Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

1. Name the causative agent of amoebiasis and mention its symptoms.
2. Write how it spreads.

OR
A patient is down with Amoebiasis. List the symptoms that confirm this infection. Name the causative pathogen.

1. Why must a cell be made 'competent’ in biotechnology experiments? How does calcium ion help in doing so?
2. State the role of ‘biolistic gun’ in biotechnology experiments.

Explain the following with reference to drug/alcohol abuse:

1. Addiction.
2. Dependence.
3. Withdrawal symptoms

It has been recorded that the temperature of the earth’s atmosphere has increased by 0.6°C.

1. What has caused this increase?
2. Explain its consequences.

According to Darwinian theory, the rate of appearance of new forms is linked to their life cycles. Explain.

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 with a dwarf plant bearing white flowers, the different phenotypic groups were obtained in the progeny in numbers mentioned against them:
Tall, Red = 138
Tall, White = 132
Dwarf, Red = 136
Dwarf, White = 128
Mention the genotypes of the two parents and of the four offspring types.

Throughout sexual reproduction the chromosome number is maintained same. How is this done?

Recombinant DNA-technology is of great importance in the field of medicine. With the help of a flow chart, show how this technology has been used in preparing genetically engineered human insulins.

Write the three critical research areas of biotechnology.

The term ‘desirable trait’ can mean different things for different plants. Justify the statement with suitable examples.