Skin is the first line of defense mechanism of our immune system. It acts as a barrier for pathogenic and opportunistic microorganisms. However, skin itself has a microbiota that does not allow other microorganisms to invade or colonize. Any wound, cut or change in the pH of skin due to environmental conditions or any disease might lead to the entry of the opportunistic microorganisms inside the skin. This leads to several skin disorders such as dermatitis, eczema, cellulitis, warts, etc. Thus, it is extremely important to keep the skin hydrated and healthy to avoid any kind of microbial invasion.
As the earth has active tectonics we know that rocks are recycled and the oldest rocks may therefore just be the oldest rocks that have not been recycled yet. We know the true age of the earth by looking at radioactive isotopes of things like spacedust and meteors that formed at the same time as the earth as they have not been affected by the tectonic process of recycling here on Earth.
Involuntary action in body
Answer:
Label A is the amino group
Label B is the R group
Label C is the carboxyl group
Explanation:
