In the context of environmental pollution, 'Minamata disease' in Japan was caused by the severe contamination of water with: MCQ with Answer and Explanation

Explanation:
Melanin pigment in the iris determines eye color. High melanin: brown; low melanin: blue/green. Hemoglobin is in blood, carotene in plants, rhodopsin in retina.

Explanation:
The bottleneck effect is a form of genetic drift that occurs when a population's size is drastically reduced for at least one generation due to a severe environmental event (like a natural disaster, disease, or overhunting). The surviving population is a random, small sample of the original, and its gene pool may not represent the original population's genetic diversity. This leads to a significant loss of genetic variation, making the population more vulnerable to future changes.

Explanation:
Incomplete dominance occurs when the phenotype of the heterozygote is an intermediate blend of the two homozygous phenotypes. In snapdragons, a cross between a homozygous red (RR) and homozygous white (rr) flower produces heterozygous pink (Rr) flowers. Neither allele is completely dominant over the other, resulting in a blended phenotype.