Biology Past Questions And Answers
2401
Only specially adapted micro-organisms are found in
- A. salty water
- B. humid air
- C. moist soil
- D. mouth cavities
2402
Shrubs do not survive on newly weathered soils because
- A. the top soil is shallow
- B. drainage on such soil is poor
- C. humus is absent from the soil
- D. the soil tends to be sandy
2403
Salts and water are absorbed in the roots and transported to leaves by
- A. diffusion through the xylem tissues
- B. osmosis through the phloem tissues
- C. diffusion through the phloem tissues
- D. osmosis through the xylem tissues
2404
The significance of a very large number of termites involved in nuptial swarming is to
- A. provide birds with plenty of food
- B. ensure their perpetuation despite predatory pressure
- C. search for a favourable place to breed
- D. ensure that every individual gets a mate
2405
The sensory cell that responds to dim light is referred to as the
- A. cone
- B. lens
- C. rod
- D. iris
2406
Which of the following are consumers in these food chains?
- A. maize and rabbits
- B. chicken, rats and maize
- C. eagle, maize and snakes
- D. humans, eagle and snakes
2407
Which of the following is the least safe method of birth control? Using
- A. spermicide creams
- B. contraceptive pills
- C. barriers such as condoms
- D. the withdrawal method
2408
What is the primary source of variation in a population?
- A. Gene flow
- B. Mutation
- C. Natural selection
- D. Genetic drift
2409
The membrane surrounding the vacuole in a plant cell is called the
- A. plasmalemma
- B. tonoplast
- C. nuclear membrane
- D. endoplasmic reticulum
2410
The correct increasing order of size for the cell components responsible for heredity is
- A. chromosome → DNA → nucleus → gene
- B. DNA → gene → chromosome → nucleus
- C. chromosome → nucleus → DNA → gene
- D. DNA → gene → nucleus → chromosome