1. The maleness of a child is determined by ?

sex is determined by chance

the cytoplasm of germ cell which determines the sex

the Y chromosome in zygote

the X chromosome in the zygote

Answer: the Y chromosome in zygote

Explanation:


2. The number of pair (s) of sex chromosomes in the zygote of humans is ?

Two

Four

One

Three

Answer: One

Explanation:

The number of sex chromosomes in the zygote of humans is one pair. It is not always a perfect pair. In females, it is perfect with two X-chromosomes. However, in males, there is one X-chromosome and one Y-chromosome.


3. The two versions of a trait (character) which are brought in by the male and female gametes are situated on ?

Sex chromosomes

Any chromosome

Two different chromosomes

Copies of the same chromosome

Answer: Copies of the same chromosome

Explanation:

The two versions of a trait a sweet situated on copies of same chromosome. Each parent contributes one copy of the gene for a particular character. In the gamete however, only one copy is present due to reduction division. At the time of fusion, the diploid condition is maintained. Sex chromosomes carry genes for sexual characters.


4. Genotype means ?

Genetic composition of an organ

Genetic composition of the individual

Genetic composition of plastids

Genetic composition of the germ cell

Answer: Genetic composition of the individual

Explanation:


5. The crossing of a homozygous tall plant with a dwarf would yield F plants in the ratio of ?

all homozygous dwarf

all homozygous tall

one homozygous tall, one homozygous dwarf and two heterozygous tall

two tall and two dwarf

Answer: one homozygous tall, one homozygous dwarf and two heterozygous tall

Explanation:


6. The genotype of a dominant parent is determined by crossing it with the recessive parent. This cross is called ?

out cross

long cross

back cross

test cross

Answer: test cross

Explanation:


7. Mendel's laws apply only when ?

First pair of contrasting character is dependent upon other pairs

Parents are pure breeding

The character are linked

F in monohybrid cross shows two types of individuals

Answer: Parents are pure breeding

Explanation:


8. Mendel conducted his hybridisation experiment with ?

Pigeon pea

Wild pea

Chick pea

Garden pea

Answer: Garden pea

Explanation:


9. Which of the following may be used to obtain an F2 generation ?

Cross-pollinating two parent plants

Cross-pollinating an F1 plant with a parent plant

Allowing flowers on a parent plant to be self-pollinated

Allowing flowers on an F1 plant to be self-pollinated

Answer: Allowing flowers on a parent plant to be self-pollinated

Explanation:

F2 generation can be obtained by allowing flowers on the plants of F1 generation to be self-pollinated.


10. Some dinosaurs had feathers although they could not fly but birds have feathers that help them to fly. In the context of evolution this means that ?

birds have evolved from reptiles.

reptiles have evolved from birds

feathers are homologous structures in both the organisms

there is no evolutionary connection between reptiles and birds

Answer: birds have evolved from reptiles.

Explanation: