Are a group of organic compounds including fats, phospholipids, and steroids.
proteins
carbohydrates
lipids
nucleic acids

Answer : The correct answer for the blank is -

Lipids.

Lipids can be described as one of the four major macromolecules that are essential for the survival of life forms. They are water soluble organic compound and are major constituent of cell membrane in biological systems.

There are three major categories of lipids, which include steroids, phospholipids, and triglycerides (obtained from food sources such as fats and oil).

Thus, Lipids is the right answer.

an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme

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