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

133/2 BIOLOGY 2

For Both School and Private Candidates)

Time: 3 Hours Tuesday, 13th May 2014 p.m.

Instructions

1. This paper consists of eight (8) questions in sections A. B. C and D. 

2. Answer five questions by choosing at least one (I) question from each section. 

3. Each question carries twenty (20) marks.

4. Except for diagrams that must be drawn in pencil, all writing should be in blue or black ink. 

5. Cellular phones are not allowed in the examination room.

6. Write your Examination Number on every page of your answer booklet(s).

SECTION A

1. (a) Describe the structural adaptations of Entamoeba spp.

(b)Explain the advantages of algae to human being and other living things.

2.(a) Account for the general characteristics of the Phylum Apicomplexa.

(b) Describe the life cycle of Plasmodium falciparum and the effects it causes to its host.

SECTION B

3.(a) A father with blood group A and a mother of blood group B (both heterozygous) have four children. What is the probability that, the children will have blood group A?

(b) In the experiment conducted on pure-breeding varieties of oats, one with blackhulled grains and the other with white-hulled grains, the offspring (Fl) all had black-hulled grains. When Fl generations were crossed they gave F2 generation with the following phenotypes:

(i) 418 - black-hulled grains, 

(ii) 106 — grey-hulled grains and 

(iii) 36 - white-hulled grains.

Use the punnet square to show the gametes, genotype and phenotypes in each generation and suggest the genetic ratio.

4.(a) Elaborate Mendel's work in genetics by considering his success and failures. 

(b) Show the probability ofhaving haemophiliac children when a carrier haemophiliac woman marries a normal man.

SECTION C

5.(a) Explain how mitosis is significant in living organisms.

(b) With reference to housefly and grasshopper, describe in detail the process of metamorphosis in each.

6.Describe how mammals are adapted to warm environment. 

SECTION D

7.(a) Describe the two types of competition and briefly explain why intraspecific competition is density dependent.

(b) Explain six ways in which excess intraspecific competition is avoided among organisms in the ecosystem.

8.Elaborate how primary and secondary ecological successions take place.