Human Health and Disease — BIOLOGY STD 12 Science — Question

What essential features must be present in a cloning vehicle/ cloning vector?

Write the steps you would suggest to be undertaken to obtain a foreign-gene-product.

A non–haemophilic couple was informed by their doctor that there is possibility of a haemophilic child be born to them. Explain the basis on which the doctor conveyed this information. Give the genotypes and the phenotypes of all the possible children who could be born to them.

1. A tRNA is charged with the amino acid methionine.

1. Name the process involved in the attachment.
2. Point out the mRNA codon and anticodon on RNA for this amino acid.

2. What is heterochromatin?

How do biofertilisers enrich the fertility of the soil?

The broadly utilitarian argument for the services provided by biodiversity. Describe.

A forest hardly has any carnivores. Census of herbivorous mammals was taken and plotted as a graph shown below:

Identify the curve that will explain the population growth of herbivores. Give reasons for your answer.

Identify 'a', 'b', 'c', 'd', 'e' and 'f' in the table given below:

No.	Syndrome	Cause	Characteristics of affected individual	Sex Male/Female/Both
1	Down’s	Trisomy of 21	‘a’ (i) (ii)	'b'
2	‘c’	XXY	Overall masculine development	‘d’
3	Turner’s	45 with OX	‘e’ (i) (ii)	‘f’

Draw a labelled diagram of a section through ovary.

Study the mRNA Segment given above which is complete to be translated into a polypeptide chain.

1. Write the codons ‘a’ and ‘b.'
2. What do they code for?
3. How is peptide bond formed between two amino acids in the ribosome?