THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL OF TANZANIA CERTIFICATE OF SECONDARY EDUCATION EXAMINATION

BIOLOGY

(For Both School and Private Candidates)

Time: 3 Hours Year: 2005

SECTION A

1. For each of the items (i) - (x), choose the correct answer from among the given alternatives and write its letter beside the item number.

(i) Rickets is a common feature in young children lacking one of the following vitamins:

1. C
2. A
3. D
4. B
5. K

Study the diagram below (Figure 1) and answer question (ii) to (iv).

Fig. 1

(ii)The structure which is responsible for food storage is:

1. B
2. A
3. D
4. E
5. C

(iii)Vegetative propagation occurs due to the presence of structure:

1. B
2. A
3. D
4. E
5. C

(iv)Figure 1 above represents a:

1. rhizome 
2. stem tuber
3. root tuber
4. bulb 
5. stolon

(v)Which one of the following tissues is meristematic?

1. cornified layer of the skin 
2.  collenchyma
3. cambium 
4. sclerenchyma
5. xylem

(vi)The concept of good health implies . . . . . . . . health,

1. sexual, physical and mental
2. physical, mental and social
3. mental, sexual and physical
4. physical, mental and family
5. reproductive, social and family

(vii) Figure 2 shows a section of a villus. 

Which part is a lymphatic vessel?

Fig. 2

(viii) When red flowered pea plants crossed with white flowered pea plants, all the Fl generation had pink flowers. This is an example of:

1. Crossing over 
2. Mutation
3. Incomplete dominance
4. Recessiveness 
5. Inbreeding

(ix)The Figure below shows a section of a root tip.

Fig. 3

Which part of the root tip undergoes rapid cell division?

1. A
2. B
3. C
4. D
5. A and B

(x)Study the following sequence of organisms:

Grass → Rabbit  →  Wolves  →  Fleas

The sequence is an example of:

1. a food web 
2. a food chain
3. an ecosystem 
4. a pyramid 
5. a community

2. Match the phrases in List A with the responses in List B by writing the letter of the correct response beside the item number.

SECTION B

3. (a) Figure 4 shows the structure of a hip joint in the mammalian skeleton.

Fig. 4

(i)Name the parts labelled A, B, C, D, E, and F.

(ii)State the functions of parts B, C and D.

(iii)Name the type of joint represented by Figure 4 and state the characteristics of such a joint. Fig. 4

(b)(i) Name the process in Figure 5 below.

Fig. 5

(ii) If the sperm cell carried an X-chromosome, what sex would the developing foetus be?

(iii)Name a hormone that controls the development of female secondary sexual characteristics.

(iv)Write one (1) example of a human female secondary sexual characteristics.

4. Figure 6 shows a germinating bean seed.

Fig. 6

a) During germination, enzymes are released in the cotyledon to digest stored food.

(i)Name the enzymes which will digest stored protein and starch.

(ii)The enzymes which digest protein cannot digest starch. Why?

(iii)The beans did not germinate when planted in acidic compost. What effect did the acid have on the bean's enzymes?

(b)What is the function of starch stored in a bean to the human body?

5.(a) What is shock?

(b)What are the causes of shock?

(c) List down four (4) causes of fainting.

6.(a) What is variation?

(b) Differentiate continuous variation from discontinuous variation.

(c) In an experiment, a variety of garden peas having a smooth seed coat was crossed with a variety having a wrinkled seed coat. All the seeds, in the F1 generation were self crossed and the total number in F2 generation was 7324,

(i) Using appropriate letter symbols, work out the genotype of the F1 generation.

(ii)From the.information above, write the total number of wrinkled seeds in the F2 generation.

7. (a) Figure 7 shows the arrangement of tissues in a dicotyledonous plant.

Fig. 7

(i)Name the parts labelled A, B, C, D, E, and F.

(ii)State the functions of parts A, B, E and F.

(iii)From which part of the plant body was the section taken? Give reason.

(b)What are the functions of roots in plants?

8.Explain why:-

(a) It is possible for a person to swallow something while standing on his head.

(b) One does not urinate frequently on a hot day.

(c) Cell turgidity in plants is necessary.

9.(a)(i)What do you understand by the term mulching? 

(ii) What are the advantages of mulching?

(b)(i) List down the characteristics of viruses. 

(ii) How do viruses differ from bacteria?

10.(i) Distinguish between gaseous exchange and breathing.

(ii)What is the importance of gaseous exchange?

(iii)List down the factors governing gaseous exchange at the alveoli of the lungs.

(b) Name the organ/structure and the organism to which the following respiratory surface belongs: 

(i) Alveoli

(ii)Gill lamellae

(iii)Lining of buccal cavity

(c) Tracheae at is the economic importance of the process of fermentation?

SECTION C

11. (a) What do you understand by the term environment? 

(b) Discuss how farming affects the environment.

12. (a) Write an essay on "Drug abuse" using the following sub-headings:(a) Meaning of drug abuse

(b) Examples of common drugs

(c) Causes of drug addiction and how to control drug addiction 

(d) Effects of drug abuse

(e) The socio economic hazards caused by drug abuse

13. (a)Trace the path of a red blood cell as it passes from the small intestine to the lungs.

(b) Outline the functions of blood.

(c) Explain why the wall of the left ventricle is thicker than that of the right ventricle.