P450scc or cholesterol side chain cleavage enzyme is an enzyme that converts cholesterol into pregnenolone (the precursor for steroids). The kinds of steroid hormones are mineralocorticoids (i.e. aldosterone) glucocorticoids (i.e. cortisol), and sex steroids (i.e. testosterone, estrogen). In the event where P450scc is blocked, then there will be no production of mineralocorticoids, glucocorticoids, and sex steroids. There will be no production of aldosterone, cortisol, estradiol, testosterone, and progesterone. This disease is called Lipoid Congenital Adrenal Hyperplasia.
Answer:
The nitrogen cycle could not exist without first nitrogen. The cycle is about this specific element which goes to show that if this element is not present then, there will not be any nitrogen cycle. Also, an important factor for the cycle is the presence of the bacteria and other microorganism which are needed for the fixation.
D. This is because artificial selection is basically the human breeding of plants or animals, and we do so in a way to bring forth the best traits to solve a problem or create a better product.
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