why the skin cells of an adult must divide?

is it because they are in the direct contact with the things from the outside world. they have to replace the new skin cell from the dead cell

The skin cells of an adult must divide because the skin is constantly exposed to the outside world and undergoes regular wear and tear. By dividing, the skin cells can efficiently replace old, damaged, or dead cells with new ones, ensuring the skin's health and integrity.

The process of skin cell division is called mitosis. It involves the division of one parent cell into two daughter cells that are genetically identical to each other and to the parent cell. This ensures that the newly formed cells can perform their functions effectively and maintain the barrier between the body and the external environment.

To understand why skin cells need to divide, it is important to know that the skin is composed of several layers, with the outermost layer being the epidermis. The epidermis is responsible for protecting the body from harmful substances, preventing excessive water loss, regulating body temperature, and providing a waterproof barrier.

As the outermost layer, the cells of the epidermis are constantly exposed to friction, ultraviolet (UV) radiation, pollutants, and microorganisms. These factors can lead to cellular damage, cell death, and the need for replacement. Additionally, the epidermis also undergoes natural shedding, where dead skin cells are sloughed off and replaced by new cells.

When skin cells divide, they replenish the supply of cells in the epidermis, ensuring that there are enough healthy cells to replace those that are lost or damaged. This replenishment process helps protect the body from infections, aids in wound healing, and maintains the overall health and functionality of the skin.

In summary, the division of skin cells in adults is necessary to replace old, damaged, or dead cells caused by external factors and natural shedding. This process ensures the proper functioning and integrity of the skin as a protective barrier for the body.