The correct answer is: D. Enzymes
Enzymes are biological catalysts, which means they speed up the rate of chemical reactions without being consumed by the reaction. They are essential for life, as they are responsible for catalyzing the vast majority of chemical reactions that take place in cells.
Hormones are chemical messengers that are produced by glands and transported in the blood to target cells, where they regulate physiological processes. Vitamins are essential nutrients that are required for normal growth and development. Steroids are a group of lipids that are produced by the body and have a variety of functions, including regulating metabolism, reproduction, and immune function.
Here are some additional details about each of the options:
- Hormones are chemical messengers that are produced by glands and transported in the blood to target cells, where they regulate physiological processes. Hormones are essential for life, as they control many important bodily functions, such as growth, development, metabolism, and reproduction.
- Vitamins are essential nutrients that are required for normal growth and development. Vitamins are not produced by the body, so they must be obtained from food. There are 13 essential vitamins, which are divided into two groups: fat-soluble vitamins (A, D, E, and K) and water-soluble vitamins (B vitamins and vitamin C).
- Steroids are a group of lipids that are produced by the body and have a variety of functions, including regulating metabolism, reproduction, and immune function. Steroids are derived from cholesterol, and they are found in all parts of the body. Some steroids are produced naturally by the body, while others are produced synthetically. Steroids can be used to treat a variety of medical conditions, such as asthma, arthritis, and cancer. However, they can also be abused, as they can produce a number of side effects, including addiction, heart problems, and liver damage.
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