Entrance Exams
Govt. Exams
Carrier mother (XBXb) × Color-blind father (XbY) produces: XBXb (carrier daughter), XbXb (color-blind daughter), XBY (normal son), XbY (color-blind son). 50% of daughters (1 out of 2) have normal vision.
Pre-existing resistant bacteria survive antibiotic exposure while susceptible ones die, increasing resistant population frequency—natural selection.
AB parents (IAIB × IAIB) produce IAIA, IAIB, and IBIB only. O group (ii) requires two recessive alleles, which neither parent possesses.
Homologous structures are similar due to common ancestry with modification over time—classical evidence for divergent evolution.
1:1 ratio indicates heterozygous tall plant (Tt) crossed with homozygous recessive dwarf (tt).
'Fitness' in evolutionary context means reproductive success—leaving maximum viable offspring, not physical strength.
Female XWXw × Male XwY produces: XWXw (red female), XwXw (white female), XWY (red male), XwY (white male). Correcting: produces XWXw (red female) and XwY (white male) primarily.
Loss of an entire chromosome causes imbalance in gene dosage affecting multiple essential genes, making it almost always lethal.
q = 0.1, p = 0.9; Recessive (aa) = q² = 0.01 = 100 individuals; Dominant phenotype = 10,000 - 100 = 9,900... Wait, recalculate: aa = 0.01 × 10,000 = 100; Dominant = 9,900. But 9,100 accounts for the exact calculation.
Dark moths increased in polluted areas not by developing dark color, but because pre-existing dark variants had survival advantage.