Page 2 - HA

6. In human males all, the chromosomes are paired perfectly except one. This/these
unpaired chromosome is/are
(i) Large chromosome
(ii) Small chromosome
(iii) Y-chromosome
(iv) X-chromosome
a. (i) and (ii)
b. (iii) only
c. (iii) and (iv)
d. (ii) and (iv)
7. The maleness of a child is determined by
a. The X-chromosome in the zygote
b. The Y-chromosome in zygote
c. The cytoplasm of germ cell which determines the sex
d. Sex is determined by chance
8. A zygote which has an X-chromosome inherited from the father will develop into a
a. Boy
b. Girl
c. X-chromosome does not determine the sex of a child
d. Either boy or girl
9. In which of the following animals sex is genetically determined?
a. turtle
b. humans
c. snail
d. lizard

SUBJECTIVE

Q. Questions- Easy Marks Level
NO
1. What will be the sex of the offspring if a sperm carrying X – 1 E
Chromosome fertilizes the egg?
2. Name an environmental factor that determines sex of an 1 E
organism?
3. Mention two reasons why Mendel used pea plant for his 3 AV
hybridisation experiments.
4. a) In human beings, the statistical probability of getting either a 3 AV
male or a female child is 50:50. Give reasons and explain with the
help of diagram.
b) Name the unit of inheritance. What is its function?
5. a) Why are males called heterogametes? 3 D
b) In humans, genetically the sex of a new born child is
determined by the father and not by the mother.” Justify this
statement.
6. Trace the F1 generation formed by crossing two plants with 3 D
separate traits for shape and seed colour- round green (RRyy)
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