NEET Zoology - MCQ Practice Questions

Gene flow between two populations can prevent genetic drift from causing fixation of alleles because:

A three-point testcross in Drosophila yields recombinant classes with lower frequencies than parental classes. This demonstrates:

A lethal allele that causes embryonic death in homozygous condition would alter the expected dihybrid ratio from 9:3:3:1 to:

In humans, if both parents are heterozygous carriers of sickle cell anemia (HbAS), what is the probability of their child being completely unaffected?

The concept of 'adaptive radiation' is best exemplified by:

A population experiences a bottleneck reducing its size from 10,000 to 100 individuals. Which evolutionary consequence is MOST likely?

In a X-linked trait, if the allele frequency of the recessive allele in males is 0.1, what is the allele frequency of the recessive allele in females at Hardy-Weinberg equilibrium?

A mutation changes a GC base pair to AT in a non-coding region of DNA. This mutation's evolutionary significance depends primarily on:

Which of the following best describes the Hardy-Weinberg equilibrium principle?

In a dihybrid cross between AaBb × AaBb, what is the probability of obtaining aabb genotype?

Which type of natural selection favors both extreme phenotypes over the intermediate phenotype?

What is the term for the evolutionary relationship where two or more species share a common ancestor?

In a test cross with a heterozygous individual (Aa), if 40% of offspring show the dominant phenotype, what might this indicate?

Which of the following represents the correct sequence of speciation in peripatric speciation?

A recessive genetic disorder appears in 1% of a population. What is the frequency of the recessive allele (q)?

Which mechanism of evolution is most likely responsible for the loss of eyes in blind cave fish?

In Drosophila, if the coefficient of inbreeding (F) increases, what is the expected change in heterozygosity?

A population of beetles shows industrial melanism. Dark beetles increased from 5% to 95% in 50 years in polluted areas. What type of selection is most likely operating?

Which statement about mutations is correct?

In a population, the allele frequency of 'a' is 0.4 and 'A' is 0.6. If the population is in Hardy-Weinberg equilibrium, what is the expected frequency of heterozygotes?