Principles of I...

Genes for autosomal dominant traits are located on the autosomes. The traits are expressed even when they are present in heterozygous conditions.

Which one of the following autosomal dominant traits (diseases) has been found to be inheritable?

Sickle-cell anaemia is caused by the change of amino acid glutamic acid by valine at the sixth position of the beta globin chain of haemoglobin. The change of amino acid occurs due to which of the following phenomenon in which the sixth codon of beta globin gene is transformed from GAG to GUG?

Alkaptonuria is an inborn metabolic disorder resulting from the lack of which of the following enzymes?

Which of the following cases of marriage will produce 50% colour-blind sons and 50% carrier daughters and also, the pattern of criss-cross inheritance is noted?

Klinefelter's syndrome is an aneuploid condition, where the individual is characterised by ___________ genotype.

Assertion: Human skin colour has continuous variations.
Reason: It is a polygenic trait with additive effect.

Red coloured four-o'clock plant is crossed with a white one. The resultant offspring is pink. It is an example of

When one gene in its epistatic state masks the expression of other dominant gene present on different locus, it is called recessive epistasis. Its modified F₂ phenotypic ratio will be

In sweet pea, cross between two white parents produces purple progeny due to

Which of the following statement(s) is/are incorrect in relation to the chromosome theory of inheritance?
a. According to this theory, gametes are the carriers of genetic material or physical units of heredity.
b. Chromosomes undergo segregation and independent assortment during meiosis.
c. The chromosomes recombine during fertilisation to form zygote.