Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Biology

Sometimes cattle or even human beings give birth to their young ones that are having extremely different sets of organs like limbs/position of eye(s) etc. Comment.

The image below shows the result of plating bacteria in a chromogenic medium after incorporating the gene of interest in the plasmid. Some plates had blue colonies; some plates had white colonies. A single bacterium extracted from Plate I, II, and III is shown below:

On the basis of your observations:

1. Identify the plate(s) which is/are white. Give a reason.
2. Identify the plate(s) which is/are blue. Give a reason.

What do 'Y' and 'B' stand for in 'YAC' and 'BAC' used in Human Genome Project (HGP).

Mention their role in the project.

Why is the Human Genome project called a mega project?

Briefly describe the following:

Bioinformatics

Write the percentage of the total human genome that codes for proteins and the percentage of discovered genes whose functions are known as observed during HGP.

Expand 'SNPs' identified by scientists in HGP

Write any six salient features of the human genome as drawn from the human genome project.

Answer the following question.
Write the basis on which Alfred Sturtevant explained gene mapping.

Answer the following question.
List the two methodologies which were involved in the human genome project. Mention how they were used.

The human chromosome with the highest and least number of genes in them are respectively ______.

Which was the last human chromosome to be completely sequenced?

Diploid chromosome number in humans is ______.

Both husband and wife have normal vision though their fathers were colourblind. The probability of their daughter becoming colourblind is ______.

Haemophilia is more common in males because it is a ____________.

A colourblind girl is rare because she will be born only when ______.

A colourblind mother and normal father would have ______.

Of a normal couple, half the sons are haemophilic while half the daughters are carriers. The gene is located on ______.

Of both normal parents, the chance of a male child becoming colourblind are ______.

Genes located on Y-chromosome are ______.