Carefully study specimens J and K and answer questions 4(a) to 4(d).
(a) Name the type of refuse in specimens: (i) J (ii) K.
(b) List three animal vectors of disease causing organisms that breed on a each of specimens J ana K.
(ii) Name four diseases each caused by animal vectors associated with each or specimen J and K.
(c) Name one method of disposal of each of specimens J and K in: (i) rural areas (ii) urban areas.
(d)(i)State four effects of improper disposal of specimen K
(ii) In a tabular form. state five differences between specimens J and K.
(iii) outline one way in which specimen J is of importance to farmers.
Study carefully specimen E and F and use them to answer questions 2(a) to 2(d).
(a) (i) What class of organism do specimen E and F belong to?
(ii) State three similarities between specimen E and F.
(iii) In a tabular form, state three differences between specimens E and F;
(b) State two ways each in which: (i) Specimen E (ii) Specimen F are of economic importance.
(C)(i) State one observable feature each of specimens E and F and how these features adapt the specimens against predation.
(ii) Name the habitats of specimens E and F.
(d) Remove all the wings of specimen E. Make a drawing 8-10 cm long of the dorsal view of specimen E and label fully.
(a) Study carefully specimens A, B, C, and D. copy and complete the table below
| Specimen | Part modified to form specimen | Mode of propagation | Stored material |
| A | |||
| B | |||
| C | |||
| D |
(b) In a tabular form state four observable differences between specimens A and C.
(c) Crush a small portion of specimen D and divide it into three equal parts. (i) Place a portion on a white tile and add two (2) drops of iodine solution.
(ii) Place another portion in a test tube and add one (1) ml of distilled water and shake. Add few drops of sodium hydroxide solution and shake again. Slowly add a few drop of 1% Copper (ii) sulphate solution. (iii) Smear the third part on a filter paper, leave for about five (5) minutes and observe carefully
(a) Explain the following terms:
(i) putrefaction
(ii) nitrogen fixation
(iii) nitrification
(iv) denitrification
(b) State three differences between nitrogen fixation and denitrification.
(c) Explain how nitrogen from urine gets to the roots of plants. W
(a) (i) What is the difference between the genotype and phenotype of an individual?
(ii) State two factors each which determine each of the terms in (a)(i).
(b) In a breeding experiment, a homozygous dog (BB) was crossed with a homozygous white dog (bb) to produce black puppies in the first filial generation (F1) The second filial generation produced a total of two hundred and forty (240) black and white puppies. With the aid of a genetic diagram, determine:
(i) the number of white puppies
(ii) the number of black puppies in the second filial generation.
(a)State the second law of thermodynamics.
(ii) Use the second law of thermodynamics to explain the flow of energy across different trophic levels in a food chain.
(b) (I) State three factors that can likely limit the size of human populations.
(ii) Outline two ways each by which humans can overcome the factors named in (b)(i).
(a) Make a diagram 8 — 10 cm long to show the relative position of the following organs in the mammalian gut:
(i) stomach
(ii) pancreas
(iii) liver
(iv) gall bladder
(v) duodenum and label fully.
(b) (i) List two diseases of the liver.
(ii) State five effects of the diseases in (b) (i) on the human body.
(c) State the deficiency symptoms of the following vitamins:
(i) vitamin A
(ii) vitamin C
(ii) Vitamin K;
(a) (i) What is the effect of gravity on plant growth?
(ii) Describe an experiment to demonstrate the effect of gravity on the roots of plants.
(b) Explain how bitter taste is detected in humans.
(c) Copy and complete the table below on endocrine glands and their functions.
| S/N | Endocrine glands | Hormone produced | functions |
| 1 | Thyroid | ||
| 2 | Insulin | ||
| 3 | Development of secondary sexual characters of females |
Adenine pairs with thymine because
- A. the two occur in the same nucleic acid
- B. one is a strong base and the other a weak base
- C. two purine bases easily pair up
- D. one is a purine base and the other a pyrimidine.
A vestigial structure in humans is
- A. earlobe
- B. toe bone
- C. tail bone
- D. spleen
Which of the following components of Larmark’s theory of evolution is considered faulty?
- A. Individuals of the same species growing under different environmental conditions differ from each other
- B. Use of certain organs result in development of those parts
- C. Unused organs degenerate
- D. Changes that result in individuals of the same species are transmitted to offspring
Natural selection is a consequence of
- A. distribution of organisms
- B. adverse conditions
- C. variation in organisms
- D. inbreeding
A man with blood group It IA IA is married to a woman with blood group IA IO. The blood group of their son is likely to be
- A. A
- B. O
- C. B
- D. AB
What is the probability? of a man of blood group AB married to a woman of blood group O producing a child of blood group O?
- A. 0%
- B. 25%
- C. 50%
- D. 75%
If a person has two alleles of the sickle cell anaemia gene, the person
- A. is a heterozygous carrier of the disease
- B. is immune to the disease and cannot pass it on to an offspring
- C. has the disease
- D. is probably of Asian ancestry
Which of the following statements best describes protein synthesis?
- A. DNA is directly involved in translation
- B. translocation oft e ribosomes exposes a new codon for base pairing with an amino acid
- C. Each tRNA with a particular anticodon always carries a different protein in the process
- D. One amino acid is always carried by more than one
Differences in characteristics observed between individuals of the same species is known as
- A. trait
- B. phenotype
- C. mutation
- D. variation
Acquired characters are
- A. received from parents
- B. passed to offspring
- C. caused by the environment
- D. caused by mutation
Which of the following statements is not true about continuous variation? It
- A. is usually controlled by several genes
- B. can be influenced by environmental factors
- C. follows a normal distribution curve
- D. is usually controlled by one or two pair(s) of genes
Which of the following activities promotes forest conservation?
- A. Lumbering
- B. Use of firewood for cooking
- C. Afforestation
- D. Production of paper
Which of the following practices improves crop yield in a clayey soil? Addition of
- A. more water and humus
- B. lime and humus
- C. fertilizers
- D. weedicides and fertilizers