F.4 Biology
1st Term Mock Exam
Part A: Multiple-Choice Questions (32%)
Directions: The following two questions refer to the table below, which shows the relative
abundance of different organelles in four types of cells.
Key: Number of ‘+’ indicates the relative abundance of the organelle;
‘ ’ indicates the absence of the organelle.
1.
Which cell type is most likely a liver cell?
A R
B S
C T
D U
2.
Which cell type is most likely found in the wall of a capillary?
A R
B S
C T
D U
3. All living cells
A carry out photosynthesis.
B come from pre-existing cells.
C can move.
D have a nucleus.
4. A student observed some cells under a light microscope at different magnifications.
The diagram below shows the change in the image observed.
Some steps in microscopic observations are listed below.
(1) turn the coarse adjustment knob
(2) turn the fine adjustment knob
(3) adjust the diaphragm
(4) rotate the nosepiece
(5) move the slide to the left
(6) move the slide to the right
Which of the following sequences of steps results in the change shown in the diagram?
A (1) → (3) → (4) → (5)
B (3) → (5) → (6) → (4)
C (4) → (6) → (1) → (2)
D (5) → (4) → (2) → (3)
5. Which of the following processes does not require energy?
A white blood cells engulf bacteria
B glucose is absorbed from the lumen of the small intestine into the villi
C transport of nutrients across the cell membrane against the concentration
⠀⠀⠀gradient
D oxygen enters red blood cells in the lungs
6. When the word 'box' is viewed under a microscope, which of the following can be
seen ?
A box
B pox
C xoq v
D xop
Directions: The following two questions refer to the diagram below, which shows the
appearance of a plant cell before and after immersion in a certain liquid X.
7. Liquid X is
A a hypotonic solution.
B distilled water.
C an isotonic solution.
D a hypertonic solution.
8. After immersion, space Y contains
A air.
B water.
C diluted cell sap.
D liquid X.
Directions: The following 2 questions refer to the graphs below, which show the effects of
different pH on the rate of certain enzymatic reactions:
9. Which graph illustrates that the enzyme involved is most effective in a neutral
medium ?
A W
B X
C Y
D Z
10. The presence of hydrochloric acid helps a type of enzyme in gastric juice to digest
protein. Which graph illustrates the effects of different pH on the actions of this
enzyme?
A W
B X
C Y
D Z
11. The diagram below shows a set-up to study the effect of amylase on starch. After 3
hours, the water in the beaker was heated with Benedict's solution and a red
precipitate appeared.
Which of the following can be deduced from the above experiment?
A Glucose was formed from the digestion of starch.
B Starch could not pass through the dialysis tubing.
C The dialysis tubing allowed reducing sugar to pass through.
D The water potential of the solution in the dialysis tubing increased.
12. The graph below shows the effect of the change in the external concentration of an
ion on the concentration of the ion within some plant cells:
Which of the following conclusion(s) can be drawn from the graph ?
(1)
The ion is taken up by the cells against a concentration gradient.
(2)
The uptake of the ion occurs only in living cells.
(3)
The cell membrane becomes impermeable to the ion when the
external ion concentration reaches 2 x 10-3 mol kg-1.
A (1) only
B (3) only
C (1) and (2) only
D (1) and (3) only
13. What happens when a unicellular alga is placed in a solution with a water potential
higher than its cell sap?
A The cell becomes turgid.
B The cell expands and finally bursts.
C The size of its vacuole decreases.
D The volume of its cytoplasm decreases.
Directions: Questions 14 to 16 refer to the following experiments:
Two test tubes containing 5 cm³ of hydrogen peroxide solution and 1cm³ of catalase solution
respectively were kept at 30℃ for 30 minutes. The content of the two tubes were then mixed
and maintained at the same temperature, and the amount of oxygen released was recorded for
5 minutes. The same experiment was repeated at 40℃. The results are shown in the graph
below:
14. The initial rate of oxygen production at 40℃ is higher than that at 30℃ because
A catalase is denatured at lower temperatures.
B oxygen is less soluble at higher temperatures.
C oxygen is less soluble at higher temperatures.
D the substrate molecules have more kinetic energy at higher temperatures.
15. Which of the following is a correct interpretation of the graph?
A At 30℃, the rate of reaction was highest at the 5th minute.
B At both temperatures, the amount of oxygen released in 5 minutes was the
⠀⠀⠀⠀ same.
C At both temperatures, the time for the decomposition of all hydrogen peroxide
⠀⠀⠀⠀ was the same.
D All active sites of the enzymes were occupied at the end of the experiment.
16. A third experiment was carried out as before but the contents were kept at 90℃.
Which of the following would best indicate the result of this experiment?
c
17. Which of the following sets of carbohydrates are correctly described in the table
below?
A
B
C
D
Cell wall structure
Cellulose
Starch
Sucrose
Cellulose
Storage product
Glucose
Sucrose
Starch
Starch
Transported food
Starch
Glucose
Glucose
Sucrose
18. In a starving mammal, the food reserves in the body will be depleted for energy
release according to the following sequence :
A
B
C
D
carbohydrates, fats, proteins
carbohydrates, proteins. fats
fats, carbohydrates, proteins
fats, proteins, carbohydrates
Directions: Questions 19 to 20 refer to the diagram below, which shows part of the human
digestive system:
19. Which structures produce enzymes for digesting proteins in the alimentary canal?
A 1, 2 and 4 only
B 1, 2 and 5 only
C 1, 3 and 5 only
D 2, 4 and 5 only
20. Which structures produce chemicals that facilitate lipid digestion?
A 2 and 4 only
B 2 and 5 only
C 4 and 5 only
D 2, 4 and 5 only
21. Excess amino acids absorbed into the human body will be
A Used to form bile.
B Used to form new cells
C Stored in the liver as protein.
D Converted to urea and carbohydrates.
22. Bile is a digestive juice in our body. Which of the following statements about bile is
correct?
A It is produced and stored in the gall bladder.
B It contains chemicals that digest fat.
C It is alkaline.
D It stimulates peristaltic movement of the small intestine.
23. Which of the following comparisons between the milk dentition and the permanent
dentition of humans is/are correct?
Milk dentition
Permanent dentition
(1)
Fewer molars
More molars
(2)
No canines
With canines
(3)
Serves babies whose main diet is
milk
Serves adult whose main
diet is solid food
A
B
C
D
(1) only
(3) only
(1) and (2) only
(2) and (3) only
Directions: The following two questions refer to the diagram below, which shows an
experimental set-up used to compare the composition of inhaled and exhaled air. A person
breathes slowly and deeply for 20 times through the mouthpiece.
24. What is the colour of the hydrogencarbonate indicator in the two boiling tubes at the
end of the experiment?
P
Q
A red
yellow
B purple
red
C yellow
red
D yellow
purple
25. What conclusion can be drawn from the results of this experiment?
(1)
The oxygen content in the inhaled air is higher than that in the exhaled air.
(2)
The carbon dioxide content in the exhaled air is higher than that in the inhaled
⠀⠀⠀⠀ air.
(3)
In the process of gas exchange, carbon dioxide diffuses from the capillaries
⠀⠀⠀⠀ into the air sac.
A (2) only
B (3) only
C (1) and (2) only
D (2) and (3) only
Directions: The graph below shows the change in air pressure in the lungs of a person within
a period of time.
26. Which of the following statements about the events that happen in different periods of
time are correct?
(1)
During t1, the volume of the lungs is increasing.
(2)
During t2, the intercostal muscles contract.
(3)
During t3, the diaphragm is becoming flattened.
A (1) and (2) only
B (1) and (3) only
C (2) and (3) only
D (1), (2) and (3)
27. At which of the periods is the person inhaling?
A t1 only
B t2 only
C t1 and t3 only
D t2 and t3 only
Directions: The graph below shows the change in volume of the lungs of a person within a
period of time.
28. Which of the following statements about the air pressure in the lungs at different
periods is/are correct?
(1)
At time X, the air pressure in the lungs is lower than the atmospheric pressure.
(2)
At time Y, the air pressure in the lungs is increasing.
(3)
At time Z, the air pressure in the lungs is higher than the atmospheric pressure.
A (1) only
B (3) only
C (1) and (3) only
D (2) and (3) only
Directions: The graph below shows the change in blood pressure in the pulmonary artery.
29. Which of the following correctly shows the conditions of the tricuspid valve and the
semilunar valve on the base of pulmonary artery at time X?
Tricuspid valve
Semilunar valve on the base of
pulmonary artery
A opens
opens
B opens
closed
C closed
opens
D closed
closed
Directions: The following two questions refer to the diagram below, which shows a cross
section of the human heart.
30. Which of the following valves are in contact with the oxygenated blood?
A P and R
B P and S
C Q and R
D Q and S
31. The valves that close when ventricles contract are
A P and Q.
B P and R.
C Q and S.
D R and S.
32. Which of the following correctly shows a possible route of blood flowing from the
lungs to the liver?
A pulmonary veins → left atrium → left ventricle → aorta → hepatic artery
B pulmonary veins → left atrium → left ventricle → aorta → hepatic vein
C pulmonary veins → right atrium → right ventricle → aorta → hepatic portal
⠀⠀⠀vein
D pulmonary veins → right atrium → right ventricle → aorta → hepatic artery
Part B: Structured Questions (68%)
1. For each component of blood listed in column 1, select one function listed in
column 2 and put the appropriate letter in the space provided. (4 marks)
Column 1
2.
Column 2
a
Red blood cells
___
A
Involved in blood clotting
b
White blood cells
___
B
Some of them produce
antibodies
c
Blood platelets
___
C
Transports antibodies and
hydrogencarbonate ions
d
Plasma
___
D
Carry oxygen
The photomicrograph below shows some Zebrina epidermal cells.
a
Name structures W, X, Y and Z.
(2 marks)
b
Name the major polysaccharide of which structure W is made.
(1 mark)
c
State one function of structure W.
(1 mark)
d
Compare the permeability of structures W and Z.
(1 mark)
e
If the magnification of the eyepiece is 10X, what is the magnification of the
objective in giving the above photomicrograph? Show your calculation.
(1 mark)
3.
In the space provided below, suggest one change in the diet to alleviate each of the
health problems and explain your answers. (6 marks)
Anaemia
Constipation
Obesity
4. Tracy has frequent diarrhoea (watery faeces) and is diagnosed with coeliac disease.
Her doctor told her that she lacked the enzyme for digesting gluten, a protein found in
wheat, but she could digest proteins in meat using other proteases produced in her
body. She was advised not to eat food containing gluten because gluten could damage
the villi in her small intestine. Damaged villi result in poor absorption of digested
food and this in turn causes diarrhoea.
a
Using your knowledge of enzymes, explain why proteases produced in the
body of Tracy can digest proteins in meat but not gluten in wheat. (3 marks)
b
How does poor absorption of digested food cause diarrhoea?
(4 marks)
5. Some digestive enzymes are secreted as non-functional enzymes (proenzymes) from
glandular cells; further processing in the gastrointestinal tract will turn the
proenzymes into functional enzymes.
a
Name the organelle in which enzymes are assembled. (1 mark)
b Suggest a type of digestive enzyme that is most likely secreted as a
proenzyme. What is the significance of producing this digestive enzyme as a
proenzyme within the glandular cells, instead of directly secreting the functional
enzyme? (2 marks)
c
During processing in the gastrointestinal tract, part of the proenzyme molecule
is cut away. Explain how the remaining part turns into a functional enzyme.
(2 marks)
6.
Read the following article and answer the questions.
Sinuses (竇) are a group of hollow air spaces within the skull surrounding the
nose. They help in insulating the skull, reducing the weight of the skull and
allowing the sound to resonate in the skull.
The sinuses are lined with mucus-secreting cells and ciliated epithelial
cells. Under normal conditions, the mucus produced by the cells is drained
into the nasal cavity through openings of the sinuses. When the respiratory
tract is infected, the lining of the nasal cavity swells up, blocking the openings
between the sinuses and the nasal cavity. The mucus is trapped inside the
sinuses. This may result in sinus infection called sinusitis (鼻竇炎).
Symptoms of sinusitis include facial pain and thick nasal secretions.
Sinusitis normally ends on its own. If the symptoms last for a long period of
time, people should go to see a doctor and receive medical treatments.
a
State the functions of mucus and cilia in the sinuses.
(2 marks)
b
How does the mucus trapped in the sinuses result in sinusitis?
(1 mark)
c
Suggest another symptom of sinusitis with a reason.
(2 marks)
7. The diagrams below show a capillary bed and the water potential changes when the
blood flows through it.
a
Why does the water potential keep constant along the arteriole and venule?
(2 marks)
b
Explain the change in the water potential of the blood in the capillary.
(5 marks)
c
Tissue fluid formed near the capillaries is drained into the lymph capillaries,
which join to form lymph vessels. Describe how the lymph flows in the lymph
vessels.
(2 marks)
d
State one function of the lymphatic system.
(1 mark)
8. The diagram below shows a model which demonstrates the breathing process of
humans.
a
b
Which structures of the human breathing system do the following parts of the
model represent? (2 marks)
i
the plunger
ii
the balloon
iii
the syringe barrel
iv
the hole in the cork
i
What happens to the balloon when hole X is closed and the plunger is
pulled out at the same time? (1 mark)
ii
Which part of the breathing process does the process described in i ⠀
represent? (1 mark)
iii
Explain the mechanism of the process in ii in terms of the pressure in ⠀
space Y. (3 marks)
⠀
c
State one feature of breathing that cannot be shown by the model. (1 mark)
d
Hole X represents an injury to the thoracic wall, for example, a gunshot ⠀
wound. Describe how the injury will affect the breathing process. (2 marks)
9. A student carried out an experiment to investigate the effects of bile salts and lipase
on the digestion of lipids. He prepared 25 test tubes containing the same amounts of
whole milk and phenol red. Phenol red changes from red to yellow when the pH of a
solution changes from above 8.2 to below 6.8. He varied the amounts of bile salt
solution and lipase solution in each tube and added distilled water to make up to the
same volume. Then he measured the time required for the solution in each tube to
change from red to yellow. The table below shows the time in minutes.
Amount of bile salt solution (cm3)
Amount of lipase
solution (cm3)
0
0.5
1
1.5
2
0
-
-
-
-
-
0.5
29
22
17
11
9
1
13
9
6
4
3
1.5
6
4
2
1
0.5
2
6
4
2
1
0.5
Remarks: ‘-’ indicates that the solution remained red after 30 minutes
a
What was the dependent variable in the above experiment and how was it ⠀
measured? (2 marks)
b
Explain why the solution in some tubes changed from red to yellow. (2 marks)
c
Draw three conclusions from the results. (3 marks)
d
Explain the effect of bile salts on the digestion of lipids. (2 marks)
10. The surface area to volume ratio of an organism varies with its size. The table below
shows two spheres X and Y which are used as models of organisms of different sizes.
The surface area and volume of each sphere are given.
Sphere X
Sphere Y
Diameter (cm)
2.5
7
Surface area (cm2)
78.5
615.8
Volume (cm3)
65.4
1436.8
a
b
i
The surface area to volume ratio of sphere X is 1.2. Calculate the ratio
of sphere Y. Show your working. (1 marks)
ii
Describe how the ratio changes as the size of the sphere increases.
(1 mark)
i
According to a, explain why large organisms like humans need
a breathing system but unicellular organisms like Amoeba does
not. (3 marks)
ii
Name the organ where gas exchange occurs in humans.
(1 mark)