Question Bank [2022] — BIOLOGY STD 12 Science — Question

How is an autoimmune disease caused? Mention one such disease in humans.

Explain what happens in frameshift mutation. Name one disease caused by the disorder.

Why is Rhizobium categorised as a ‘symbiotic bacterium’? How does it act as a biofertiliser?

Explain the process of RNA interference.

Classify the following diseases under the headings 'transmissible and 'non-transmissible'. Lung cancer, whooping cough, rickets, arthritis, appendicitis, food poisoning, tuberculosis, measles, diabetes, anaemia, syphilis, influenza, AIDS, coronary heart disease and haemophilia.

Name the two different categories of microbes naturally occurring in sewage water. Explain their role in cleaning sewage water into usable water.

Write the function of each of the following:
Luteinising hormone in human males.

Draw a labelled diagram – Working of lac operon.

In peas, tallness is dominant over dwarfness, and red colour of flowers is dominant over the white colour. When a tall plant bearing red flowers was pollinated by a dwarf plant bearing white flowers, the different phenotypic groups were obtained in the progeny.
Tall, Red = 138
Tall, White = 132
Dwarf, Red = 136
Dwarf, White= 128
Mention the genotypes of the two parents and of the types of four off springs. in numbers mentioned against them.

Write a note on hygroscopic water and combined water.