The approximately 10 million cells in human body can divide only a certain number of times before they began to age and stop reproducing, a phenomenon known as the

This phenomenon is known as Hayflick limit.

Explanation:

Hayflick's limit was discovered by Leonard Hayflick in 1965. Hayflick noted that every time a cell replicates, it eventually has its telomere diminished. With each new cell having smaller telomeres, they begin to age, presenting more problems, until the critical limit is reached and the cell stops reproducing and can no longer live.

Telomeres are buffers at the ends of the chromatids that prevent the breakdown of genes.

The discovery of this decrease, which causes aging in cells, is linked to natural human aging. In addition, smaller telomeres make room for many problems due to decreased immune capacity in cells, which may pave the way for cancer and other diseases that attack our cells.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.

compost can be added to topsoil as a:

pesticide