Blood group of a person is $A$ and he is suffering from albinism. What percentage of his gametes will have genotype $I^A a$?

The physical characteristics of an organism can be observed through its:

Choose the correct option for the given descriptions:
$(i)$ The heterozygous female transmits the disease to the son.
$(ii)$ Change in the shape of the $RBC$ from biconcave disc to elongated sickle-like structure.
$(iii)$ Mentally retarded.
$(iv)$ Haemoglobin is not formed in the proper amount in the blood.

The science which links heredity with environments is known as:

State how many of the given statements are correct.
$(1)$ In a dihybrid cross experiment,Mendel obtained a test cross ratio of $1:1:1:1$.
$(2)$ Coupling and repulsion were first explained by Bateson and Punnett.
$(3)$ Klinefelter syndrome is a sex-chromosomal disorder occurring in females.
$(4)$ Mendel selected $7$ pairs of contrasting traits in pea plants to explain his experiments.
$(5)$ The chromosomal theory of inheritance was first proposed by Sutton and Boveri.

Identify the incorrect statement from the following.