Cell & Fundamentals of Genetics and Hereditary Quiz

Which of the following statements about chromosomes is incorrect? A. Their number is the same in all living organisms. B. They are composed of DNA and proteins. C. They carry hereditary information. D. They are visible only during cell division.

1. A only
2. A and D only
3. B and C only
4. D only

Answer: (a) A only

The diagram given below shows the chromosomes in the nucleus of a cell before it divides by mitosis. After mitosis, two daughter cells are formed. Which diagram represents the chromosomes in the nucleus of one of the daughter cells after mitosis?

Answer: (b)

Imagine that a species has 8 chromosomes in its somatic cells. A scientist observes a cell of this species undergoing meiosis. What will be the chromosome number in each gamete after meiosis?

1. 8
2. 16
3. 2
4. 4

Answer: (d) 4

Mutations always lead to harmful changes in an organism's traits. Which of the following best evaluates this statement?

1. True, mutations always disrupt the organism's functioning.
2. True, but only in the case of inherited mutations.
3. False, mutations can be neutral, beneficial, or harmful.
4. False, as mutations only occur in non-coding regions of DNA.

Answer: (c) False, mutations can be neutral, beneficial, or harmful.

In an experiment, a student crossed a red flower plant (RR) with a white flower plant (rr). The offspring were all pink. What does this outcome suggest about the inheritance pattern?

1. Co-dominance
2. Incomplete dominance
3. Complete dominance
4. Sex-linked inheritance

Answer: (b) Incomplete dominance

In humans, blood type is determined by multiple alleles (A, B, O). A person with type AB blood inherits one allele from each parent. This inheritance pattern is an example of co-dominance, where both A and B alleles are equally expressed. Which of the following pairs of parents could produce a child with blood type AB? A. Type A and Type B B. Type AB and Type O C. Type O and Type O

1. A only
2. A and B only
3. B only
4. A, B and C

Answer: (a) A only

Vitamin D-resistant rickets (hypophosphatemia) is inherited as an X-linked dominant trait. If a man with hypophosphatemia has children with a healthy woman, which of the following would be true about their children? A. All daughters will inherit the disease. B. None of the sons will inherit the disease. C. Both sons and daughters have a 50% chance of inheriting the disease. D. None of the children will inherit the disease.

1. A only
2. A and B only
3. C only
4. D only

Answer: (b) A and B only

Match the evolutionary evidence with its description: Evidence Description A. Fossil records 1 Similar structures in embryos. B. Comparative anatomy 2 Distribution of species across continents. C. Embryology 3 Study of ancient organisms. D. Biogeography 4 Homologous and analogous organs.

1. A-2, B-1, C-3, D-4
2. A-4, B-2, C-3, D-1
3. A-3, B-4, C-1, D-2
4. A-1, B-3, C-4, D-2

Answer: (c) A-3, B-4, C-1, D-2

The graph below shows the survival rates of moths during the Industrial Revolution. Before the revolution, light-coloured moths were common due to their ability to blend with light tree bark. After pollution darkened the bark, dark-coloured moths became more common. Which mechanism is illustrated by this pattern?

1. Artificial selection
2. Directional selection
3. Stabilising selection
4. Genetic drift

Answer: (b) Directional selection

A scientist conducted an experiment where he introduced insects into a new environment with fewer predators. After 20 generations, the insects displayed brighter colours. What does this suggest?

1. Predators cause insects to change colour.
2. Insects evolved brighter colours to scare predators.
3. Environmental changes lead to random mutations.
4. Brighter colours are an adaptation for attracting mates.

Answer: (d) Brighter colours are an adaptation for attracting mates.