SAT – P1
Time: 30 min. Topic: one gene inheritance
1) If the offspring is aa, what possible combinations of parental genotype would have
produced these progenies?
(A) AA and aa
(B) AA and Aa
(C) Aa and AA
(D) Aa and Aa
2) A pea plant parent having violet-coloured flowers with unknown genotype was crossed
with a plant having white-coloured flowers. In the progeny, 50% were white. The
genotypic constitution of the parent having violet-coloured flowers was
(A) Homozygous
(B) Merozygous
(C) Heterozygous
(D) Hemizygous
3) In case of incomplete dominance what ratios of genotype and phenotype do we obtain
(A) 1:2:1 and 3:1 respectively
(B) 3:1 and 1:2:1 respectively
(C) 3:1 genotypic and phenotypic
(D) 1:2:1 genotypic and phenotypic
4) Identify the incorrect statement about “law of segregation”:
A) Only one alle is transmitted to a gamete
B) The segregation of alleles is random process
C) Tall parent produces pure gametes and dwarf parent produce impure gametes
D) Gametes will always be pure for trait
5) Which of the following trait in the garden pea plant would express itself only in
homozygous condition?
(A) Violet colour flower
(B) Terminal flower position
(C) Green pod colour
(D) Yellow seed colour
6) In monohybrid cross F1 progeny resemble neither of parents. What will be true in this
case?
(A) The parental trait would not appear in the F2 progenies
(B) The F2 phenotypic ratio will be different from the F2 genotypic ratio
(C) It could be in case of incomplete dominance
(D) The F2 phenotype ratio will be similar to any mendelian monohybrid cross
7) The cross between tall and dwarf parent was performed and 120 offspring were
produced in which 90 plants were tall and 30 were dwarf. Find out the genotype of their
parents
(A) Tt and TT
(B) Tt and Tt
(C) TT and tt
(D) Tt and tt
8) In pea plant, yellow seeds are dominant to green. If heterozygous yellow seeded plant,
what ratio of yellow and green plants would you expect in F1 generation?
(A) 50 : 50
(B) 9 : 1
(C) 1 : 3
(D) 3 : 1
9) In Mendel’s experiments, the contrasting traits did not show blending in:
(A) F1 stage
(B) F2 stage
(C) Both F1 and F2 stages
(D) The statement is false as blending was seen at all stages
10) Monohybrid cross is defined as
(A) Cross between plants differing in one chromosome
(B) Cross between plant differing in one character only
(C) Cross between plant differing in two traits
(D) All of the above
11) Heterozygous plant produces:
(A) Only one kind of gamete
(B) Two kind of gametes each having one allele with equal proportion
(C) Two kind of gametes each having two alleles in equal proportion
(D) Two kind of gametes each having one allele occurring in more gametes than the other
12) Which mathematical expression can be used to obtain the genotypic ratio of F2
offsprings from the gametes of the F1 progeny?
(A) Monomial expression
(B) Binomial expression
(C) Trinomial expression
(D) Algebraic expression
13) What does the second law of Mendel state?
(A) Factors occur in pairs
(B) The alleles separate during meiosis and pair up during fertilization
(C) One factor is dominant over the other
(D) Factors determine the characters of the offspring’s
14) Self-crossing of dwarf plants from F2 generation will produce _____
(A) 100% tall and 0% dwarf plants
(B) 0% tall and 100% dwarf plants
(C) 50% tall and 50% dwarf plants
(D) 25% tall and 75% dwarf plants
15) In chickens, the allele for a pea comb (A) is dominant to the allele for a single comb (a).
A mother with the genotype Aa and a father with the genotype Aa produces an offspring.
What is the percent chance that the offspring will have a single comb?
(A) 0%
(B) 25%
(C) 75%
(D) 50%
16) Ability of gene to have multiple phenotypic effects is known as
(A) Co-dominance
(B) Pleiotropy
(C) Multiple allelism
(D) Incomplete dominance
17) The best examples of pleiotropy are
(A) Skin colour in humans and colour blindness
(B) Phenylketonuria and starch synthesis in pea
(C) Starch synthesis in pea and ABO blood grouping
(D) Phenylketonuria and ABO blood grouping
18) Read the following statements for ABO blood grouping carefully and find out how many
of them are correct:
i) It is a good example for co-dominance where IA and Io are co-dominant alleles
ii) Chance of obtaining child with genotype IAIB is 0% is the father and mother have
genotype IAIO and IOIO respectively
iii) In ABO blood grouping IO is recessive allele
iv) Six phenotypes and four genotypes are obtained from combinations of IA, IB and IO
(A) 2
(B) 3
(C) 1
(D) 4
19) Underlying cause of pleiotropy is
(A) Incomplete dominance
(B) Segregation of alleles in gamete
(C) Metabolic pathway which contributes towards different phenotypes
(D) Expression of only one trait by one gene
20) A wife had genotype IAIB than what is the probability of husband having genotype IAIO, if
his mother and father had genotype IAIA and IBIO
(A) 50%
(B) 25%
(C) 75%
(D) 0%
21) What is Mendel’s first law
(A) Law of independent assortment
(B) Law of segregation
(C) Law of dominance
(D) Law of purity of gametes
22) When a gene controls more than one phenotype
(A) Gene shows dominance of for all phenotypes
(B) Dominance is a autonomous feature of a gene and its product
(C) Dominance is not a feature of a gene but is a feature of product for which it has
information
(D) Dominance depends up on gene product and particular phenotype we choose to
examine
23) The gene for starch synthesis showed
(A) Incomplete Dominance in case of seed shape and dominance for seed size
(B) Pleiotropy but not dominance
(C) Phenotypic ratio for seed shapes as 3:1 and for seed size as 1:2:1
(D) C0-dominance
24) --------------------- pairs of contrasting traits were studied by Mendel in pea plant
(A) 6
(B) 7
(C) 14
(D) 10
25) Which of the following characters was not chosen by Mendel
(A) Pod shape
(B) Pod colour
(C) Location of flower
(D) Pod length
26) What can be the blood group of offspring when both parents have AB blood group?
(A) AB only
(B) A, B and AB
(C) A, B, AB and O
(D) A and B only
27) ABO blood grouping in human beings cites the example of
(A) Incomplete dominance
(B) Co-dominance
(C) Multiple allelism
(D) Both (B) and (C)
28) Which of the following are reasons for Mendel’s success:
(i) Usage of true breeding pea varieties
(ii) Consideration of one character at a time
(iii) Maintenance of statistical records of experiments
(iv) Knowledge of linkage and incomplete dominance
(A) (i) and (ii) only
(B) (i), (ii) and (iii)
(C) (i) and (iv) only
(D) (i), (iii) and (iv)
29) Mendel formulated law of purity of gametes on the basis of
(A) Monohybrid cross
(B) Dihybrid cross
(C) Test cross
(D) Back cross
30) Unmodified allele of an enzyme coding gene may be responsible for production of
(A) The normal/less functional enzyme
(B) A functional enzyme
(C) A non-functional enzyme
(D) No enzyme at all
