(a) always since it is a mutation
(b) in heterozygous condition
(c) neither in homozygous nor in heterozygous condition
(d) in homozygous condition.
Answer : D
Question. XX-XO type of sex determination and XX-XY type of sex determination are the examples of
(a) male heterogamety
(b) female heterogamety
(c) male homogamety
(d) both (b) and (c).
Answer : A
Question. A plant bearing purple flowers (RR) was cross pollinated with a plant bearing white flowers (rr). What would be the ratio of the plants bearing white flowers and purple flowers respectively in F2 generation when the F1 progeny were self pollinated?
(a) 1 : 3
(b) 3 : 1
(c) 1 : 1
(d) 2 : 1
Answer : A
Question. In a dihybrid cross four phenotypes form in the ratio of 9 : 3 : 3 : 1, because of
(a) dominance of one phenotype in each pair ofcontrasting traits
(b) independent assortment of the genes of contrasting traits
(c) crossing over of genes
(d) mixed effect of dominance and independent assortment.
Answer : B
Question. Some of the dominant traits studied by Mendel were
(a) round seed shape, green seed colour and axial flower position
(b) terminal flower position, green pod colour and inflated pod shape
(c) violet flower colour, green pod colour and round seed shape
(d) wrinkled seed shape, yellow pod colour and axial flower position.
Answer : C
Question. Why were pea plants more suitable than dogs for Mendel’s experiments ?
(a) There were no pedigree records of dogs.
(b) Pea plants can be self-fertilised.
(c) All pea plants have only two chromosomes.
(d) Dogs have many genetic traits.
Answer : B
Question. Select the incorrect statement.
(a) In male grasshoppers, 50% of sperms have no sex chromosome.
(b) Female fruitfly is heterogametic.
(c) Human male produces two types of sperms 50% having X chromosome and 50% having Y chromosomes.
(d) In turtle, sex determination is regulated by environmental factors.
Answer : B
Question. Mendel conducted his famous breeding experiments by working on
(a) Drosophila
(b) Pisum sativum
(c) Escherichia coli
(d) all of these.
Answer : B
Question. The genotypic ratio in F2 generation of monohybrid cross will be
(a) 1 : 2 : 1
(b) 3 : 1
(c) 1 : 1
(d) 1 : 2.
Answer : A
Question. The main reason for Mendel’s success in discovering the principles of inheritance was
(a) he considered each character separately
(b) he was lucky not to encounter with linkage problem
(c) the plant was pure breeding
(d) all of these.
Answer : D
Assertion & Reasoning Based MCQs
(a) Both assertion and reason are true, and reason is correct explanation of the assertion.
(b) Both assertion and reason are true, but reason is not the correct explanation of the assertion.
(c) Assertion is true, but reason is false.
(d) Assertion is false, but reason is true.
Question. Assertion : Test cross is a back cross.
Reason : In test cross, individual is crossed with recessive parent.
Answer : B
Question. Assertion : The principle of segregation given by Mendel is the principle of purity of gametes.
Reason : Gametes are pure for a character and do not mix up.
Answer : A
Question. Assertion : In grasshoppers, females are heterogametic and males are homogametic.
Reason : In grasshoppers, male has only one sex chromosome (XO) whereas the female has sex chromosomes (XX).
Answer : D
Question. Assertion : Pure lines are called true breeds.
Reason : True breeds are used for cross breeding.
Answer : B
Question. Assertion : If mother is homozygous for black hair and father has red hair then their child can inherit black hair.
Reason : Gene for black hair is recessive to gene for red hair in humans.
Answer : C
Question. Assertion : A child which has inherited X chromosome from father will develop into a girl child.
Reason : Girl child inherits X chromosome from father and Y chromosome from mother.
Answer : C
Question. Assertion : In a monohybrid cross, offspring of F1 generation express dominant character.
Reason : Dominance occurs only in heterozygous state.
Answer : C
Question. Assertion: The traits that are obtained from parents are inherited traits.
Reason : These traits were developed in the parents during their lifetime.
Answer : C
Question. Assertion : If blood group of both mother and father is ‘O’ then the blood group of children will also be O.
Reason : Blood group in humans is determined by many alleles of a gene viz. IA, IB, IO.
Answer : B
Question. Assertion : Mendel successfully postulated laws of heredity.
Reason : He recorded and analysed results of breeding experiments quantitatively.
Answer : A
Very Short Answers
Short Answers
If centre of population contributes more then equilibrium is maintained while if extremes of population work then two peaks in the distribution of a trait produced, while former is disruptive selection.
Long Answers
Answer : It depends on our perspective through which we try to evaluate evolution. If complexity in body design is the parameter to define evolution, then human beings are more evolved than bacteria. Human beings are multicellular with organ system level of organisation whereas bacteria is unicellular and show cellular level of organization. In terms of complexity human beings are definitely highly evolved compared to bacteria.
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