These are dendritic cells; these are professional antigen-presenting cells located in the skin, mucosa and lymphoid tissues and promote immunity
It starts in the mouth and makes it way through the throat, drops to the stomach and finishes in the small intestines.
Living indicators are species that are sensitive to changes in the environment. For example air pollution can be monitored by looking at lichen, which are sensitive to sulphur dioxide in the air. The number of lichen at a particular location indicates how clear the air is. Similarly, mayfly larvae are good indicators for water pollution because they're sensitive to the concentration of dissolved oxygen in water.
Non-living indicators are things like satellites which can measure the temperature of the sea surface, weather stations that measure atmospheric temperature, rain gauges to measure rainfall, and dissolved oxygen meters to measure concentration of dissolved oxygen in water.
Answer:
Through Mutation
Explanation:
Since our cells are able to produce exact copies of themselves. Thus, until unless some mutation has occurred and affected the ability of the cells to produce exactly similar duplicates copies of the parent cell, there is no way that an individual gets aged.
Since, mutation affects the mitochondrial DNA it is pretty sure that a mutated cell has affected the longevity of a normal cell and then that mutated cell has produced million other mutated aged cell by replicating itself
