Question

1. which of the following lists of amino acids contain all essential amino acids?

valine, threonine, lysine, methionine
glutamine, proline, tryptophan, histidine
tyrosine, arginine, phenylalanine, cysteine
phenylalanine, methionine, glycine, serine

1. alcohol is an addictive substance.

true
false

1. this lipoprotein is often called the \bad\ cholesterol.

intermediate - density lipoprotein
high - density lipoprotein
low - density lipoprotein
very - low - density lipoprotein

Explanation:

1. Essential amino acids are those that the body cannot synthesize on its own and must be obtained from diet. Valine, threonine, lysine, and methionine are among the essential amino - acids. Glutamine, proline, glycine, serine are non - essential. Tyrosine and cysteine are conditionally essential.
2. Alcohol is known to be an addictive substance as it affects the brain's reward system and can lead to physical and psychological dependence.
3. Low - density lipoprotein (LDL) is often called the "bad" cholesterol because it can deposit cholesterol in the arteries, increasing the risk of cardiovascular diseases. High - density lipoprotein (HDL) is considered "good" cholesterol. Intermediate - density lipoprotein and very - low - density lipoprotein have different functions and roles in lipid metabolism.

Answer:

1. Valine, threonine, lysine, methionine
2. True
3. Low - density lipoprotein