Genetics
Exercise 1 Solution A.1. d) Ascaris Solution A.2. a) 3 : 1 Solution B.1. (a) – (iii) Study of laws of inheritance of characters (b) – (v) Chromosomes other than the pair of sex chromosomes (c) – (iv) A gene that can express when only in a similar pair (d) – (ii) The alternative forms of a gene (e) – (i) Chromosomes similar in size and shape Solution B.2. Lion, tiger, domestic cat (Any two) Solution B.3. Colour-blindness, Thalassaemia, Sickle cell anaemia and Haemophilia (Any two) Solution B.4. Homozygous dominant – RR Homozygous recessive – rr Solution C.1. (a) Phenotype Genotype The observable Characteristic which is genetically controlled is called phenotype. The set of genes present in the cells of an organism is called its genotype. (b) Character Trait Any heritable feature is called a character. The alternative form of a character is called trait. (c) Monohybrid cross Dihybrid cross I