4551/2
4551/2
BIOLOGY/ AT
Kertas 2
Okt./Nov 2011
2 ½ jam
BIOLOGY
Tingkatan 4
Kertas 2
Dua jam tiga puluh minit
PERATURAN PEMARKAHAN
Peraturan Pemarkahan ini mengandungi 15 halaman bercetak
@ 2011 Hak Cipta MPSM Pahang
2
MARKING SCHEME
PEPERIKSAAN AKHIR TAHUN 2011 (TINGKATAN 4)
BIOLOGY 4551/2
No.
1(a)(i)
(ii)
(b)
Marking criteria
Marks
Able to label P and S.
Sample answers
P :
Plasma membrane
1
S :
Rough endoplasmic reticulum
1
Able to explain the function of the chromosomes.
Sample answers
1. Chromosomes carry / contain genetic information
1
2. which determines the characteristics / function of a cell
1
(d)
2
Able to explain what will happen to the production of extra cellular
enzymes if the Golgi apparatus and S are absent.
Sample answers
1. The production of extra cellular enzyme is incomplete
2. (Without S) the protein cannot be transported to Golgi apparatus
3. (Without Golgi apparatus) the protein cannot be modified (to form extra
cellular enzyme)
4. The protein cannot be sorted
5. The protein / enzyme cannot be packaged
6. No protein / enzyme will be transported / released out of the cell
(Any four)
(c)
2
1
1
1
1
1
1
4
Able to explain why the sperm cells contain more mitochondria.
Sample answers
F : Mitochondria generate energy // site for cellular respiration
1
E : Sperms need energy to swim (towards fallopian tube)
1
2
Able to explain how lysosomes help in eliminating damaged
organelles in the cells.
Sample answers
1. (Lysosomes) secretes hydrolytic enzymes / lysozymes
1
2. (Lysozymes) digest / hydrolyse the damaged organelles
1
TOTAL
2
12
3
2(a)
Able to name the structure labelled X.
Sample answers
Chromatid // Chromosome
(b)(i)
1
1
1
1
1
1
1
1
1
1
1
1
Able to complete the diagram in stage S to show the chromosome
behaviour.
Sample answers
Stage S
(ii)
sister chromatid/ chromosome separate
each of them moves to the opposite poles
Able to state one of the changes which occurs in stage S.
Sample answers
P1 - Chromosome separate
P2 - The chromosomes becomes chromatid
P3 - The chromatids move to opposite poles of the cell
(Any 1 P)
(c)(i)
Able to draw a diagram showing the appearance of the chromosome
at the end of process Y.
Sample answer
(ii)
The homologous chromosomes separate
There is exchange of genetic material in both chromosomes.
Able to name process Y.
Sample answer
Crossing over
4
(iii)
Able to state the importance of process Y to an organism.
Sample answer
1
1
To produce variation / source of variation in the organism
(d)(i)
Able to name two examples of factor W.
Sample answer
1
P1 : Rays – eg: X-rays/ radioactive / gamma rays
P2 : Chemical – eg: food flavoring / colouring / addictive / preservative /
carcinogenic substances/ drugs/ melamine
(ii)
(iii)
Able to explain the formation of cell X.
Sample answer
P1 – Factor W cause mutation / changes in genetics material / gene / RNA
/ DNA / chromosomes
P2 – Result in uncontrolled/ irregular cell division/ abnormal mitosis
1
2
1
1
2
Able to state two ways to prevent the development of cell X.
Sample answer
P1 – Prevent from exposure to radioactive rays/ any other rays examples
P2 – Prevent from taking in food containing addictive/ any other chemicals
P3 – Treatment of the disease
(Any 2 P)
TOTAL
1
1
1
Max
2
12
5
3(a)
Able to choose the letter that labels the part where each of the
following hydrolysis reaction takes place.
Sample answers
(i)
R
1
(ii)
P
1
2
(b)
Able to draw and label a longitudinal section of these projection
in the space below.
Sample answers
1
1
2
1
1
1
1
Epithelium
Epitelium
Lacteal
Lakteal
Blood capillary
Kapilari darah
(c)(i)
Diagram : one thick cell of epithelium layer
Labels : lacteal and blood capillary
Able to state the process that occurs in the projection drawn in (b).
Sample answers
Absorption of digested food.
(ii)
Able to state one characteristic of the structure T that will help
the process in (c)(i) to function efficiently.
Sample answer
1. Long and folded structure to provide a large surface area of absorption
2. Villus wall is semipermeable to allow certain substances to diffuse into
the blood capillaries or the lacteal
3. Movement of villi back and forth to make absorption faster
(Any one)
6
(d)(i)
Able to explain the effects of the removal of organ S on enzymes
and hormones, and how these affect the digestion and the level
of glucose in the blood.
Sample answer
1
1. Organ S is a pancreas. It removal causes the enzymes (pancreatic)
amylase to be no longer produced,
1
2. this disrupt the digestion of starch.
3. Removal of organ S resulted in no secretion of hormones insulin and
glucagon,
1
1
4
4. the level of glucose in the blood cannot be regulated.
(d)(ii)
Able to advice him to handle the health problems that may arise
from the removal of organ S.
Sample answer
1
1. Patient has to reduce the intake of foods containing starch
2. because of the absence of pancreatic amylase which makes starch
cannot be digested in the small intestine.
1
TOTAL
4(a)
2
12
Able to name the respiratory system for organism X and Y.
Sample answer:
X : Tracheal system
Y : Gill System
(b)
1
1
2
Able to explain the functions of structures labelled S and T.
Sample answer:
S : An opening to let the air flow in and out of the trachea
T : To prevent the trachea from collapsing
(c)(i)
1
1
2
1
1
Able to explain how the fluid help in gaseous exchange.
Sample answer:
Oxygen dissolves in fluid and there is able to be absorbed into the muscle
cell
7
(c)(ii)
Able to explain how air moves along the structure T in organism X.
Sample answer:
1. Rhythmic contraction and expansion of abdomen muscles
1
2. helps the intake and outtake of air absorption through the spiracle and
1
2
1
1
trachea
(d)(i)
Able to state where does gaseous exchange occur in organism Y
Sample answer:
Gill filament
(d)(ii)
Able to explain the answer in (d)(i)
Sample answer:
1. Dissolved oxygen in the water will be absorbed into blood capillaries on
1
the gill filament
2. Carbon dioxide will be excreted out through the gill capillaries into the
1
2
Water
(e)
Able to explain the difference between gaseous exchange in X and Y.
Sample answer:
1. On organism X, direct gas exchange occurs between the tracheal and
1
body cells, without involving blood as a transport medium.
2. On organism Y, gas exchange occurs through the gill filament and blood
1
2
acts as an oxygen carrier.
12
TOTAL
5(a)(i)
Able to name the type of interaction represented by P and Q.
Sample answer:
P: Mutualism / symbiosis
1
Q: Commensalism
1
2
8
(ii)
(b)(i)
Able to describe the interaction represented by P.
Sample answer:
1. Nitrogen-fixing bacteria/Rhizobium in nodules of root
1
2. fix the nitrogen to form ammonia compounds which is used by the plant
1
3. while Rhizobium get shelter/energy from the plant
1
Able to state the terms are used to describe organisms X and Y.
Sample answer:
Organism X : Epiphyte
1
Organism Y : Saprophyte
(ii)
1
1
1
Able to explain what will happen to organism X.
Sample answer
1
1. X continues to grow
1
2 .because able to photosynthesize/ synthesizes own food..
(d)
2
Able to state one characteristic of organism X.
Sample answer
-The presence of aerial roots (which absorb moisture from the air)
- has false bulb
(c)
max
2
2
Able to explain how mushrooms can grow on saw dust.
Sample answer
1. Mushrooms grow on dead organic matter.
1
2. Mushrooms secrete enzymes
1
3. which digest the complex organic matter
to simple substances.
1
4. mushrooms absorb organic material for growth
1
max
3
TOTAL
12
9
Mark Scheme
No
6(a)
Marks
Able to explain the regulatory mechanism of oxygen and carbon
dioxide contents :
Sample answers
(i)
During vigorous activity :
E1 : The partial pressure of carbon dioxide increase as a result of
active cellular respiration
E2 : Because carbon dioxide reacts with water to form carbonic acid
// equation
E3: Higher carbon dioxide concentration level in blood results in a
drop in pH value of blood and cerebrospinal fluid
E4 : The drop in pH is detected by central chemoreceptor
( in medulla oblongata )
E5 : Send impulse to respiratory centre
E6 : The respiratory muscles contract and relax more / faster
E7 : Breathing and ventilation rate increase
E8 : As excess carbon dioxide is eliminated , concentration and pH
value of blood return to normal level
( any 6)
(ii)
At high altitude :
Max
6
6
E1 : Decrease concentration of oxygen
E2 : Peripheral chemoreceptor / aortic bodies and carotid bodies
stimulated
E3 : Send impulse to respiratory centre
E4 : Heartbeat rate increase
E5 : Breathing rate and ventilation increase
E6 : More oxygen is inhaled and the oxygen concentration return to
normal level
Max
4
( Any four)
4
10
(b)
Able to name the two process shown in figures :
Sample answer
F1 : Respiration
F2 : Photosynthesis
Able to state the comparison between respiration and photosynthesis
Sample answer
Respiration(R)
Item
Photosynthesis(P)
All living organisms
Organisms
involve
Occurs during day and
night
When it occurs
Only in green plants //
photosynthetic bacteria
Occurs only on day time
//
at
certain
light
intensity
As
an
anabolism
process // synthesis of
complex molecules from
simpler molecules.
As a catabolism
process // metabolism
process that break
down of molecules to
smaller ones.
Glucose and oxygen
are used while the
carbon dioxide and
water are released
Chemical energy is
converted to chemical
energy / ATP and heat
energy
Energy, water and
carbon dioxide
Process
Reaction
Exchange of
energy
Products
Carbon dioxide and
water are used while
oxygen and glucose are
released
Light
energy
is
converted to chemical
energy
Glucose and oxygen
Mitochondrion
Organelle
Involved
Chloroplast
C6H12O6 + 6O2 -
6CO2 + 6H2O + energy
Chemical
equation
6CO2 + 6H2O
C6H1206 + 6O2
Notes
R – Respiration
P – Photosynthesis
[ R and P are dependent ]
-
( Any five pairs)
TOTAL
Max
10
10
20
11
7
(a)(i)
Able to state the meaning of balanced diet.
Sample answer
P1 - Comprises all seven classes of food, namely carbohydrates, proteins,
fats, minerals, vitamin, water and roughage
P2 – according to the body’s needs
P1  , P2  = 2 m
P1  , P2 X = 1 m
P1 X , P2  = 0 m
(a)(ii)
2
2
Able to discuss the importance of each class of food;
Sample answer
Protein :
-
As a component of protoplasm
1
-
Produce new cells for growth
1
-
Repairs tissues
1
-
Produce enzymes, antibodies, haemoglobin, certain hormones
1
-
As a source of energy during starvation
1
(Any four)
Max
4
Water :
-
Makes up approximately 70% of body weight and 90% of
protoplasm
1
-
Serves as a solvent
1
-
Medium of reactions
1
-
Plays a role in transporting food, carbon dioxide and removing
nitrogenous waste
1
-
Helps regulate body temperature by releasing heat through sweat
1
-
As a lubricant in sinovial fluid found in the joints.
1
-
Helps eliminate metabolic waste such as urea, lactic acid and
1
excessive minerals through urine and sweat
1
Regulates the osmotic pressure of the blood and tissue fluid
1
-
(Any six)
Max
6
12
(b)
Able to explain the two conditions;
Sample answer
Obesity :
-
Excessive food intake
1
-
More than what is required by the body
1
-
More than 20% of the stipulated body weight according to the BMI
1
-
Excess food taken in stored as fat in the adipose tissue
1
-
Health problem associated are diabetes mellitus, high blood
1
pressure, stroke and cardiovascular diseases.
(Max : 4)
Anorexia nervosa :
8(a)
4
1
-
A type of psychological disease
1
-
Especially teenage girl
1
-
Worry about getting fat
1
-
Do not want to eat
1
-
Eat very little food
1
-
Excessive exercise
.
(Max : 4)
4
TOTAL
20
Able to explain why the mangrove system has to be preserved and
conserved.
Sample answer
E1 : Act as (shore protection// barrier against strong coastal winds/ wave//
waver breaker.
E2 : To prevent soil erosion/ landslide/ flash flood/ damage from tsunami
E3 : (Cable/ prop) root traps sediment/ soil/ rubbish/ garbage.
E4 : To maintain water quality.
E5 : Maintaining/ increasing biodiversity/ fauna species.
E6 : As a site for breeding / feeding of fauna/ relevant examples.
E7 : As a habitat for fauna/ animals.
E8 : Preventing extinction of fauna species.
13
E9 : Allow longer lifespan.
E10 : maintain balance ecosystem/ biodiversity.
E11 : Economical value/ source of raw materials for construction industry/
piling/ food / other suitable example/ research/ medicine.
E12 : As an ecotourism.
E13 : Maintaining the temperature/ minimize the climate change/ drought.
E14 : Reduce carbon dioxide/ provide oxygen.
E15: Prevent/ reduce green house effect/ global warming.
(b)
(Any ten)
Max
10
10
( Any ten)
Max
10
10
Able to explain the effect of an increase in carbon dioxide
concentration in the atmosphere on the ecosystem.
Sample answer
E1 :Green house effect.
E2 : Carbon dioxide trap / absorbed heat in the atmosphere.
E3 : (The layer of green house gases) act as an insulator/ barrier.
E4 : Cause a rise in temperature/ leads to global warming.
E5 : Melting of glacier/ ice berg.
E6 : Cause sea level to rise/ flood/ sinking of the island.
E7 : Cause changes in wind direction/ sea current.
E8 : Cause climate changes.
E9 : High temperature reduce the rate of photosynthesis.
E10 : Productivity of crop / livestock decrease.
E11 : Disruption of food chains / food webs.
E12 : Cause extinction of species/ biodiversity decrease.
TOTAL
20
14
9(a)
Able to explain how steamed fish is digested in part R, S and T in the
system.
Sample answer
F : steamed fish rich in protein(P)/ and fat(L)
P1 : Label R/ Stomach secrete pepsin.
P2 : Which hydrolysed protein to peptone/ polypeptide.
P3 : Equation P2
P4 : In acidic medium.
L1 : Fat is not hydrolised.
P5 : Label S / Duodenum received trypsin from pancrease
P6 : Peptones/ polypeptides is hydrolysed (by trypsin) to peptides.
P7 : Equation P7
P8 : In alkaline medium
L2 : Fat is emulsified/ change to tiny droplets// small particles.
L3 : Fat is hydrolysed by lipase to fatty acid ang glycerol.
L4 : Equation L3
P9 : Label T/ Ileum secrete erepsin/ peptidase
P10 : Peptidase is hydrolysed by erepsin/ peptidase to acid amino.
P11 : Equation P10
L3 : Fat is hydrolysed by lipase
L4 : Fat is hydrolysed to fatty acid and glycerol by lipase.
(Any ten)
Max
10
10
15
(b)
Able to explain the long term effect of consuming excess bread,
butter ang fried chicken on a person’s health.
Sample answer
Bread (C)
C1 : Bread is (rich) in carbohydrate.
C2 : High glucose content in blood.
B3 / C3 : Cause high blood pressure.
C4 : Diabetes(mellitus)/ glucosuria.
C5 : Excess glucose / glycogen is converted to fats.
C6 : Stored in adipose tissue/ under the skin.
B7 / C7 : Obesity.
Butter (B)
B1 : Butter is (rich) in fats / lipid
B2 : Result in high cholesterol level in blood.
C3 / B3 : Causes high blood pressure
B4 : Lipid / cholesterol deposited on/in (inner) wall of arteries.
B4A : Lumen arteries become smaller/ blood flow become slower/
blockage/ clog.
B5 : Arteriosclerosis/ angina/ stroke/ heart attack/ embolism.
B6 : Excess fat is stored in adipose tissue/ under the skin.
C7/ B7 : Obesity.
Max
10
10
Protein (P)
P1 : Fried chicken is (rich) in protein.
P2 : Excess amino acid is converted to urea/ ammonium compound.
P3 : Liver failure/ malfunction.
P4 : More urea to be removed( by kidney).
P5 : Kidney failure/ malfunction.
P6 : Excess uric acid will cause gout/ explain gout.
(Any ten)
TOTAL
MARK SCHEME END
PERATURAN PEMARKAHAN TAMAT
20