Final answer:
Cholesterol is the most abundant steroid in the human body and is found in animal products. It is an essential component of cell membranes and serves as a precursor for hormones, bile acids, and vitamin D.
Step-by-step explanation:
Cholesterol does not occur in plants, but it is the most abundant steroid in the human body. It is found in animal products and is synthesized by the liver in humans and animals. Cholesterol is an essential component of cell membranes, a precursor for hormones, bile acids, and vitamin D.