2021 WAEC Biology Question And Answer

2021 WAEC Biology Questions And

Answers Biology question and answer essay and objective. 1-10: BCDDCDCBCA 11-20: AACCCACDAA 21-30: CDBDACCCAA 31-40: ABBCABBCBD 41-50: DBDABDCCDD (1ai) When the head moves or changes position,the endolymph fluid in the semi-cricular canals moves and stimulates the nerve endings. The nerve endings then transmit the impulses through vestibular to the cerebellum of the brain where the new position at the head is interpreted and the appropriate responses sent to the muscular system to maintain body balance. (1aii) (1aiii) The middle ear in human can be split into three parts; external, mdiddle and inner. The middle ear lies within the temporal bone, and extends from the tympanic membrane to the lateral wall of the inner ear. The main function of the middle ear is to transmit vibrations from the tympanic membrane to the inner ear via the auditory ossicles. 6ai) External fertilization is a mode of reproduction in which a male organism’s sperm fertilizes a female organism’s egg outside of the female’s body. (6aii) Internal fertilization occurs most often in landbased animals, although some aquatic animals also use this method. There are three ways that offspring are produced following internal fertilization. 6bi) (i)Toad (ii)Frog (6bii) (i)Goat (ii)Cow (6ci) (i)the foetus will not get oxygen (ii)the foetus will not get nutrients. (iii)waste products from your baby’s blood will not be removed (6cii) (i)fundus (ii)corpus (iii)isthmus (iv)cervix. 38, 39. Two conscious patient X and Y whose blood group genotypes are AO and AB respectively were transfused with blood from the same donor. Patient X immediately showed signs of difficulty in breathing while patient Y showed no negative reaction. 38. Patient X and Y were likely transfused with blood of genotype A. OO B. AO C.BO D. AA 39. What should the hospital have done to prevent patient X from showing the symptom described above? Patient X should have A. Undergone an agglutination test B. Been asked for the blood group. C. Been screened for HIV D. Undergone malaria test. 40. The greatest contribution to genetic studies was made by A. Gregor Mendel B. Thomas Morgan C. Charles Darwin D. Robert Hooke. 41. The exchange of genes between homologous chromosomes is called A. Crossing over B. Back cross C. Test cross D. Mutation The diagrams below are illustration of the inheritance of coat in mice. J, K, L, M and N are parents. The crosses between two parent mice gave rise to offspring P, Q, R and S. study the diagram and answer question 42 and 43 More answers loading. Keep refreshing this page and bookmark for latest updates.