Answer:
Lightly pigmented people tend to be at higher risk of vitamin D deficiency
Explanation:
BACKGROUND KNOWLEDGE:
Human skin is the largest organ of the body which makes boundary line between environment and internal conditions. Human skin cell produces pigment called melanin when ever it is subjected to Sun. More the melanin pigment produced more will be the skin darkens. Ultraviolet (UV) radiations also come from Sun and responsible for more pigmentation.
ANSWER EXPLANATION:
According to the question darkly pigmentation only occurs when their is high level of UV radiations. High level of UV radiations are also responsible for Vitamin D production.
People with lightly pigmented means that there environment has low level of UV radiations which are the requirement of Vitamin D production. Hence due to low UV radiations peoples with light pigmentation's are also be at higher risk of vitamin D deficiency
Phase 1: Starts with the separation between populations. Separated populations become adapted to local conditions and become genetically differentiated over time.
Phase 2: Genetic isolation is completed, reproductive isolation develops mostly in the forms of prezygotic RIMs.
I would say that this would be 2. Breaks down existing landforms to create new ones
answer is antibodies.
B cells are a type of lymphocytes and it is responsible for the immune system. B cells help to protect body by producing specific antibodies to fight against each antigen which are strangers to the body specially for viral infections.