Which of the following findings are considered part of normal aging? Select all that apply.

Ans: B, C
Feedback:
There is a decrease in the size of the thymus gland, which is thought to affect T-cell function. A suggested biologic clock in T cells that determines the number of times it divides may regulate cell number with age. Some researchers have reported a decrease in the absolute number of lymphocytes, and others have found little, if any, change. The most common finding is a slight decrease in the proportion of T cells to other lymphocytes and a decrease in CD4+ and CD8+ T cells. Evidence indicates that aged T cells have a decreased rate of synthesis of the cytokines that drive the proliferation of lymphocytes and a diminished expression of the receptors that interact with those cytokines. For example, it has been shown that IL-2, IL-4, and IL-12 levels decrease with aging. Although B-cell function is compromised with age, the range of antigens that can be recognized is not diminished.

Beauty