questions section b 1993-2003

8/12/2019 Questions Section B 1993-2003

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Questions (Section B) 1993-2003IGCSE BIOLOGY


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8

0610/3/O/N/02

Section B

Answer any two questions.

Write your answers on the separate answer paper provided.

4 (a) Explain how auxins in a shoot that is placed horizontally change the direction of its growth. [5]

(b) State the sites of production and describe the roles of oestrogen and progesterone

(i) in the menstrual cycle; [6]

(ii) during pregnancy. [4]

5 (a) Fig. 5.1 shows some of the features of a typical wind-pollinated flower.

Fig. 5.1

(i) Describe the features that make a typical wind-pollinated flower different from a typicalinsect-pollinated flower. [9]

(ii) Suggest how pollen of a wind-pollinated flower would be different from that of an insect-pollinated flower. [3]

(b) Outline the implications to a species of self-pollination. [3]

6 (a) Define the term respiration. [3]

(b) By means of a table, distinguish between aerobic respiration and anaerobic respiration. [5]

(c) Explain how a mammal regulates its body temperature after a period of strenuous exercise.[7]

7 (a) Distinguish between each of the following pairs of terms:

(i) phenotype and genotype;

(ii) dominant and recessive;

(iii) homozygous and heterozygous. [7]

(b) Using a suitable named example, explain how the following phenotypic ratios can be

obtained from a genetic cross.

(i) 1 : 1

(ii) 3 : 1 [8]


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8

0610/3/M/J/03

For

Examiners

Use

Section B



4 (a) (i) Describe the main similarities between insects and arachnids. [3]

(ii) By means of a table, show the differences between insects and arachnids. [5]

(b) Suggest and explain how a named insect could evolve over a period of time. [7]

[Total : 15]

5 (a) Explain why, in some parts of the world, not enough food is available to feed the people

living there. [10]

(b) Describe the uses of hormones in food production. [5]

[Total : 15]

6 (a) Explain the term codominance. [3]

(b) Using a suitably labelled genetic diagram, explain how a baby can have blood group O(IoIo) when its mother is group A and its father is group B. [6]

(c) (i) Describe and explain what could happen when blood of different groups is mixed.[3]

(ii) Describe and explain the role of the placenta in relation to this problem. [3]

[Total : 15]

7 (a) State the functions of five named parts of the male reproductive system. [5]

(b) (i) Explain how sperm, deposited in the vagina during sexual intercourse, reach an

egg. [4](ii) Describe the process of fertilisation. [3]

(c) Outline the ways in which HIV can be prevented from spreading. [3]

[Total : 15]


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0610/3/O/N/03

For

Examiners

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Section B



4 (a) Describe and explain, with reference to the ribs, intercostal muscles and diaphragm, theprocess of exhalation (breathing out). [7]

(b) By means of a table with suitable headings, compare the composition of inhaled andexhaled air, stating the reasons for similarities and differences. [8]

[Total : 15]

5 (a) (i) Construct a food chain with four named organisms. [3]

(ii) Using appropriate biological terms, describe and explain the flow of energy throughyour chosen food chain. [8]

(b) With reference to a suitable example for each, outline the need for conservation of

(i) anamed species

and

(ii) anamed habitat. [4]

[Total : 15]

6 (a) Describe the function of the immune system, including antibody production andphagocytosis. [9]

(b) Outline the problems of organ transplantation and how they can be overcome. [6]

[Total : 15]


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7 (a) With reference to a suitable example, define the term tissue. [3]

(b) Identify parts A,B,C andD shown on Fig. 7.1 and describe their main features andfunctions.

Fig. 7.1[12]

[Total : 15]

D

A

B

C

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questions section b 1993-2003

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