Biology 2011 JAMB Past Questions - Question 43: If the cross of a red-flowered plant with a whiteflowered plant produces a pink-flowered plant, it is an example of

Correct Answer

D

Explanation

The first filial generation produces pink flowers only. Incomplete dominance is the ability of two contrastingalleles or genes that is red and white flowers to interact and (.roduce aheterozygous phentoype (pink flowers) that is different from the two homozygous phenotypes red flower and white flower respectively. Mutation is a sudden change in the genetic materials (the genes or chromosomes) of an organism resulting in the formation of new distinct and stable character on the body of the organism. Co-dominance occurs when- the alleles or genes in theheterozygous individual have equal strength or are fully expressed. The effect of each gene or allele is not modified by the presence of the other gene. Co-dominance is illustrated in the ABO blood system in which an individual with blood group ABhas two genes, A. and B with equal strength. He has red blood ceils that carry both antigens A and B on their surfaces. Linkage is the ability of two or more genes to segregate together in a genetic cross. These genes are located on the same chromosome and carry traits that stay together. This is illustrated using an insect Drosophila in which two characters namely black body colour and short wings are transmitted together.