There are 37.2 trillion cells in the human body
Answer:
Magnetite is black or brownish-black with a metallic luster, has a Mohs hardness of 5–6 and leaves a black streak.
ATP is the chemical substance that is used to power the cellular activities
Answer:
Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. ... Blood vessels nourish the cells in the hair bulb, and deliver hormones that modify hair growth and structure at different times of life, if that answers your question.
Explanation:
Answer:
B) There is an increase in the number of giraffes with long necks in areas of Africa where low-growing trees have died
Explanation:
The directional selection is one of the ways of the natural selection in which the natural selection selects or favours the most extreme trait of the species and the extreme trait show higher fitness than the normal or average trait.
In the given question, the case of Giraffe necks shows directional selection as the normal length of the neck is not favoured by the environment but the extreme trait that is long neck is favoured by the environment and the selection shifted to that level.
Thus, Option-B is the correct answer.