NE ADVANCED BIOLOGY SERIES TANZANIA 2025/2026
NE SUPER SERIES FORM SIX JOINT EXAMINATION
GENETICS: SOLVING QUESTIONS FORM SIX HOMEPACKAGE DECEMBER 2025
1. (a) (i) Give the characteristics of hereditary materials.
(ii) Biochemical analysis of a sample of DNA showed that, 33 percent of the nitrogenous
bases were guanine. Calculate the percentage of the bases in the sample which
should be adenine. Explain how you arrived at your answer.
(b) Two plants which are phenotypically similar may be genetically different. Explain.
(c) Briefly explain how variation caused by environment differs from those caused by
mutations.
2. (a) Briefly explain how the each of the following is brought about:
(i) Epistasis (iv) Klinefelter’s syndrome
(ii) Aneuploidy (v) Down’s syndrome
(iii) Turner’s syndrome
(b) (i) Explain using appropriate genetic symbols, the possible blood groups of children
whose parents are both heterozygous, the father being blood group A and the mother
B.
(ii) If these parents have non-identical twins, what is the probability that both twins
will have blood group A?
3. (a) (i) DNA is termed to be the most favorable genetic materials. Give four reasons.
(ii) Briefly explain the evidence to support the idea of hereditary material being located
in the nucleus. Give three points
(b) Explain how the formation of messenger ribonucleic acid take place during protein
synthesis.
4. (a) Read the following facts, and explain the corresponding feature of the genetic code:
(i) No sentence can be left unpunctuated, or its meaning is lost.
(ii) Sometimes, different words have similar meanings, although one word-one
meaning also applies.
(iii) Imagine a recipe book used by cooks worldwide, with slight variations in
rare cases.
(iv) Think of a lock that requires a combination of three numbers to open.
(b) Despite facing many challenges, Gregor Mendel made important discoveries that
earned him the title “Father of Genetics.” Explain six (06) successes of Mendel in the
field of genetics.
(c) Imagine a DNA molecule that produce a messenger RNA, which travels from the
nucleus to a ribosome in the cytoplasm for translation into a polypeptide. Describe
in detail how the ribosome facilitates this process (diagram is not necessary)
