)
False
b)
True
82.
The heart is a muscular pump, about the size of your ______, that keeps the blood moving to every part of the body.
a)
foot
b)
fist
c)
face
d)
finger
83.
In which structure of the respiratory system does gas exchange take place?
a)
trachea
b)
bronchioles
c)
pharynx
d)
alveoli
84.
The largest structures in your heart are the two chambers.
a)
False
b)
True
85.
Which is the correct sequence of blood flow through the heart and lungs?
a)
left ventricle, left atrium, lungs, right ventricle, right atrium
b)
right atrium, right ventricle, lungs, left atrium left ventricle
c)
lungs, right atrium, right ventricle, left atrium, left ventricle
d)
right atrium, right ventricle, left atrium, left ventricle, lungs
86.
What is the function of this  system?
a)
Take in oxygen and release carbon dioxide
b)
Break apart nutrients into usable pieces of energy
c)
Transport nutrients and oxygen to the  body
d)
Provide movement for the body
87.
The System that contains blood vessels and the heart is the...
a)
circulatory system
b)
respiratory system
c)
digestive system
d)
Integumentary System
88.
What are the main organs of gas exchange in the respiratory system?
a)
diapragm
b)
lungs
c)
trachea
d)
bronchi
89.
When you breathe, your lungs take in ___ and remove ___. 
a)
air/oxygen
b)
oxygen/carbon dioxide 
c)
carbon dioxide/waste 
d)
waste/air 
90.
What is the main function of the respiratory system?
a)
to provide oxygen and remove carbon dioxide from the body
b)
to bring oxygen to the body
c)
to break down food and absorb nutrients
d)
to remove oxygen from the body and deliver carbon dioxide
91.
Which systems transports blood throughout the body?
a)
Respiratory
b)
Immune
c)
Circulatory
d)
Cardiovascular
92.
Which system with the heart, arteries and veins apart of?
a)
Cardiovascular 
b)
Circulatory
c)
Respiratory
d)
Immune
93.
Identify this  system.
a)
Lungs
b)
Circulatory System
c)
Artery 
d)
Respiratory System
94.
The ____________________ is the body system that transports oxygen, food, and waste through the body.  
a)
respiratory system 
b)
muscular System
c)
circulatory system 
d)
skeletal system
95.
The ____________ is a muscular organ that pumps blood to the body through blood vessels. 
a)
vein 
b)
artery 
c)
heart
96.
Which illustration of transport across the membrane requires energy?
a)
A
b)
B
c)
C
d)
D
97.
Which form of transport is being shown in the diagram.
a)
diffusion
b)
osmosis
c)
facilitated diffusion
d)
active transport
98.
Cells use energy to move materials across a membrane (low to high concentration).
a)
Active transport
b)
Passive transport
c)
Diffusion
d)
Osmosis
99.
If the sodium concentration inside a cell is greater than outside the cell, how can a cell take in more sodium?
a)
osmosis
b)
diffusion
c)
active transport
d)
passive transport
100.

When a cell forms a vesicle around unwanted particles and expels it OUT of the cell.

a)

Pinocytosis

b)

Endocytosis

c)

Receptor-mediated

d)

Exocytosis

101.
Particles are removed from a cell (pushed out).
a)
Endocytosis
b)
Exocytosis
c)
Permeable
d)
In high concentration
102.

Which type of active transport uses a vesicle to allow a large molecule to exit the cell?

a)

Endocytosis

b)

Exocytosis

103.
A type of active transport that brings particles into a cell when the cell membrane encloses a particle to make a vesicle
a)
Diffusion
b)
Passive Transport
c)
Active Transport
d)
Endocytosis
104.
In this image, the cell is using which type of molecular transport?
a)
Osmosis
b)
Diffusion 
c)
Endocytosis
d)
Exocytosis 
105.
Compare the concentrations of the sugar in the cell and the solution.  Which is HYPOTONIC?
a)
Cell
b)
Solution
106.
Facilitated diffusion is the movement of materials into and out of the cell
a)
with the use of energy
b)
with the use of proteins but no energy
c)
by moving water
d)
by using ATP
107.
The  movement of water from a high concentration to a low concentration is called
a)
diffusion
b)
osmosis
c)
facilitated diffusion
d)
active transport
108.
In this situation, where the solute is illustrated by red dots, predict if will WATER move into or out of the cell, and how that will affect the cell.
a)
Water will move into the cell and the cell will expand.
b)
Water will move into the cell and the cell will shrink.
c)
Water will move out of the cell and the cell will expand.
d)
Water will move out of the cell and the cell will shrink.
109.
Semi-permeable mean to allow
a)
all materials across the membrane
b)
only some materials across the membrane
c)
no material to cross the membrane
d)
to allow only water across the membrane
110.

Which type of active transport is displayed?

a)

Endocytosis

b)

Exocytosis

111.
Diffusion is the movement of particles
a)
from low to high concentration
b)
from  high to low concentration
c)
from equilibrium to areas of high concentration
d)
all of the above
112.
What characteristic of the cell membrane allows only certain material to pass through?
a)
selective gating
b)
selective permeability
c)
hydrophilia
d)
selective service
113.
Moving from areas of LOW concentration to areas of HIGH concentration is called?
a)
Passive Transport
b)
Active Transport
c)
Diffusion
d)
Osmosis
114.
When moving particles AGAINST their concentration gradient, this is called?
a)
Passive Transport
b)
Osmosis
c)
Active Transport
d)
Facilitated Diffusion
115.
If the question asks about Osmosis, I will look for an answer about?
a)
Particles
b)
Salt
c)
Sugar
d)
Water
116.
Which is true about active transport?
a)
It requires energy
b)
it does not require energy
c)
It moves substances down the concentration gradient
d)
it moves material from high to low concentration
117.
What are two types of passive transport?
a)
endo and exocytosis 
b)
cookies and milk
c)
active and passive 
d)
Osmosis and diffusion
118.
What does it mean that a cell membrane is semi-permeable?
a)
It allows all substances in
b)
It allows some substances in
c)
It allows nothing in
119.
Passive transport requires no
a)
concentration gradients
b)
osmosis
c)
motion
d)
energy
120.
This cell organelle helps organisms maintain homeostasis by controlling what substances may enter or leave cells.
a)
vacuole
b)
nucleus
c)
cell membrane
d)
cell wall
121.
Engulfs large molecules and moves them inside the membrane.
Uses energy.
a)
exocytosis
b)
endocytosis
c)
protein channel 
d)
diffusion
122.
Engulfing a large substance from the inside of the cell to move it outside of the cell. 
Uses energy. 
a)
exocytosis
b)
endocytosis
c)
photosynthesis
d)
diffusion
123.
Particles move from high concentrations to low concentrations.
Doesn't need energy
a)
passive transport
b)
facilitated transport
c)
active transport
d)
exocytosis
124.
Osmosis is the movement of 
a)
water from low to high concentration
b)
particles from low to high concentration
c)
water from high to low concentration
d)
particles from high to low concentration
125.
A state of biological balance
a)
homeostasis
b)
hypertonic
c)
hypotonic
d)
hippocampus
126.

Which group of organelles helps maintain homeostasis within the cell?

a)

vacuoles and mitochondrion

b)

ribosomes and cytoskeleton

c)

lysosome, vacuole, and cell membrane

d)

cell wall and rough endoplasmic reticulum

127.

What type type of transport is shown in the image?

a)

active transport because particles are moving from low concentration to high concentration

b)

passive transport because particles are moving from high concentration to low concentration

c)

active transport because particles are moving from high concentration to low concentration

d)

passive transport because particles are moving from low concentration to high concentration

128.

What type of transport is shown in the image?

a)

Active transport because particles are moving from high concentration to low concentration

b)

Active transport because particles are moving from low concentration to high concentration

c)

Passive transport because particles are moving from high concentration to low concentration

d)

Passive transport because particles are moving from low concentration to high concentration

129.

What is the difference between active and passive transport?

a)

Active is high to low; Passive is low to high

b)

Active uses no cell energy; Passive uses cell energy

c)

Passive is high to low and uses no energy; Active uses energy and is low to high

d)

Passive uses no cell energy

130.

Fill in the blank:

Osmosis is the movement of ________ across a cell membrane from high to low.

a)

Carbon dioxide

b)

Starch

c)

Water

d)

Oxygen

131.
An ISOTONIC solution has a(n) ______________ concentration of solute (dissolved stuff) than inside the cell.
a)
lower
b)
equal
c)
higher
132.
What type of solution is this cell in?
a)
Isotonic
b)
Hypertonic
c)
Hypotonic
d)
diffused
133.
The salt in the glass of saltwater is considered the
a)
solvent
b)
solution 
c)
pepper
d)
solute
134.

In an isotonic solution which way will the water flow

a)

it will not flow at all

b)

it will flow into the cell

c)

it will flow both ways at equal rates

d)

out of the cell

135.

A solution outside of a cell that contains a higher water concentration than the cytoplasm of a cell is called:

a)

solution

b)

hypertonic

c)

hypotonic

d)

isotonic

136.
In this picture, which way will the water move?
a)
Water will move into the cell
b)
Water will move out of the cell
c)
Water will move in and out of the cell
d)
Water will not move
137.
In this picture, how do you classify the solution?
a)
The solution is hypotonic
b)
The solution is hypertonic
c)
The solution is isotonic
d)
The solution is my tonic
138.

Which of the following molecules crosses through a semipermeable membrane during the process of osmosis?

a)

water

b)

salt

c)

sugar

d)

protein

139.

If the semipermeable membrane allows the green chemical to pass through it freely, where will the green chemical move?

a)

right to left

b)

left to right

c)

up and down

140.

The concentration of red molecules outside the cell is higher than the concentration inside the cell. The red molecules cannot penetrate the cell. The cell is inside a ______.

a)

hypotonic solution

b)

hypertonic solution

141.

The membrane does not allow the green molecules to pass through it. What will happen next?

a)

Water will flow into side A.

b)

Water will flow into side B.

c)

Water will stay still.

142.

Which Type of solution is the middle cell placed in?

a)

Hypertonic

b)

Hypotonic

c)

Isotonic

d)

Robotonic

143.
What type of solution allows water to enter the plant cell?
a)
hypotonic solution
b)
hypertonic solution
c)
isotonic solution
d)
active transport
144.

What would happen to a cell placed in a hypertonic solution

a)

The cell would shrink

b)

The cell would expand and possibly burst

c)

The cell would remain the same

d)

The cell would dance and do the Nay Nay!

145.
The diffusion of WATER across a semi-permeable membrane is
a)
osmosis
b)
diffusion
c)
endocytosis
d)
exocytosis
146.
How does a cell maintain homeostasis?
a)
Regulates what enters and leaves the cell
b)
Flexibility
c)
Protective barrier
d)
Structure and support
147.
A cell will _____________________ in a hypertonic solution.
a)
swell
b)
shrink
c)
will not change
d)
will explode
148.
A cell will __________________ in a hypotonic solution.
a)
swell and perhaps burst (lyse)
b)
shrink
c)
the size of the cell will not change
d)
the size of the cell will change from large to small and from small to large
149.

After examining this diagram showing the concentration of water inside and outside of the cell, identify the tonicity of the solution.

a)

hypertonic

b)

hypotonic

c)

isotonic

150.

The solution surrounding the cell in Diagram B, would be defined as:

a)

hypertonic

b)

hypotonic

c)

isotonic

151.
The cell below is in a _________ solution.
a)
Hypotonic
b)
Hypertonic
c)
Isotonic
152.
What type of solution is this cell in?
a)
Isotonic
b)
Hypertonic
c)
Hypotonic
d)
diffused
153.

Nemo and other ocean dwelling fish cannot survive in freshwater because......

a)

freshwater is hypertonic to Nemo's cells and will result in water leaving them causing the cells to shrink

b)

freshwater is hypotonic to Nemo's cells and will result in water leaving them causing the cells to shrink

c)

freshwater is hypertonic to Nemo's cells and will result in water entering them causing the cells to swell and burst

d)

freshwater is hypotonic to Nemo's cells and will result in water enter them causing the cells to swell and burst

154.
Homeostasis
a)
allows for a wildly fluctuating internal environment
b)
is impossible in vertebrates
c)

is the maintenance of a relatively stable internal environment

d)

is the maintenance of a relatively stable external environment