A man can inherit his $X-$chromosome from his
Maternal grandmother or maternal grandfather
Father
Maternal grandfather
Paternal grandfather
Select the correct statement:
Marriages between close relatives and cousins is not advisable because
Choose correct answer :
$(i)$ Queen Elizabeth shows a number of haemophilic descendents.
$(ii)$ Variation in blood group prevalences due to incomplete dominance.
$(iii)$ Drosophila has three pairs of autosomal chromosomes.
$(iv)$ In birds, female is heterozygous.
Select incorrect statement
$(A)$ Linked genes cause absolute lethality
$(B)$ Persons affected by $PKU$ do not show mental disorder
$(C)$ $F_{2}$ ratio in codominance and incomplete dominance are same
$(D)$ Sex of male Drosophila is dependent on $Y-$chromosome
Match the terms in column $I$ with their description in column $II$ and choose the correct option.
Column $-I$ | Column $-II$ |
$(A)$ Dominance | $(i)$ Many genesgovern a single character |
$(B)$ Codominance | $(ii)$ In a heterozygousorganism only one allele expresses itself |
$(C)$ Pleiotropy | $(iii)$ In a heterozygousorganism both alleles express themselves fully |
$(D)$ Polygenic | $(iv)$ A single gene inheritanceinfluences many characters |