Answers
Practice questions:
1. Which of the following would not be classified as living:
A.
B.
C.
D.
A wheat seed
A fresh potato
A virus
A spider
2. Which of the following is not a characteristic of life:
A.
B.
C.
D.
Ability to exchange gases with the environment
Ability to manufacture glucose from carbon dioxide and water
Ability to reproduce
Ability to move
The following image relates to the next 4 questions
Organelle B
Organelle A
3. The image above was seen using what type of microscope?
A.
B.
C.
D.
Light microscope
Scanning electron microsocope
Fluoresient microscope
Transmission electron microscope
4. Organelle A is a/the:
A.
B.
C.
D.
Mitochondrion
Gogi body
Rough endoplasmic reticulum
Vacuole
5. There is likely to be a large number of this type of organelle in cells of which
organ or tissue?
A.
B.
C.
D.
Skin
Bone
lungs
Skeletal muscles
6. The function of organelle B is:
A.
B.
C.
D.
To package materials made within the cell into vesicles for transportation
To carry out aerobic respiration and thus provide ATP for cell use
To produce glucose and oxygen using light as an energy source
To transport protein produced on the ribosome’s to other parts of the cell
7. The following image of human blood cells was seen using what type of
microscope?
A.
B.
C.
D.
Light microscope
Scanning electron microscope
Fluorescent microscope
Transmission electron microscope
8. Choose the best statement about prokaryotic and eukaryotic cells
A.
B.
C.
D.
Prokaryotic cells contain no organelles
Eukaryotic cells exist only in muliticellular organisms
Prokaryotic cells are smaller that eukaryotic cells.
Eukaryotic cells contain only membrane bound organelles
9. To see plant cells with a microscope you usually need a magnification of
about
A.
B.
C.
D.
x5
xl0
xl00
x1000
10. The diagram below shows an organism that was observed as a student
looked into the ocular of a light microscope. It was viewed under x100
magnification and the diameter of the field of view is 1800m. The circular
diagram represents a complete field of view
The approximate length (not width) of the organism is:
A.
B.
C.
D.
750 m
25 m
430 m
300 m
The next two questions refer to the following diagrams
4
7
5
1
8
3
2B
6
2A
3
1
9
Cell type A
Cell type B
11. Considering the diagrams above it is true to say that:
A.
B.
C.
D.
Organelle 1 is the golgi body
Organelle 3 is the vacuole
Organelle 8 is the chloroplast
label 5 is pointing some grains of starch
12. Which of the following statements regarding either the structure or function of
each organelle is correct:
A.
B.
C.
D.
Genetic material is found within organelle 3
Organelle 9 is the site of photosynthesis
Aerobic cellular respiration takes place in organelle 8
Structure 6 is only found in eukaryotic cells
13. Composing elements common to proteins, lipids, carbohydrates and nucleic
acids include:
A.
B.
C.
D.
Carbon, and hydrogen only
Carbon and oxygen only
Carbon, hydrogen, oxygen and nitrogen only
Carbon, hydrogen and oxygen only
14. The function of protein in the human body include all of the following except:
A.
B.
C.
D.
Speeding up the rate of chemical reactions
Insulating the body to reduce heat loss
Playing a role in fighting infection by foreign agents
Forming part of the structure of hair and nails
15. Which of the following is a polymer:
A.
B.
C.
D.
DNA
Sucrose
Cholesterol
Glucose
16. The process involving the breaking of bonds by the addition of water is
called:
A.
B.
C.
D.
Hydrolysis
Condensation polymerization
Hydration
Monomerization
17. Which of the following is not a component of the cell membrane:
A.
B.
C.
D.
Phospholipid molecules
Cellulose molecules
Chlolesterol molecules
Protein molecules
The information in the box below is relevant to the following 5 questions
Outside of Cell
Inside of Cell
18.
A.
B.
C.
D.
In the image above which of the following are lipids?
A1 and A2
E and D
A2 and E
C and G
19. In the image above, which of the following are proteins?
A.
B.
C.
D.
A1 and E
C and G
A1 and B
D and E
Molecule A
20. Molecule A showed a net movement from the outside of the cell to the inside of the cell.
Based only on this information and your biological understanding you can conclude that:
A.
B.
C.
D.
Molecule A could be entering the cell by either the process of diffusion or osmosis
Molecule A could be entering the cell by osmosis only
Molecule A must be entering the cell by active transport
Molecule A could be entering the cell by exocytosis
21. If Molecule A is glucose and it enters the cell along the path shown by the arrow, you can
conclude that the process by which it enters the cell is:
A.
B.
C.
D.
Osmosis
Diffusion
Facilitated diffusion
Active uptake
22. H-I indicates the:
A.
B.
C.
D.
Phospholipid bilayer
Glycoprotein layer
Cell membrane
Hydrophilic layer
23. An example of a substance that cannot cross the phospholipid bilayer of the membrane is:
A.
B.
C.
D.
Alcohol
Oxygen
Water
Na+
24. Lipophilic substances are able to dissolve into the lipid interior of the phospholipid bilayer and
diffuse into the cell. Such substances include:
A.
B.
C.
D.
Alcohol and sodium
Ethanol and anaesthetic
Water and glucose
Potassium and nitrogen
25. Which of the following substances normally fails to cross cell membranes under any
circumstances?
A.
B.
C.
D.
Water
DNA
ethanol (ethyl alcohol)
oxygen gas
26. The cell membrane has all of the following functions except:
A.
B.
C.
D.
To control what enters and leaves the cell
To help determine self from non self
To receive incoming messages from signalling molecules
To prevent an animal cell from bursting when it is placed in distilled water
27. Cellular membranes are important because they:
A.
B.
C.
D.
Provide compartments within a cell
Stop water from leaving the cell
Enable ions to freely enter the cell
Stop the cell from bursting when placed into fresh water
28. Which of the following is necessary in order to have the special phenomenon of osmosis?
A. a permeable membrane
semipermeable membrane
B. an isotonic solution
C. protein channels
29. Pieces of potato each weighing 30 grams were placed into an unknown solution in a beaker.
Thirty minutes later they were removed and reweighed. Their average weight after removal
from the solution was 26.5 grams.
It is most likely that their weight change was due to:
A.
B.
C.
D.
a net movement of water out of the potato cells via osmosis
a net movement of solutes out the potato cells via diffusion
a net movement of water into the potato cells via osmosis
a net movement of water into the potato cells via diffusion
30. Compared to the cytoplasm of the potato cells, the solution in which the potato pieces were
place could be described as:
A.
B.
C.
D.
Isotonic
Dilute
Hypertonic
Hypotonic
31. If a cell has a solute concentration of 0.09% which of the solutions would be hypotonic to the
cell?
A.
B.
C.
D.
1% solute
0.09% solute
0.07% solute
10 % solute
The following two questions refer to the experiment outline below:
In a series of six experiments, animal cells and plant cells were placed in solutions of different
concentrations.
32. Based on the result of these experiments
A.
B.
C.
D.
The solution used in experiment 1 was isotonic
The solution used in experiment 5 was hypotonic
The solutions use in experiment 2 was hypertonic
The solutions used in experiment 6 was hypertonic
33. Which of the following experiments shows a cell that is plasmolysed?
A.
B.
C.
D.
Experiment 2
Experiment 5
Experiment 3
Experiment 4
34. Consider "Cell A" and " Cell B" below:
Cell A
Cell B
All of the following statements about these "Cells" are true EXCEPT for one. Which is
the incorrect statement?
A. Cell B has a larger surface area than cell A
B. Cell A has a smaller volume than Cell B
C. Cell A has a larger volume to surface area ratio than Cell B
D. Cell A would be supplied with oxygen by diffusion at a faster rate that Cell B
35. Which of the following cells show a specialization for the rapid absorption of materials from its
surrounding environment?
Cell X
Cell Y
A.
B.
C.
D.
X and Y
Z and X
Y and Z
X, Y and Z
36. The most important reason that cells are very tiny is:
A.
B.
C.
D.
So that they cannot be seen with the naked eye
To give them a small surface area to volume ratio,
To enable them to be quickly replaced when damaged
To enable them to very rapidly absorb their requirements and remove their wastes
Cell Z.
37. Enzymes are best described as:
A. Proteins that react with substrates
B. Nucleic acids that catalyze the breakdown of complex molecules by lowering the activation
energy required to start the reaction.
C. Proteins that increase the rate at which reactions proceed by lowering the activation energy
required
D. Molecules that build complex compounds from simpler ones.
38. Experiments were carried out to show the effects of pH and temperature on enzyme activity.
The experiments also tested the effects of a chemical called an inhibitor. The results are
shown in the graphs.
The best conclusion that can be drawn from these results is that the inhibitor affects
A. pH.
B.
temperature.
C.
enzyme activity.
D. enzyme concentration.
39. .Which of the following does NOT apply to an enzyme:
a. Catalyst
b. Inorganic
c. Protein
d. All of the above apply to an enzyme
40. When an enzyme catalyzes a reaction:
a. Substrate(s) bind in the active site
b. Products bind in the active site
c. The shape of the enzymes active site always remains exactly the same
d. The enzyme is consumed by the reaction
41. Feedback mechanisms regulate the rate of enzyme activity, effectively “turning off” an
enzyme in a reversible way until more product is needed. Which of the following would be
most effective as a feedback mechanism?
A.
B.
C.
D.
Reduced concentration of product
Increased concentration of substrate
A change in pH
Temporary binding of a non-substrate molecule in the active site
42. Lactase is an enzyme that catalyses the breakdown of lactose (a sugar found
naturally in milk) into the monosaccharides glucose and galactose. Which of the
following statements is accurate in describing the activity of the lactase enzyme?
A.
B.
C.
D.
Lactase can function equally effectively at many different pH levels
Lactase will stop working when the temperature is lower than 37 degrees Celsius
Lactase is converted to glucose and galactose by the reaction
One lactase enzyme can catalyze the breakdown of many lactose molecules
Consider the following graph
43. In the graph above which letter indicates the activation energy needed to begin an enzyme
driven reaction
A.
B.
C.
D.
a
b
c
d
44. Enzymes are molecules consisting of subunits of:
A.
B.
C.
D.
glucose
fatty acids
glycerol
amino acids
45. The compound acted upon by an enzymes is called the:
A.
B.
C.
D.
substrate
product
active site
reagent
46. Enzymes can be denatured by all of the following except:
A.
B.
C.
D.
a significant increase in temperature from the optimum temperature for the enzyme
a significant decrease in temperature from the optimum temperature for the enzyme
a significant increase in pH from the optimum pH for the enzyme
a significant decrease in pH from the optimum pH for the enzyme
OOPS. The next question appears to have no correct response ….sorry. See
comments following
The next question refers to the graph below
Enzyme X
Enzyme y
Enzyme z
47. Is it likely that all of these types of enzymes:
A. Are found in human cells (no enzymes found in human cells will function optimally
at 4 or 95 deg. Celsius!)
B. Will be denatured at temperatures exceeding 90 oC (Enzyme Z is not denatured at 95
deg Celsius for example, so this statement doesn’t apply to all three enzyme
types)
C. Have the same optimal operating temperature (optimal pH varies for each enzyme)
D. Have the same range of operating temperature (The range is broader for enzyme Y
than te others for example)
E. None of the above
Short Answer questions
A small microbe was placed on a microscope slide that had a scale grid with lines at
regular intervals of 10 μm etched into its surface. The microbe was examined with a
light microscope. The result was:
A scientific study
(i)
(ii)
(iii)
(iv)
Given the dimensions of the grid, what is the diameter of the microbe?
(1 mark) 15 um
The specimen looked very pale and washed out when viewed under the
microscope. Other than applying a stain, what could be done to improve
the contrast evident in the specimen? (1 mark) adjust the iris diaphragm to
reduce the amount of light passing through the specimen
The microbe was viewed using a x10 ocular and a x100 objective lens.
What is the total magnification use to view the microbe? (1 mark) x1000
If the student changed the objective lens to a power of x10 describe how
the image viewed would be affected. (1 mark) decreasing the
magnification gives you a wider field of view. So the microbe would
appear much smaller, you would see less detail but you would see a lot
more of the slide.
Question 2:
(i)
List the following in order of decreasing size from largest to smallest:
 Cell
 nucleus
 tissue
 ribosome
 mitochondrion
 Plant vacuole
2 marks
Largest: tissue, cell, plant vacuole, nucleus, mitochrondrion, ribosome smallest



(ii)
List the following in order from outside to inside a leaf cell:
nuclear envelope
 cytosol
cell wall
plasma membrane
 nucleolus
Outside: cell wall, plasma membrane, cytosol, nuclear envelope, nucleolus : innermost 2 marks
Question 3:
Images A and B below are both of separate transmission electron micrographs of
golgi bodies.
A
B
These images are very different to each other. Give a reason for the difference
between these images of the golgi body.
1 mark
A and B show two different cross section through the same organelle. Thus they look
different.
(A is a section vertically through the stack of membranes, and B is a section
horizontally through one membrane “disk”)
Question 4:
Complete the following table:
Biomolecule Type
Subunit(s)
carbohydrate
Monosaccharide or
glucose
protein
Amino acids
lipid
Glycerol and fatty acids
Specific Example
Cellulose
Any one of
Enzyme
Hormone
Antibody
Keratin
Collagen
Actin
Myosin
Membrane protein:
receptors or carriers
Histone protein
Haemoglobin
Any one of
Phospholipid
Fat
Wax
Oil
(cholesterol and steroid
hormones are not
composed of glycerol and
fatty acids so really don’t
work in this table since the
sub unites that the example
is formed from are specified)
TOTAL 6 marks
5. The following questions relate to the image below:
Diagram A
Diagram B
X
Y
a) Name structures X and Y (2 marks)
X: Phospholipid bilayer
Y: protein channel
b) (i) Which diagram shows active uptake? B ( 1 mark)
(ii) Explain how this diagram shows active uptake? (3 marks)
The concentration of particles is higher inside the cell than outside(1)
However the particles are shown to be moving from an area of relatively low concentration(outside
the cell) to an area of higher concentration(inside the cell)(1)
This movement against their concentration gradient required the input of energy and is thus active
uptake(1)
(iii) What could you add to this illustration to represent active uptake more accurately?
(1 mark) add ATP(energy) directed at the carrier protein/protein channel
c) (i) What process is illustrated in the other diagram?(1 mark)
Facilitate diffusion
(ii) Explain your reason for choosing this process. (2 marks)
The particles are moving……… from a region of higher particle concentration to a region of lower
particle concentration(or along their concentration gradient)(thus diffusion)(1)
And are moving through protein channels/carrier proteins rather than across the phospholipid
bilayer.(thus facilitated)(1)
2.
Birds are homeothermic organisms, meaning that they maintain a core body temperature
within narrow limits. Emperor Penguins naturally inhabit Antarctic whilst Fairy Penguins do
not. In fact if Fairy Penguins were taken to Antarctic and let loose into the wild they would
soon die. Clearly and carefully suggest and explain a reason why Emperor Penguins can
survive in the Antarctic while Fairy Penguins cannot.
Emperor penguins(E.P.) are larger than fairy penguins and so have a relatively small surface area to volume
ratio (1)
Thus E.P lose heat to their environment across their body surface at a much slower rate than fairy penguins(1)
Thus E.Ps conserve heat better and could maintain their core temperature in the freezing Antarctic climate
better than fairy penguins who lose heat at a much faster rate per unit volume and would be unlikely to be
able to maintain a stable core temperature.(1)
/3marks
Question 7
The diagram below represents a chemical reaction catalysed by an enzyme.
Active site
enzyme
substrate
Enzyme/substrate
complex
Enzyme
products
Label the diagram with the words “enzyme”, “substrate”, “product”, “active site” and “enzymesubstrate complex”.
(a) How does this represent the lock-and-key or the induced fit model of enzyme action? Give reasons
to support your answer. (2 marks)
This represents the lock and key model of enzyme action since the shape of the active site is a
precise complementary fit with the substrate; consistent with the lock and key model. The
active site doesn’t show a change in shape in any of the images as it would with the induced
fit model.
(c) The enzyme amylase, which is found in saliva, promotes the breakdown of starch to maltose.
List three ways in which this reaction can be sped up, and explain why.
1. Increase temperature(1) This increases the kinetic energy of the particles and as the
enzymes and substrates are moving more quickly more frequent effective collisions occur
(1)between enzyme and substrate, speeding up the catalysis.,
2. Increase in enzyme concentration(1)
Increase no. of enzyme molecules increases chance on enzyme subustrate collisions and thus
more effective collision between substrate and active site of enzyme, increasing the speed of
catalysis.(1)
3 increase in substrate concentration up to saturation point
Increase no. of substrate molecules will initially increase reaction rate because if there are more
molecules this increases chance of enzyme subustrate collisions and thus more effective collision
between substrate and active site of enzyme, increasing the speed of catalysis. This is only up to a
saturation point after which point all active site are occupied at any moment and adding more
substrate at this point will not make the reaction happen faster.(1)
(6 marks)
A
A
l