PAST YEAR BIOLOGY

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2004/2005
2 FIGURE 3 shows homeostasis that regulates glucose level in blood

(a) What is meant by homeostasis? [1 mark]
The process of maintaining a stable internal body environment //
regulation of chemical (and physical) composition of body fluids

(b) Give the names of hormone J and K as well as the cells that secrete these hormones.
[4 marks]

Hormone Name of hormone Cells that secrete hormone
Insulin β - cells of Islet of Langerhans

J α - cells of Islet of Langerhans

Glucagon
K

(c) At high glucose level, what will happen if hormone J is secreted [3 marks]

(i) Stimulates the conversion of glucose to glycogen

(ii) Stimulates uptake / transport of glucose into cells / body cells take up more

glucose

(iii) Stimulates storage or conversion of glucose to amino acid and fat

(iv) This reduces glucose level back to normal

(d) Name the mechanism A and B in FIGURE 3? [2 marks]

A: Negative feedback mechanism
B: Negative feedback mechanism

Session 2005/2006

51

PSPMCompilation of Biology Past Year’s Questions SB026

3 FIGURE 3 shows the structure of nephron.

(a) Give THREE factors that increase the efficiency of the process occurring in H. [3 marks]
- high hydrostatic pressure// high blood pressure// high resistance to blood
flow// afferent diameter is larger than efferent// blood flow is slow
- high surface area/ coiled blood capillaries
- high permeability
- more porous// high number of pores

(b) Name one process that occurs in J. [1 mark]
Active transport // osmosis// absorption// reabsorption// secretion

(c) What happens to the filtrate when it moves along K? [2 marks]
More NaCl is actively transported out by active transport

(d) Why does a desert rat have longer tubules K and L? [1 mark]
To avoid excessive water loss// more water can be reabsorbed

(e) What is the effect of ADH? [1 mark]

ADH caused the walls of the (distal convoluted) tubules and (collecting ducts) to

become more permeable to water// ADH increase reabsorption of water in the (distal

convoluted) tubules and the (collecting ducts)

(f) Give an example of a substance that is secreted into tubule M. [1 mark]
Potassium ion// Hydrogen ion// urea// drug [1 mark]

(g) State the process that occurs in N.
Reabsorption of NaCl/ water

52

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2007/2008
4 FIGURE 4 shows the structure of a nephron in a human kidney.

(a) What is meant by homeostasis? [1 mark]

The process of maintaining biologically stable conditions inside a living organism/

body (through physiological processes)

(b) (i) What is the process that occurs in X? [1 mark]
Ultrafiltration

(ii) State one reason why this process occurs in X. [1 mark]

Afferent arteriole larger than efferent arteriole//high hydrostatic blood pressure

in the glomerular capillaries

(c) (i) Which part of the nephron that a major decrease in volume of the glomerular filtrate

occurs? [1 mark]

Proximal convoluted tubule

(ii) Glucose is present in the glomerular filtrate but absent in the urine of a healthy

person. Explain what happens to the glucose. [2 marks]

- Fully reabsorbed into blood/capillary/ the vasa recta

- By active transport // because high renal threshold level

(d) Why do desert animal have longer structure Y? [2 marks]
- Longer Y will create more hypertonic medulla
- More H2O can be reabsorbed into vasa recta (less H2O loss)
- Produce more hypertonic urine

(e) Structure Z is important in the regulation of the blood and body fluid composition

equilibrium. Name TWO substances that are regulated by structure Z. [2 marks]

H2O, Na+, HCO3 - ,K+ , Mg2+

53

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2011/2012

6 TABLE 1 shows the concentration of various solutes in the blood plasma entering the
kidney, glomerular filtrate and urine of a healthy person.

Concentration of solute (g/1000 ml)

Solute Blood plasma entering Glomerular filtrate Urine
the kidney
Urea 0.25 0.25 0.10
Glucose 1.00 1.00 0.00
Protein 70.00 0.20 0.00
3.00 3.00 0.30
Na+ 3.50 3.50 0.35
Cl-

TABLE 1

(a) State the process by which dissolved nutrients in blood plasma enter the
Bowman’s capsule.

Ultrafiltration [1 mark]

(b) Give THREE characteristics of the blood vessels in the glomerulus.[3 marks]

- Diameter of afferent arteriole is larger than efferent arteriole
- Permeable to water and solute // not permeable to blood cells and

plasma protein
- Porous capillaries

(c) Why does the glomerular filtrate contain very little protein? [2 marks]

- Most protein molecules are large
- They cannot be filtered out of the glomerulus

(d) Why is glucose not found in the urine? [1 mark]
All the glucose is reabsorbed

(e) What are the effects on urine formation if a person accidently drank a lot of sea

water while swimming? [3 marks]

- More water is reabsorbed
- Urine volume decreases
- Urine is more concentrated

54

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2012/2013
3 FIGURE 2 shows the structure of a nephron.

FIGURE 2

(a) Name P, Q and R. [3 marks]
P: Proximal (convoluted) tubule
Q: (ascending) loop of Henle
R: Distal (convoluted) tubule

(b) Which parts reabsorb water into blood vessels? [1 mark]

Proximal (convoluted) tubule, distal (convoluted) tubule, collecting

tubule/duct and descending loop of Henle

(c) (i) Which part plays the most important role in regulating water level in

kidney? [1 mark]
Collecting tubule/ duct

(ii) Give a reason for your answer in 3(c)(i). [1 mark]

ADH increase permeability of collecting tubule towards water /
ADH acts on collecting tubule/ duct // has aquaporin channels

(d) (i) State TWO unique features of P. [2 marks]

Coiled and lined with numerous microvilli.
Contains many mitochondria.

(ii) Give the significant of the features mentioned in 3(d)(i) [2 marks]

(coiled and microvilli are) to increase the surface for the

reabsorption processes.

(Mitochondria are) to provide energy for active transport.

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2016/2017
3. FIGURE 3 shows the structure of a nephron in the human kidney

FIGURE 3

(a) Name the structures labelled Q and R. [2 marks]

Q : Proximal (convoluted) tubule
R : Collecting duct

(b) State the main process which occur in structures P and S. [2 marks]

P : Ultrafiltration
S : Reabsorption

(c) State the substance that is absent in structure P and give a reason.
[2 marks]

Protein // Red blood cell // White blood cell // Platelet // blood cells
They are too large to pass through the filter / glomerulus

(d) Explain the absence of glucose in the urine. [2 marks]

All glucose has been reabsorbed (into the blood capillaries)
In the proximal tubule (of the nephron)

(e) Explain briefly how the concentration of substances in the urine changes after a
heavy intake of meat.
[2 marks]
Meat protein are hydrolyzed into amino acids and are converted into urea
(in the liver)

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PSPMCompilation of Biology Past Year’s Questions SB026

Concentration of urea in the urine increases
______________________________________________________________
Session 2008/2009

(a) Discuss why urine becomes more concentrated and less when someone drinks
less water?
[8 marks]

Session 2013/2014

(a) Explain the concept of homeostasis and its control system. [12 marks]

(b) Breifly describe the general function of nephron and state its main component
[8 marks]

57

PSPMCompilation of Biology Past Year’s Questions SB026

21.0 COORDINATION
Session 2005/2006

1. FIGURE 1 shows the responses to daylength of two different plants for flowering.
Phytochrome is one of the factors involved in the control of flowering.

FIGURE 1

(a) (i) Which of the plants will flower earlier when exposed to day length of

more than 16 hours per day? [1 mark]

F

(ii) Why? [1 mark]
F is a long day plant

(b) What is the effect on flowering of plant E if the daylength is less than 12 hours

per day? [1 mark]

Flowers early / faster

(c) Classify the plants in FIGURE 1 based on the following types: [2 marks]

(i) Long day plant :F
(ii) Short day plant :E

(d) In Cameron Highland, commercial planting of plant F uses artificial light at

night. Why? [2 marks]

Lengthen the day length / light period // more Pr coverted to Pfr. Day

length of more than 12hrs/ day stimulate flowering

(e) How does phytochrome trigger flowering? [3 marks]

Inactive pigment absorbs red light. Pr transforms to active form / Pfr

stimulate biological response for flowering

58

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2009/2010
1 FIGURE 4 shows the action potential in a neuron.

FIGURE 4

(a) What is meant by an action potential? [2 marks]

The change in electrical potential that occurs across a cell membrane

during the passage of a nerve impulse // An electrical signal resulting

from depolarization of the plasma membrane in a neuron or muscle cell //

A rapid voltage

(b) Name the phases Q and R. [2 marks]

Phase Q : depolarization // rising phase of action potential

Phase R : repolarisation // falling phase of action potential

(c) Based on FIGURE 2, state at which phase does the following processes

happen. [3 marks]

(i) Na+ channels close and K+ channels open : R and S

(ii) Na+ and K+ channels close :P

(iii) Positive feed-back :Q

(d) Impulse move from one nerve cell to another nerve cell through synaptic cleft.

(i) State the function of hydrolytic enzyme that can be found in synaptic

cleft. [1 mark]

To breakdown / hydrolyse neurotransmitter / Acetylcholine

(ii) What is the role played by calcium ions (Ca2+) in synaptic transmission?
[1 mark]

Cause the synaptic vesicle to fuse with the presynaptic membrane

(iii) State the function of mitochondria in impulse transmission.
[1 mark]

To produce ATP for the synthesis of neurotransmitter / reuptake of
neurotransmitter

59

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2014/2015
4 FIGURE 4 shows the nervous system of a vertebrate.

FIGURE 4

(a) Label X and Y. [2 marks]
X : Central nervous system / CNS
Y : Peripheral nervous system / PNS\

(b) State the function of Y. [2 marks]

Y transmits signals / impulse from the sensory organs / receptors to the

central nervous system.

Y transmits the signals / impulse from the central nervous system to

organs / muscles / effectors

(c) Name the functional unit of the nervous system. [1 mark]
Neuron / nerve cell

(d) What happens when cocaine binds to the transporter proteins of the nervous

system? [3 marks]

Reabsorption of dopamine is blocked // Dopamine cannot enter synaptic

knob / presynaptic membrane

Dopamine accumulates / stays in the synaptic cleft

Dopamine stimulates the receptors repetitively continuously

(e) Briefly explain the events that occur when acetylcholine binds to the receptors

on the plasma membrane of a muscle fibre. [2 marks]

The sarcolemma / plasma membrane of muscle fibres becomes

permeable to sodium ions // influx of sodium ions into muscle fibres

This depolarises the postsynaptic membrane // triggers an action

potential (muscle contracts)

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2016/2017
4. (a)

(b) FIGURE 4 shows a condition of skeletal muscle based on the sliding filament
mechanism.

FIGURE 4

(i) State the condition of the above muscle. [1 mark]
Fully contracted

(ii) Identify structures labelled M, N and O. [3 marks]
M: Myosin / thick filament
N: Actin / thin filament
O: Sarcomere

(iii) What happens to I band and H zone during the muscle condition shown

in FIGURE 4? [1 mark]

I band shortens and H zone disappears

61

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2003/2004

(a) With reference to a labeled diagram, describe the structure of a sarcomere. State
what happens to the myofibrils during contraction and relaxation of muscle.
[10 marks]

Session 2004/2005

(a) Describe transmission of impulse across the synaptic knob. [10 marks]

(b) Draw a labeled diagram of a synaptic knob. Describe how cocaine influenced the

transmission of impulse at the synaptic knob. [10 marks]

Session 2006/2007

(a) Explain the mechanism of non-steroid hormone action. [12 marks]
(b) List the effect of auxin in controlling plant physiology. [8 marks]

Session 2007/2008

(a) Describe how the axon membrane resting potential is established. [10 marks]

(b) Explain the roles of absisic acid hormones in seed dormancy, abscission and plant

growth. [10 marks]

Session 2008/2009

(a) How phytochrome regulates flowering in plants? [6 marks]

(b)Describe the events at the neuro-muscular junction and post-synaptic cell which

cause skeletal muscle to contract. [12 marks]

Session 2011/2012 [12 marks]
(a) Explain the propagation of action potential along the axon of neuron. [8 marks]
(b) Explain the role of phytochrome in controlling flowering.

Session 2013/2014

(a) Describe the transmission of impulse between two neurons. [10 marks]

(b) Describe myelinated axon and explain how action potential jumps from node to

node as it travels along the axon. [10 marks]

Session 2013/2014
(a) Compare the transmission of impulses at a synapse and along an axon.

[12 marks]

b) Describe the role of myelin sheath and suggest how the damage to the myelin sheath
interferes with the transmission of nerve impulses.

[8 marks]

62

PSPMCompilation of Biology Past Year’s Questions SB026

22.0 IMMUNITY
Session 2003/2004
1 FIGURE 4 shows the summary of the formation of lymphocyte cell and their roles.

(a) In which part of the human body the cells achieve maturity? [2 marks]
[2 marks]
B lymphocytes : bone marrow [2 marks]

T lymphocytes : thymus

(b) Name the types of immunity response shown in FIGURE 4.

Immune action X : humoral immune response
Immune action Y : cell mediated immune response

(c) Give TWO examples of helper cells.
TH 1/initiator cells/Helper T
TH 2/ stimulant cells/ Helper T memory

(d) Antigen-antibody interaction results in neutralization or destruction of microorganisms

that enter the body. State 4 methods of antigen-antibody interaction. [4 marks]

- Agglutination/ aggregation

- Lysis/ breaking up of cells/compliment fixation/activation of complement

- Neutralization/ neutralization of toxin

- Precipitation/ aggregation before drying up/ opsonisation

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2004/2005
2 FIGURE 4 shows humoral response during immunity formation.

FIGURE 4 [1 mark]
[4 marks]
(a) What is meant by antigen?
Foreign substances capable of stimulating an immune response [2 marks]
[1 mark]
(b) What are P, Q, R and S in FIGURE 4? [1 mark]
P : Lymphocyte B
Q : Plasma cells
R : Memory B cell
S : Antibodies

(c) What is the effect of an antigen action on P?
- To stimulate proliferation of B cells and
- Formation of antibody

(d) (i) How does helper T cell stimulate P?
By releasing IL-2

(ii) What is the function of helper T cell besides stimulating P?
Stimulate cytotoxic T cell become active killer cells

(e) State the effect of S on immunity system. [1 mark]
Can respond rapidly when subsequently exposed to the same antigen

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2005/2006
3 FIGURE 4 shows an immune response.

FIGURE 4 [1 mark]
(a) State the type of immune response.

Humoral immune response//Antibody- mediated response

(b) What is S? [1 mark]

Antigens (which originated from pathogen)//peptides fractions from

pathogen//peptides from bacteria

(c) After receiving information from the macrophage, T cell will secrete U. What is U and

state its function. [3 marks]

U : cytokines//lymphokine//interleukin

Function : - activates B cell

- to divide /proliferate

(d) What are cells P and Q? [2 marks]
Cell P : Memory (B) cells
Cell Q : Plasma (B) cells

(e) State 2 mechanisms of action of R. [2 marks]

Neutralization/Agglutination/Precipitation/Activation of complement system(to

increase phagocytosis)//To increase inflammation//lysis

(e) HIV is a virus that attacks immune system. State the cell infected by HIV. [1 mark]
T/T cell

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2006/2007
4 FIGURE 4 shows the antibody concentration in human after exposure to antigen A and

antigen B.

FIGURE 4

(a) What is meant by antibody and antigen? [2 marks]

Antibody : A type of protein produced by lymphocyte as a reaction/response

to the presence of antigens // Antigen binding protein

Antigen : Foreign) substances that trigger the production of antibody //

(Foreign) substances that trigger the immune response.

(b) State the level of development of immune response at P and Q. [2 marks]

P : Secondary immune response (to antigen A)
Q : Primary immune response (to antigen B)

(c) State TWO advantages of the antibodies characteristics produced at P compared to Q.
[2 marks]

- Greater affinity towards antigen / Faster response / Long lasting /

- Concentration is higher

(d) State the type of cell involved in the above immune response and the specific location

where it is produced. [4 marks]

Name of cell Location of production
Helper T cell Bone marrow
B cell // Memory B cell / plasma cell Bone marrow // Lymph node

66

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2008/2009
5 FIGURE 4 shows part of the mechanism of an immune response.

FIGURE 4 [4 marks]

(a) Name the cells labeled C, D, E and F.
C : Helper T (cell) // Th cell / TH cell// CD4 T Cell // T4 cell
D : Cytotoxic T (cell) // Tc cell // CD8 T cell // T8 cell // killer T cell
E : B (cell) / B lymphocyte
F : memory (cell) // memory B (cells)

(b) What is protein X? State its function. [2 marks]
Protein X : Interleukin -1 / IL-1 [1 mark]
Function : Activates the helper T cell

(c) State the location where cell C matures.
Thymus (gland)

(d) State the mechanism of action of cell D. [2 marks]
Cell D/Cytotoxic T cell binds/touch to the infected cell and destroy /kills it
By releasing protein/ perforin that destroy/ lyses target cell

(e) Which cell does HIV attack? [1 mark]

Helper T (cell) // Th cell / TH cell// CD4 T Cell // T4 cell/ lymphocyte/ macrophages/

dendritic/CD4+

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2013/2014
4 FIGURE 4 shows the immune responses after vaccination.

FIGURE 4

a) Define an immunity. [1 mark]

Resistance/ protection to specific body invaders/ bacteria/ pathogen

b) What type of immunity is shown in the graph above? [1 mark]
Artificial active immunity

c) i) What is A and B? [2 marks]
A : Primary immune response
B : Secondary immune response

ii) Give TWO differences between A and B. [2 marks]

- The rate of response of the primary immune response are slower compared to

secondary immune response// The rate of response of the secondary immune

response are faster/ rapid compared to primary immune response

- The magnitude of response/ concentration of antibody of the primary immune

response are smaller/ lower compared to secondary immune response// The

magnitude of response/ concentration of antibody of the secondary immune

response are greater/ higher compared to primary immune response

- The effect of primary immune response is short-lived while the effect of

secondary immune response is long-lasting

d) Name the class of antibody represented by X and Y. [2 marks]
X : Immunoglobulin G/ IgG
Y : Immunoglobulin M/ IgM

e) What is the difference between antigen and antibody? [2 marks]

Antigen is the trigger for immune response while antibody is the product of the

response

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PSPMCompilation of Biology Past Year’s Questions SB026

Session 2015/2016
4 FIGURE 1 represents the lymphoid system in human.

FIGURE 1

(a) Name the organs labelled X, Y and Z. [3 marks]
X : Tonsils/Adenoid/Lymph nodes
Y : Thymus (gland)
Z : Spleen

(b) Identify the type of lymphocytes mature in Y. [1 mark]
T lymphocytes/ T cell

(c) Describe briefly THREE functions of lymphatic system. [3 marks]

- Transport interstitial fluid/lymph fluid back into the bloodstream

- Assist fat absorption// transport fat/lipid from lacteal in small

intestine

- Protect body from invading organism/pathogen

(d) Differentiate between primary and secondary immune responses in the table

below. [3 marks]

Properties Primary Immune Secondary Immune

Response Response

Main antibody produce IgM IgG

Memory Produce memory cell Memory cell are active

are inactive/passive

Response rate Slow Fast/immediate

69

PSPMCompilation of Biology Past Year’s Questions SB026

Session 2010/2011

(a) Describe how self and non-self concept is applied in organ transplant. [10 marks]
Session 2011/2012

(a) Explain why kidney from a healthy donor is rejected by the recipients body after

organ transplant. [10 marks]

Session 2012/2013

(a) Explain the functions of the different classes of antibodies. [10 marks]

(b) Discuss the functions of different types of cells that occurred in humoral response.

[10 marks]

Session 2014/2015

(a) Describe the sequence of event in cell mediated immunity.
[12 marks]

(b) Discuss the immune responses involved when you are given a vaccination of BCG
at the age of one year old and a booster shot six months later.
[8 marks]

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