phenylalanine

phenylalanine — noun

1. One of the building blocks of protein that the human body cannot produce on its

1.名詞C1
釋義

One of the building blocks of protein that the human body cannot produce on its own and must obtain from food. Found in meat, eggs, fish, dairy products, and some artificial sweeteners, it is converted by the liver into another amino acid called tyrosine, which the body uses to make important chemicals for the brain and nervous system.

例句

Babies born with phenylketonuria cannot break down phenylalanine, so they must follow a strict low-protein diet from birth.

passive: cannot break down + low-protein diet for PKU patients

Ayesha checked the label carefully because her son needed to limit his phenylalanine intake.

collocation: phenylalanine intake

用法筆記

Primarily used in medical and biochemical contexts. Frequently appears alongside phenylketonuria (PKU), a genetic disorder in which the body cannot metabolise this amino acid.

常見錯誤

Phenylalanine is a non-essential amino acid you do not need from food.
Phenylalanine is an essential amino acid that the body cannot make and must come from the diet.
💡'Essential' in biochemistry means the body cannot produce it; it must be eaten.