13 - Chambered heart occurs in

HIV is a virus that damages the immune system. HIV is a lifelong condition, and without treatment, a person with HIV can develop AIDS.

Haemophilia is an inherited bleeding disorder where the blood doesn't clot properly. It is caused when blood does not have enough clotting factor.

The main treatment for hemophilia is called replacement therapy. Concentrates of clotting factor VIII (for hemophilia A) or clotting factor IX (for hemophilia B) are slowly dripped or injected into a vein. These infusions help replace the clotting factor that's missing or low.

Appetite is the desire to eat food, sometimes due to hunger. Appetite is triggered by environmental cues such as the smell or taste of food. Appealing foods can stimulate appetite even when hunger is absent.

According to psychologist Erik Erikson, Adolescence is the period of life between childhood and adulthood. They go through the psychosocial crisis of identity versus role confusion, which involves exploring who they are as individuals. During this stage, adolescents explore their independence and develop a sense of self i.e independent identity, ego nature.