Identify'A' , 'B', 'C' and 'D' in the given table
Crop | Variety | Resistance to disease |
A | Himgiri | Leaf rust |
Cauliflower | Pusa Shubhra | B |
Brassica | Pusa Swarnim | C |
Cowpea | D | Bacterial blight |
Why is breast-feeding recommended during the initial period od an infant's growth? Give reasons.
Give an example of an autosomal recessive trait in humans. Explain its pattern of inheritance with the help of a cross.
Suggest and describe a technique to obtain multiple copies of a gene of interest in vitro.
During a school trip to 'Rohtang pass' one of your classmate suddenly developed 'Altitude sickness'. But, she recovered after sometime.
(a) Mention one symptom to diagnose the sickness.
(b) What causes the sickness?
(c) How could she recover by herself after sometime?
(a) The symptoms of altitude sickness are fatigue and nausea.
(b) Altitude sickness is caused as the body does not get enough oxygen because of the low atmospheric pressure.
(c) After some time the body usually gets acclimatised. The body compensates low oxygen availability by increasing red blood cell production, decreasing the binding affinity of haemoglobin and by increasing breathing rate.
How has RNAi technique helped to prevent the infestation of roots in tobacco plants by a nematode Meloidegyne incognita?
In in a food-chain, a trophic level represents a functional level, not a species. Explain.