_____, which is abundant in almost all proteins, is converted to niacin in the body.
1.Arginine
2.Tryptophan
3.Alanine
4.Tyrosine
5.Lysine
Question 2
The importance of the lungs in the circulatory system is that they are responsible for:
a. adding oxygen to the blood.
b. removing glucose from the blood.
c. adding nutrients to the blood.
d. removing extra water from the blood.
e. removing carbon monoxide from the blood.