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.
Answer:
<em>D. All of the above </em>
Explanation:
This is an effective strategy because different phases do not compete for food.
For example for the case of Jelly fish, After a brief period floating about in surface waters like planktons, the larvae then settles to the sea floor, attaching themselves to one end. They then develop to polyps and begin to feed and grow. In spring the polyps bud iff immature jellyfish known as ephyra larvae which then grow to mature jellyfish.
<span>Option D correctly describes seafloor spreading. Seafloor spreading is a process which typically occur at middle ocean ridges where new oceanic crusts are formed as a result of volcanic activity. These oceanic crusts then gradually move away from the ridge.</span>
