(a) List the three states the annuals and biennial angiosperms have to pass through during their life cycle.
(b) List and describe any two vegetative propagules in flowering plants.
(a) The three states through which the annuals and biennial angiosperms pass during their life cycle are:
(i) Vegetative or Juvenile phase
(ii) Reproductive phase
(iii) Senescent phase
(b) Vegetative propagules are the parts/units of a plant which can be used for vegetative propagation, e.g. roots, stems, leaves, etc. Root propagules include the production of a new plant via roots, e.g. fleshy roots in case of sweet potato, tapioca and Dahlia. Vegetative propagation through leaves, many plant leaves have adventitious buds which help in the development of a new plant, e.g. Begonia, Bryophyllum, etc.
During a medical investigation, an infant was found to possess an extra chromosome 21. Decribe the symptoms the child is likely to develop later in the life.
A number of passengers were severely burnt beyond recognition during a train accident. Name and describe a modern technique that can help hand over the dead to their relatives.
(a) What precaution(s) would you recommend to a patient requiring repeated blood transfusion?
(b) If the advise is not followed by the patient there is an apprehension that the patient might contract a disease that would destroy the immune system of his/her body. Explain with the help of schematic diagram only how the immune system would get affected and destroyed.
(a) What is inbreeding depression?
(b) Explain the importance of ‘selection’ during inbreeding in cattle.
Explain the role(s) of the following in biotechnology.
(a) Restriction endonuclease
(c) Selectable markers in pBR322