Microsporum and Trichophyton are the two fungus that are responsible for ringworms. Symptoms include appearance of dry, scaly lesions on various parts of the body such as skin, nails and scalp with intense itching. The fungus are generally found in skin folds such as those in the groin or between the toes because the heat and moisture help in these organs help these fungi to grow and thrive.
(a) Mention the cause and the body system affected by ADA deficiency in humans.
(b) Name the vector used for transferring ADA-DNA into the recipient cells in humans. Name the recipient cells.(a) Name the group of viruses responsible for causing AIDS in humans. Why are these viruses so named?
(b) List any two ways of transmission of HIV infection in humans, other than sexual contact.
(a) Draw a neat labelled diagram of a nucleosome.
(b) Mention what enables histones to acquire a positive charge.