Question 1
What is meant by the term sex linkage
Answer
These are genes located on the sex chromosomes and are transmitted together with those determine sex.
Question 2.
Part of one strand of DNA molecule was found to have the following sequence
G-C-C- G – A – T- T – T – A – C – G – G
What is the sequence
(i) of the complimentary DNA strand?
(ii) On a m-RNA strand copied from this DNA portion?
Answer
(i) C – G – G – C – T – A – A – A – T – G – C – C
(ii) C – G – G – C – U – A – A – A – U – G – C – C
(ii) C – G – G – C – U – A – A – A – U – G – C – C
Question 3
State three regions ion a plant where the end products of photosynthesis are translocated to?
Answer
- The growing and developing regions such as shoots, leaves, flowers, fruits and roots
- Storage organs or tissues such as tubers, corns, bulbs, rhizomes and seeds.
- The secretors organs such as nectar glands in some insect pollinated plants such as bananas
- Storage organs or tissues such as tubers, corns, bulbs, rhizomes and seeds.
- The secretors organs such as nectar glands in some insect pollinated plants such as bananas
Question 4
With reference to circulatory system only give two reasons why birds and mammals are more active compared to other organisms?
Answer
(i) Deoxygenated and oxygenated blood do not mix
(ii) Blood is at a higher pressure once the heart pumps it twice
(ii) Blood is at a higher pressure once the heart pumps it twice
Question 5
(a) What three characteristics are used to divide the phylum arthopoda into classes?
(b) The diagram below shows an organisms from a division in Kingdom plantae. Study it and answer the questions that follow
(i) Identify the division from which the plant was obtained
(ii) Name the parts labelled X and Z
Answer
(a)
- - Number of limbs
- Presence and number of antennae
- Number of body parts
- i) Bryophyta
- ii) X – Seta
Z – Rhizoid.