16. Which of the following is TRUE of the process of conjugation in Paramecium?
- A. Micronucleus disintegrates
- B. Each ex-conjugant divides only once
- C. Macro nucleus undergoes division
- D. Each micronucleus divides twice
17. People who suck petrol with their mouths run the risk of increasing in their blood the concentration of
- A. iron
- B. lead
- C. calcium
- D. magnesium
18. Which of the following is a measure for the control of bilharzia?
- A. Cutting low bushes around homes
- B. Application of molluscicides in water bodies
- C. Screening windows and doors with mosquito nets
- D. Application of herbicides in water bodies
19. The appendicular skeleton is composed of the pectoral girdle
- A. pelvic girdle, fore and hind limbs
- B. pelvic girdle and fore limbs
- C. lumbar vertebrae and pelvic girdle
- D. lumbar vertebrae, fore and hind limbs
20. A freshwater plant such as water lily can solve the problem of buoyancy by the possession of
- A. acrenchymarous tissues
- B. dissected leaves
- C. thin cell walls of the epidermis
- D. water-repelling epidermis
21. The correct sequence for the perception of smell in mammals is
- A. chemicals –> olfactory nerve endings –> brain
- A. dissolved chemicals –> sensory cells –> olfactory nerve –> brain
- B. dissolved chemicals –> nasal sensory cells –> brain
- C. chemicals –> mucus membrane sensory cells –> brain
22.
i. High birth rate and high immigration rate
ii. Low birth rate and high immigration rate
iii. Low mortality rate and low emigration rate
iv. High mortality rate and high emigration rate.
Which combination of the above can cause rapid over-crowding in climax biotic communities and human settlements?
- A. II and III
- B. I and III
- C. I and IV
- D. I and II
23. The number of plant species obtained from a population study of a garden is as follows: Guinea grass(15), Ipomoea spp(5), Sida spp (7) and Imperata spp (23)
What is the percentage of occurrence of Imperata spp?
- A. 35%
- B. 16%
- C. 46%
- D. 23%
24. When a marine fish was taken from the ocean and put in a tank of fresh water, it died after a short period because
- A. the tank was too small compared to the large-ocean
- B. the body cells of the fish swelled and burst as a result of the hypotonic fresh water
- C. the body cells of the fish shrank as their sap was hypertonic to the freshwater
- D. there was no food in the tank, so the fish starved
25. If a DNA strand has a base sequence TCA, its complementary strand must be
- A. ATG
- B. TAG
- C. GAT
- D. AGT
26. The two key cations involved in the action potential of nervous transmissions are
- A. Na+ and Fe2+
- B. Mg2+ and K+
- C. Na+ and K+
- D. Fe2+ and Mg2+
27. Ramis raffia. Il. Agama agarna III. Bufo regularis IV. Tilapia
The order of evolutionary advancement of the above vertebrates is
- A. I, II, III, IV
- B. I, IV, III, II
- C. II, III, IV, I
- D. IV, III, II, I
28. Which of the following produces both hormones and enzymes?
- A. Ileum
- B. Pancreas
- C. Gall bladder
- D. Kidney
29. The correct sequence of the movement of urea during urine formation is
- A. glomerulus —> Bowman’s capsule -> convoluted tubule —> Henle’s loop -> collecting- tubule
- B. glomerulus -> Bowman’s capsule -> convoluted tubule -> Henle’s loop -> convoluted tubule -> collecting tubule
- C. convoluted tubule -> glomerulus –> Nettle’s loop -> Bowman’s capsule->collecting tubule
- D. convoluted tubule -> Bowman’s capsule -> Henle’s loop -7> glomerulus -> collecting tubule
30. The order of passage of food in the digestive system is
- A. ileum –> caecum ->large intestine -> rectum
- B. ileum –> colon –> caecum -> rectum
- C. large intestine –> ileum -> caecum -> rectum
- D. colon -> caecum -> ileum -> rectum
