What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants?

(1) There is considerable genetic variation in garden peas.

(2) Traits are inherited in discrete units, and are not the results of ʺblending.ʺ

(3) Genes are composed of DNA.

(4) An organism that is homozygous for many recessive traits is at a disadvantage.

An organism with two copies of the same allele is:

Which of the following terms best describes when the phenotype of the heterozygote differs from the phenotypes of both homozygotes?

Today ________ are extensively used as a _______ point in the sequencing of whole genome

(1) Pedigree charts, conclusive

(2) Genetic maps, starting

(3) Pedigree charts, starting

(4) Genetic maps, conclusive

The initial studies for sex determination were done over

(1) Plants

(2) Insects

(3) Humans

(4) Hen

Which of the following statements are correct regarding Chromosomal basis of sex determination?

(i) The mechanism of sex determination in insects is of XO type.

(ii) XX insect is female while XO insect is male.

(iii) The X chromosome is called sex chromosome because it was involved in sex determination.

(iv) Grasshopper has XY type of sex determination.

(v) Man has XX type of sex determination.

(1) (iv), (v)

(2) (i), (ii), (iii), (iv), (v)

(3) (i), (ii), (iii)

(4) (i), (iv), (v)

Among human males _______ chromosome is present but its counterpart is _____ and called ______ chromosome.

(1) Y, bigger, Z

(2) X, smaller, Z

(3) X, smaller, Y

(4) Z, bigger, X

In which of the following male heterogamety is not observed?

(1) Insects

(2) Birds

(3) Humans

(4) (1) and (2)

Which of the following matches is wrong?

(1) Birds- ZZ(male)- ZW(female)

(2) Drosophila- XY(male)- XX(female)

(3) Humans- XY (male), XX (female)

(4) Cockroach- - XZ(male)- ZZ(female)

Which of the following statement is correct with respect to human sex determination?

(1) The genetic makeup of egg determines the sex of child.

(2) Female produces two types of ovums and males produce only one type of sperm.

(3) Each pregnancy has more probability of male child than of female.

(4) Out of 23 pairs of chromosomes, 22 are same both in males and females.