Oh this one is so cool!
It basically all boils down to Vitamin D! We need this essential vitamin to help our body build hormones and regulate calcium. Our bodies make Vitamin D when we are exposed to the UV rays found in sunlight. But as we all know, too much sunlight isn’t good because these UV rays can harm us. Melanin (the chemical that our bodies produce to darken skin tone and hair color) provides protection from UV rays by absorbing them. However, this means that the more melanin that is produced by someone’s body results in less absorption of UV rays and a decrease in Vitamin D production. But for someone living around the equator or in the tropics that doesn’t matter because there’s lots of sun all the time. So for humans living in these areas where there’s lots of sunlight year round, it’s beneficial to have darker skin to protect from the harm of UV rays. People living in these areas still get plenty of Vitamin D though because of that year round sunshine.
Now what about those who’s skin has less melanin, such as those found in the higher latitudes? Well with less sunlight year round, their bodies had to adapt to be able to get enough Vitamin D. So less melanin is produced by the body in order to absorb the lesser amounts of UV rays to make Vitamin D. Lighter skin is, therefore, more beneficial the farther away you go from the tropics.
So essentially:
Pro of Darker Skin tones
-Protection from harmful UV rays
Con of Darker Skin tones
-Less absorption of UV rays and less production of Vitamin D
Pro of Lighter Skin tones
-Greater absorption of UV rays and more Vitamin D production
Con of Lighter Skin tones
-Less protection from harmful UV rays (resulting in sunburns and, in extreme cases, skin cancer)
This is of course the biology answer. The social impacts of different skin tones is a whole different story that you can ask in the history section.
Answer:
b if a bananas is grow in direct sunlight it will contain more potassium
Answer:
The two types of cells that never go through cell division once fully formed are nerve cells and muscle cells.
Explanation:
The nerve cells and the muscle cells not undergo cell division after formation, because they can never re grow or cannot be repaired once they are mature. We should take good care of it once they are matured. They just under division from being baby to teenagers after that they stop undergoing cell division. This is true for both elephants as well as human beings. This thing is also applicable in case of bones.
The question is incomplete, I included an attachment that completes the question as well as show the options to be chosen from.
Answer: YES, SUPPORTED
Explanation: When we talk of Osmoconformers, we are talking of the organisms that live in the marine habitat.
These Osmoconformers have the tendency of maintaining their internal fluid isotonic that is isotonic to their external environment in church they live. They have an osmotic pressure that is equal to the osmotic pressure of their surrounding environment.
In the table provided in the attachment section,it clearly stated as we can see the increase in osmolarity of water,the haemolymph osmolarity increase in order to maintain isotonic realtion so that,there will be no much exosmosis (osmosis).