Govt Exams
Cross AA × Aa produces AA and Aa offspring only. Cystic fibrosis requires aa genotype, so probability is 0%.
Genetic drift causes random, unpredictable changes in allele frequencies, particularly significant in small isolated populations.
F1 is Rr (all round). F2: 1 RR : 2 Rr : 1 rr. Among round seeds (3 total), only 1 is homozygous RR, so 1/3.
3:1 ratio (75% yellow : 25% green) is characteristic of monohybrid cross between two heterozygotes (Yy × Yy).
Vestigial structures are anatomical remnants that indicate common ancestry with other organisms, supporting comparative morphology evidence.
Frequency of Aa = 2pq where p = 0.6 and q = 0.4; 2(0.6)(0.4) = 0.48
Man (IAIB) × Woman (ii) produces IAi (Group A) and IBi (Group B) offspring only. O group requires ii genotype.
Silent mutations occur in the third position of codons (wobble base), changing the DNA sequence but not the amino acid due to codon degeneracy.
Female XwXw × Male XWY produces: XWXw (red female), XwXw (white female), XWY (red male), XwY (white male). 50% of total offspring are white-eyed.
F1 (Tt) self-pollination gives 3 tall (TT, Tt, Tt) : 1 dwarf (tt) ratio following Mendelian monohybrid cross pattern.