The portion of the electromagnetic spectrum that plays a role in the activation of vitamin d is visible light ultraviolet light infrared radiation microwaves

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.