proteins

Cultural  

1. Complex organic molecules (see also organic molecule) made up of amino acids. Proteins are basic components of all living cells and are therefore among the principal substances that make up the body. In addition to being necessary for the growth and repair of the body's tissues, proteins provide energy and act as enzymes that control chemical reactions in the cell.

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Foods that contain a high percentage of protein include meat, fish, poultry, milk products, beans, and nuts.

Example Sentences

It tells the cell both how to construct each of the complex proteins it needs to function and how to create new cells.

From The Wall Street Journal • Apr. 16, 2026

The team then narrowed their focus to proteins that are secreted outside cells, a key feature of hormones, and that contain multiple potential cleavage points.

From Science Daily • Apr. 12, 2026

In contrast, most laboratory studies remove the membrane-anchoring portion to make the proteins easier to handle.

From Science Daily • Apr. 12, 2026

To narrow the search, the team focused on an enzyme called prohormone convertase 1/3, which cuts proteins at specific locations and has been linked to obesity.

From Science Daily • Apr. 12, 2026

The most important proteins are enzymes, molecules that control the cell’s chemical reactions.

From "Cosmos" by Carl Sagan