What is probability of homozygous individuals for both characters in ${\mathrm{F}}_2$ generation of a dihybrid cross?

1.  1/2

2.  3/4

3.  1/3

4.  1/4 

Choose correct option with respect to given figure for determination of sex by chromosomal differences.

1.  b after spermatogenesis forms only one type of gametes

2.  b & c represents same sex

3.  a, d are heterogametic

4.  Sex determination in d is similar to grasshopper 

Which one of the following statement is incorrect?

The figure below shows the chromosome segregation during germ cells formation with four stages labelled as (A), (B), (C) and (D). Select the right option giving all the four stages correctly identified

1.  (A) Interphase            (B) Metaphase-l
     (C) Telophase-l           (D) Anaphase-ll

2.  (A) ${\mathrm{G}}_1$                        (B) ${\mathrm{G}}_2$
     (C) Anaphase-l            (D) Anaphase-ll

3.  (A) ${\mathrm{G}}_1$                        (B) ${\mathrm{G}}_2$
     (C) Metaphase-l           (D) Anaphase-l

4.  (A) ${\mathrm{G}}_1$                         (B) ${\mathrm{G}}_2$
    (C) Anaphase-l              (D) Metaphase-ll

Males are heterogametic and females are homogametic in

1.  Human beings and birds

2.  Fruit fly and butter fly

3.  Grasshopper and cockroach

4.  Birds and silkworm 

Mendel's work on Pisum sativum shows that 
1.  Alleles show blending inheritance 
2. Equal proportion of F₁ resembled either of the two parents
3.  In a dissimilar pair of factors, members of the pair are codominant
4.  Genotype of F2 tall plant can be determined by cross with recessive parent

In the pedigree analysis, the meaning of the symbol  is 

1.  Still birth

2.  Dizygotic twin

3.  Mating between relatives

4.  Sex unspecified 

What is correct for AB blood group system?

a.  The effect of both alleles of a gene is equally expressed.

b.  Produces an intermediate phenotypic effect.

c.  The blending of both alleles occurs.

d.  There is no intermediate phenotypic effect.

1.  a, c, d

2.  a, b, c

3.  a, d

4.  b. c 

How many diseases in the list given below are Mendelian disorders?

1.  Four

2.  Five

3.  Six

4.  Seven 

Read the following four statements (A-D)

A.  The characters never blend in heterozygous condition.

B.  Change in a single base pair of DNA does not cause mutation.

C.  Cancer cells commonly show chromosomal aberrations.

D.  In chicken, sex chromosomes in males are ZW and in females are ZZ.

How many of the above statements is/are right?

1.  Two

2.  Three

3.  Four

4.  One