Thyroid hormone is classified as a steroid.
a. true
b. false

a. True

Explanation:

Hormones are signaling molecules that are produced by endocrine glands. The role of hormones is to control physiology or behavior. They can be classified into three categories: 

Peptide hormones – derived from a chain of amino acids

Amino acid or fatty acid hormones – derived from an amino acid or lipids respectively

Steroids – derived from cholesterol

Thyroid hormones are considered steroids. They are produced by the thyroid gland and are responsible for regulating metabolism.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.