Answer:
The integumentary system.
Explanation: The integumentary system is the on that is responsible for regulation and synthesis of the vitamin D. Remember this, Vitamin D for the skin is found when the sunlight has absorbed on the skin. Hope this helps!
Amino acids consumed in excess of the amounts needed for the synthesis of nitrogenous tissue constituents are not stored but are degraded; the nitrogen is excreted as urea, and the keto acids left after removal of the amino groups are either utilized directly as sources of energy or are converted to carbohydrate or fat
Hope that helped <3
<u>This question is off-topic, but I'm answering it assuming you meant to categorize as maths.</u>
Answer:
or 
Explanation:
<u>Factoring</u>
It consists of converting an algebraic expression, usually as a polynomial into two or more factored terms.
We must find the greatest possible common factor and use it to modify the original expression.
The given expression is

It's evident that both terms have a numeric common factor of -9. Let's factor by -9. We must divide each term by -9 to get:

We can even factor further by writing
