List of top Questions asked in CBSE CLASS XII

With a suitable example, explain briefly, why the number of predicted genes do not correlate with the genome size and the number of chromosomes in an organism.

Describe briefly, the charge relay system that operates in chymotrypsin enzyme.

What is the principle of mass spectrometry? Write its important application.

Two statements are given – one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the codes given below:
Assertion (A): One of the first attempts to study the molecular basis of sickle cell anaemia was to compare the electrophoretic mobility of normal haemoglobin (Hb) and sickle cell haemoglobin (scHb).
Reason (R): Sickle cell haemoglobin (scHb) moved faster than normal haemoglobin (Hb) in electrophoresis.

Two statements are given – one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the codes given below:
Assertion (A): Proteins have diverse functions.
Reason (R): All proteins are enzymes.

Two statements are given – one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the codes given below:
Assertion (A): Contact inhibition is absent in cancer cells.
Reason (R): Normal cells stop growing when they reach the walls of the container.

Two statements are given – one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the codes given below:
Assertion (A): CO₂ incubators prevent the desiccation of the animal cell culture medium.
Reason (R): A pan of water is kept at all times in a CO₂ incubator chamber to maintain high relative humidity.

Herceptin is a monoclonal antibody approved for:

Identification of disease specific proteins can be done by using the approach of:

_______ can be categorized as a food source of nutraceutical proteins.

Gene prediction for bacterial genomes can be done by using the computer program _______.

The technique to isolate and grow human embryonic stem cells in culture was developed by:

Absence of the enzyme adenosine deaminase in humans causes:

A biotechnologist wants to obtain a gene sequence in single stranded form. Which bacteriophage based vector should he choose to obtain the desired result?

One of the carbon sources used in microbial cell culture is:

Single base difference in ApoE gene is associated with:

At the end of one cycle of PCR, two DNA molecules will become ________ .

Protein Efficiency Ratio (PER) is used as a measure of growth expressed in terms of:

The DNA ligase enzyme that is frequently used to ligate different DNA fragments in order to generate rDNA molecules is isolated from:

1,000 units of raw material were introduced in a process at a cost of ₹ 4,000. The normal wastage allowed is 10%, each unit of waste realises ₹ 2.50. The actual production was 850 units (with abnormal wastage of 50 units). The expenses being as follows:
Direct wages {2cm} ₹ 6,500
Indirect expenses {1.6cm} ₹ 3,250
Prepare the process account to show the effect of wastage.