People who have darker skin have more melanin which is a black or dark brown pigment in the skin. When we are out in the sun our skin produces more melanin, which helps our skin be more resistant in the sun. This is why we tan.
Urethra as Nephrons form Kidney and Urethra isn't a part of Kidney.
Puberty or a more specific aspect of puberty
It can be found in tissues
Answer:
adaptations such as warning coloration, alarm calls and other signals, camouflage, mimicry of well-defended species, and defensive spines and chemicals.
Hope this helps with whatever you are working on :)
Explanation: