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: 2008

SECTION A

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

(i) When examining a cell from an unidentified organ of a mouse under an electron microscope, a student found an organelle with infolding in the inner membrane. Which organelle is it? 

1. Golgi body
2. Endoplasmic reticulum
3. Ribosome
4. Mitochondrion
5. Nucleus

(ii)Which of the following statements is true about eukaryotic cells?

1. They lack important organelles like smooth endoplasmic reticulum.
2. They are found in plants only.
3. Nuclear materials are enclosed within a membrane.
4. They are found only in animals.
5. They contain only little water.

(iii)Spitting, coughing and sneezing into a tissue paper are considered as: 

1. Waste disposal methods
2. Risk behaviors of spreading diseases
3. Good manners
4. Environmental pollution
5. A way of killing pathogens in the tissue.

(iv) Mr. and Mrs. Msakanjia, happened to have four children in their marriage. One of them is an albino. What is the possible genotype of Mr. and Mrs. Msakanjia?

1. AA x AA
2. Aa x aa
3. Aa x Aa
4. aa x aa
5. AA x Aa

(v) A mountaineer develops headache, breathlessness, nausea and vomiting on reaching an altitude of above 4000 metres. This is because: 

1. his body system is not given time to adjust to the low oxygen pressure.
2. the atmospheric pressure as well as the supply of oxygen decreases at higher altitude.
3. the increase in the amount of oxygen results into breåthlessness.
4. the atmospheric pressure increases at higher altitude and so does the supply of oxygen.
5. his body system is not given time to relax due to the increase of atmospheric pressure.

(vi) A student planted some seeds in sand. After the radical was fully developed, it was observed that in all seedlings it grew downward horizontally instead of vertically. This indicates that:

1. the sand contained water on one side only.
2. the sand contained large particles which prevented the radical to grow vertically.
3. the force of gravity forced the radical to grow horizontally.
4. it is the nature of radical to grow horizontally always.
5. the concentration of auxin inhibited the radical to grow vertically.

(vii) During the school race Mary experienced an increased rate in breathing.

This is because breathing rate supplies extra:

1. energy required by the active muscle.
2. oxygen required by the active muscle.
3. heat required by the active muscle.
4. enzymes required by the active muscles for respiration.
5. Work required by the muscles for faster running.

(viii)The best way of preventing viral infection is:

1. through biological control.
2. avoiding direct contact with an infected person.
3. killing all viruses.
4. vaccination.
5. by medical treatment.

(ix)Girls circumcision or female genital mutilation is considered to be a:

1. good sexual health practice because it controls prostitution among women.
2. good mental health practice.
3. bad physical harassment to women.
4. bad practice which interferes with sexual health.
5. good practice which prevents spread of HIV/AIDS.

(x)In green grass there are usually large numbers of green grasshoppers than brown grasshoppers. The best explanation is that the:

1. green grasshoppers feel the need of being green to give them protection.
2. predators do not capture green grasshoppers as frequently as brown grasshoppers.
3. green grass makes the brown grasshopper not to be seen by the predators.
4. green grasshoppers obtain enough food from green grass than brown grasshopper.
5. green grass stimulates green grsshoppers to reproduce and increase in number faster than brown grasshoppers.