ABO blood group character in human population exhibits four possible phenotypes and six different genotypes. Explain the different mechanisms of inheritance involved in exhibiting the possibility of four phenotypes and six genotypes.

Study the pedigree chart given below showing the inheritance pattern of a human trait and answer the questions that follow:

(a) Is the trait autosomal dominant or recessive or sex-linked? Why?
(b) Give the genotypes of the parents in generation I and of the son in generation II.
(c) Give the genotype of the first grand daughter.

Haemophilia is a sex-linked recessive disorder in humans. The pedigree chart given below shows the inheritance pattern of haemophilia in a family. Study the inheritance pattern and answer the questions that follow:

(a) Give the possible genotypes of the members 4 and 5 in the above chart.
(b) A blood test shows that the member 14 is a carrier of haemophilia. The member 15 has recently married the member 14. What is the probability of their first child being haemophilic? Show it with the help of a Punnett square.

Read the following and answer any four questions from (i) to (v) given below:
A relevant portion of \(\beta\)-chain of haemoglobin of a normal human is as follows

The codon for the sixth amino acid is GAG. The sixth codon GAG mutates to GAA as a result of mutation X and into GUG as a result of mutation Y.
(i) Which of the following is incorrect statement?

(ii) Due to mutation Y the shape of RBCs under oxygen tension will be

(iii) GUG is code for

(iv) Which of the following genotype shows diseased phenotype due to mutation Y?

(v) Study the given pedigree chart for sickle-cell anaemia and select the most appropriate option for the genotypes.

Read the following and answer any four questions from (i) to (v) given below:
While studying inheritance of characters, a teacher gave the example of inheritance of attached earlobe and hypertrichosis of the ear to her students. A man with attached earlobes and extensive hair on pinna married a woman having free earlobes. The couple had four children, one son with attached earlobes and hairy pinna, one son with a free earlobes and hairy pinna and two daughters with attached earlobes. One of the daughters married a man with free earlobes and sparse hair on pinna. Teacher said if this couple would have sons there would be equal chances for both having free or attached earlobes and sparse hair on pinnae.
(i) Attached and free earlobe are respective example of

(ii) Hypertrichosis of the ear is

(iii) If a female with attached earlobe married a male homozygous for free earlobe sparse hair on pinna then what would be the chances of daughter to have attached earlobe?

(iv) If a man with attached earlobe and hairy pinna married a woman with attached earlobe then what would be the chances of son to have hairy pinna?

(v) A male with attached earlobe, sparse hair on pinna married a female with attached earlobe. Which of the following is correct regarding their progenies?