Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Strands of hair originate in an epidermal penetration of the dermis called the hair follicle. The hair shaft is the part of the hair not anchored to the follicle, and much of this is exposed at the skin’s surface. The rest of the hair, which is anchored in the follicle, lies below the surface of the skin and is referred to as the hair root. The hair root ends deep in the dermis at the hair bulb, and includes a layer of mitotically active basal cells called the hair matrix. The hair bulb surrounds the hair papilla, which is made of connective tissue and contains blood capillaries and nerve endings from the dermis.
One's material and one's apparatus?
Answer:
To produce food is the correct answer.
I'd say that the mechanism which might keep Rana aurora and Rana boylii from mating is B. temporal isolation, since their breeding seasons do not occur at the same time.
It is not anatomical isolation, since they are both frogs. It is not geographic isolation, since they meet in California. It is not behavioral isolation since they both have breeding seasons.
