2 is the answer I THINK look at other ones first
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.
<span> Basically the male will have CC, the hen will have cc, and neither of them will have I. The key thing is that _all_ the chicks are coloured.
The male must have at least 1 C to be coloured, and cannot possess the dominant I. The hen has cc and/or an I to not be coloured.
That one chick is coloured would tell you little - only that the hen couldn't have 2 inhibitor alleles because otherwise the chick would have to have one and it doesn't.
However, for all of many chicks to be coloured, that means that the hen can't have any inhibitor alleles (otherwise around 50% would be white for that reason alone).
So to be colourless, the hen must be cc. However, if the male had only 1 colour allele (ie it was Cc) that would still mean that 50% of the chicks would be Cc (daddy's 'c' and one of mummy's 'c's).
Hope this helps please award brainly :)
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Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
