Describe the role of the following in human beings:
(i) Seminal vesicles
(ii) Prostate gland
Seminal vesicles: Secretions of seminal vesicles have several proteins and enzymes and so they provide nutrition to the developing sperms.
Prostate gland: It secretes a slightly alkaline fluid which lubricates sperms and neutralises acidity of vaginal tract.
Modes of spread of AIDS:
- By contaminated blood transfusion from a infected person to healthy one.
- From mother to child by placenta.
- By unprotected sexual contact with infected person of HIV.
- By using infected needles for injection to a person.