Biology Scheme Pertgh Penggal 2

8/4/2019 Biology Scheme Pertgh Penggal 2

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1. Diagram 1 shows the different stages which take place during cell division.

(a) Name the cell division shown in Diagram 1.Mitosis

[1 mark]

(b) Arrange the stages in Diagram 1 according to the correct sequence of events during cell divisionL , N , K , M

[1 mark]

(c) Name the stages labelled K and N?K : Anaphase (early )

N : Metaphase

[2 marks]

(d) Explain the behaviour of chromosomes during stages K and N.K : Sister chromatids separate and move towards to the opposite poles of the cell

N : Chromosomes align/lined up at the metaphase plate // 2 sister chromatids are attached

to the spindle fibre by their centromeres

[2 marks]

Diagram 1


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Diagram 2 shows an experiment carried out on animal cloning by using two different species of frog

(e) Based on Diagram 2, state the meaning of cloning.Cloning is a process to produce a new frog which is identical to its parent by mitosis

[1 mark]

(f) Name the type of reproduction shown in Diagram 2. Give a reason for your answer.Asexual reproduction (1 m). The production of offspring is not involving the process of

fertilization (1 m)

[2 marks]

(g) Describe why a mature intestinal cell is used in this experiment. Give two reasons.- Mature intestinal cells are able to undergo mitosis /cell division by mitosis.- Have all the necessary factors required for a complete cell division

[2 marks]

(h) (i) Based on Diagram 2, name the species of frog that will be produced at the endof the experiment.

Species Y

[1 mark]

(ii) Explain your answer in (h) (i).

Nucleus of the frog is obtained from species Y

[1 mark]

Diagram 2

Species X

Ovum A

BOvum withoutnucleus

C

D

Intestine is removed from

the tadpole

UV light

Nucleus is sucked out

from the intestine

Nucleated egg cell fused

with the nucleus of

intestinal cell

Species Y

F

E


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2. Diagram 3 shows the levels of cell organisation in human.

(a) State what a cell is.Is a basic unit of life / living organism

[1 mark]

(b) Name Cell P and Tissue QCell P : Epithelial cell

Tissue Q : Smooth muscle tissue

[2 marks]

(c) Based on Diagram 3, explain the organisation and function of Tissue Q and stomach.Tissue Q : Made up of many smooth muscle cells .

Perform / carry out (specific function) muscle contraction /contraction of stomach wall

Stomach : Made of many Tissue Q / epithelial tissues and smooth muscle tissues

Perform / carry out (specific function) the digestion of food / protein

[4 mark]

(d) State the Level R of cell organisation.Organ

[1 mark]

Smooth muscle cell

Tissue Q

Gastric

gland

Level R

Tissue P

Cell P

Tissue

Cell

Stomach

Diagram 3


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(e) (i) Name the food molecules that are digested in the stomach and the enzyme forthis reaction.

Food molecules : protein //caseinogens (soluble milk protein)

Enzyme : pepsin // rennin

[2 marks]

(ii) Describe how the hydrochloric acid produced by the gastric glands help in the

digestion of food molecules in the stomach.

Provide acidic medium for the optimum reaction of enzymepepsin in stomach / stop the

activity of salivary amylase / helps to kill bacteria in food

[2 marks]

3. Diagram 4(a) shows the human digestive system.

(a) (i) State the difference between mechanical and chemical digestion.

Mechanical digestionbreakdown of large pieces of food into smaller pieces with aid of

teeth.

Chemical digestionbreakdown of complex food into simple soluble substances /

molecules. Process requires digestive enzymes.

[2 marks]

Diagram 4(a)


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(b) (ii) State the difference between absorption and assimilation.

Absorptionmovement of simple soluble molecules/ substances across intestinal wall of

the alimentary canal into the bloodstream

Assimilation

utilisation of absorbed food by body cells for energy , growth, reproduction

, repair

[2 marks]

(c) Name the structures P and Q.

P : Deodenum

Q : Pancreas

[2 marks]

(d) Describe how Q is involved in the digestion of fats and starch in P

Pancreatic juices containing lipase and pancreatic amylase transported from Q to P. Lipase

hydrolyse tiny droplets of fats to fatty acids and glycerol . Pancreatic amylase hydrolyses

starch to maltose

[2 marks]

(f) Diagram 4(b) shows two types of fats

(i) State the type of fats shown in Diagram 4(b)

R : Saturated fat S: Unsaturated fat

[2 marks]

(ii) A girl takes food from group R continuously for a long period of time. Explain the

consequences to the health of her heart.

Able to explain the consequences of taking food from group P for a long period time

Diagram 4(b)


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Sample answer:

- Food from group P contains high level of cholesterol (1m)- Cholesterol//fatty deposits tend to accumulate on the inner wall of arteries (1m)- Causes the narrowing of the blood vessels/ coronary arteries are blocked by the built-up of

fatty tissues (1m)

- Reduces the flow of blood (1m)- The heart muscles become starved of oxygen and dies (1m)- The girl might get heart attack (1m) MAX: 3 marks

[3 marks]

4. Diagram 5 represents the structures offour organic compounds which are found in living cells.

(a) (i) Name the compounds of X and ZX : polypeptides / protein

Z : lipid / fat

[2 marks]

(ii) State the monomer of X and Y

X : amino acid

Y : glucose / fructose / galactose

[2 marks]

(b) (i) Monomer X can be divided into 2 groups, which is essential and non-essential of monomerX. State the difference between these two groups.

W

Diagram 5


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Essential amino acids cannot be synthesised by the body while non essential amino acids

can be synthesised by the body

[1 mark]

(ii) State the reaction that leads to synthesis of compound Z.

1 molecule of glycerol + 3 molecules of fatty acids

[1 mark]

(c) What would happen if pancreatic cells are unable to synthesis compound X?Enzymes / any pancreatic enzymes / hormones cannot be synthesised

[1 mark]

(d) (i) In the space below draw and label the structure of the basic unit of organic compound W.

[2 mark]

(ii) Name two type of organic compound W.

RNA and DNA

[1 mark]

(iii) State 2 differences between the organic compounds you have named in (d)(ii)

RNA DNA

Found in cytoplasm , ribosomes , and

nucleus

Found in nucleus , chloroplast ,

mitochondria

Consists of one strand of

polynucleotide

Consists of double strands

polynucleotide

Strand of polynucleotide is linear Strands of polynucleotide are twisted

each other / double helix

[2 marks]


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5. Diagram 6 shows three organisms P , Q and R.

(a) (i) Describe the type of nutrition in P and Q. [4 marks](ii) Explain one similarity and four differences for the alimentary canals and types of nutrition

between Q and R. [10 marks]

(b) Based on the statement above, state the causes and suggest ways on how to overcome thehealth problems mentioned in the statement. [6 marks]

7 (a) (i) Organism P shows autotrophic nutrition. Able to synthesis their own food / complex organic

substances. Eg : green plant synthesise carbohydrates from inorganic substances such as carbon

dioxide and water (2m)

Organism Q shows heterotropic nutrition. Unable to synthesis its own food. Feed on food

substances from other organisms (2m)

7 (a) (ii) Similarity :

Both have alimentary canals which are unable to secrete enzyme cellulase to digest cellulose

Differences:

Organism Q Organism R

Ruminant Rodent

Made up of 4 chambers Has one stomach only with no division of

chamber

No caecum and appendix Has large caecum

Food digested twice by regurgirating and

rechewing before being swallowed again

Faeces are eaten twice for a secong round of

digestion

Poor eating habits result in health problems such as obesity, anaemia and constipation

Diagram 6


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Cellulose is digested in the stomach Cellulose is digested in the caecum and

appendix

Microorganisms are found in rumen and

reticulum

Microorganisms are found in caecum and

appendix

7 (b) Obesity

Obesity is often caused by consumption of excess carbohydrates and fats and lack of exercise.

People who are obese should reduce intake of fats and carbohydrates and carry out more exercise.

Anaemia

Anaemia may be due to insufficient red blood cells or the available red blood cells do not contain

sufficient haemoglobin to transport oxygen

Anaemia often results from a deficiency of nutritional factors (eg: iron , vitamin B12) required to

synthesis haemoglobin or RBC. It may also be caused by excessive loss of blood or destruction of

the cells

There should be an increase in the intake of iron and vitamin B12 if anaemia is caused by the

deficiency of these factors

Constipation

Constipation is the difficulty elimination of faeces from the body

Eating more food high in dietary fibre and drink more fluid/water to prevent constipation

Documents

Biology Scheme Pertgh Penggal 2