The Hayflick Limit refers to which of the following processes?
A) HeLa cells continue to divide and grow.
B) Normal human cells grown in tissue culture go through a limited number of cell divisions.
C) Aging is regulated by glandular cells, perhaps of the hypothalamus, thymus, or pituitary gland.
D) Waste products and other harmful substances build up in the cells.
E) None of these.

Question

Quizplus · Accepted Answer

The Hayflick Limit refers to the observation made by Leonard Hayflick that normal human cells grown in tissue culture will only divide a finite number of times before entering a state of senescence, or irreversible growth arrest. This limit is thought to be due to the shortening of telomeres, the protective caps on the ends of chromosomes, with each cell division. Choice A is incorrect because HeLa cells are derived from a cancerous cervical tumor and have an unlimited potential for growth and division. Choice C is misleading because although glandular cells may play a role in aging, the Hayflick Limit specifically refers to cell division. Choice D is not directly related to the Hayflick Limit.

The Hayflick Limit Refers to Which of the Following Processes