CBSE Class 10 Science Heredity and Evolution MCQs Set B

Question : Which one of the following is not one of the direct conclusions that can be drawm from Mendel’s experiment?
a) Only one parental trait is expressed
b) Two copies of each trait is inherited in sexually reproducing orgainsm
c) For recessive trait to be expressed, both copies should be identical.
d) Natural selection can alter frequency of an inherited trait.
Answer : D

Question : A section of DNA providing information for one protein is called—
a) Nucleus
b) Chromosomes
c) Trait
d) Gene
Answer : D

Question : Which one of the following is present in the nucleus?
a) Gene
b) DNA
c) Chromosomes
d) All of these
Answer : D

Question : What is the probability that a human progeny will be a boy?
a) 50%
b) 56%
c) 47.34%
d) It varies
Answer : A

Question : There is an inbuilt tendency of variation during reproduction because of–
(i) Errors in DNA copying
(ii) Sexual reproduction
a) only (i)
b) only (ii)
c) both (i) and (ii)
d) none of them
Answer : B

Question : If we breed a group of squirrels and surgically remove their tails, then amongst the progeny of these tailless squirrels–
a) All have no tail
b) All have a tail
c) Some of them have tails
d) Cannot be determined.
Answer : B

Question : Formation of 2 independent species due to genetic drift, geographical isolation, natural selection is specifically referred as–
a) Evolution
b) Classification
c) Speciation
d) Reproduction
Answer : C

Question : If A and B have n characteristics common while A and C have n/2 characteristics common, then which of the two organisms are more closely related?
a) A and C
b) A and B
c) Characteristics need to be known
d) None of these
Answer : C

Question : Analogous organs have
a) Same structure, same function
b) Different structure, different function
c) Same structure, different function
d) Same function, different structure
Answer : D

Question : How can we know how old fossils are:
a) Fossils found closer to surface are recent than those found much below
b) Detecting ratios of isotopes
c) Studying its characteristics
d) All of these
Answer : D

Question : Wild cabbage is being cultivated for thousands of years and humans have generated broccoli, cauliflower, kala etc. from it. This is an example of
a) Natural selection
b) Genetic drift
c) Geographic isolation
d) Artificial selection
Answer : D

Case study questions

I Read the given information and answer the following questions.

Sahil performed an experiment to study inheritance pattern of genes. He crossed tall pea plants (TT) with short pea plants (tt) and obtained all tall plants in F1 generation.

Question : What will be the set of genes present in F1 generation?
Answer : Tt

Question : Give reason why only tall plants are observed in F1 progeny.
Answer : Tallness is a dominant character and dwarfness is a recessive character.

Question : When F1 plants were self pollinated, a total of 800 plants produced. How many of these would be tall, medium height or short plants? Give the genotype of F2 generation.
Answer : Out of 800 plants 600 plants will be tall and 200 plants will be small, 1 TT: 2Tt: 1tt