Without regular supplies of some hormones our capacity to behave would be seriously impaired; without others we would soon die.

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问题     Without regular supplies of some hormones our capacity to behave would be seriously impaired; without others we would soon die. Tiny amounts of some hormones can modify our moods and our action, our inclination to eat or drink, our aggressiveness or submissiveness, and our reproductive and parental behavior. And hormones do more than influence adult behavior; early in life they help to determine the development of bodily form and may even determine an individual’s behavioral capacities. Later in life the changing outputs of some endocrine glands and the body’s changing sensitivity to some hormones are essential aspects of the phenomena of aging.
    Communication within the body and the consequent integration of behavior were considered the exclusive province of the nervous system up to the beginning of the present century. The emergence of endocrinology as a separate discipline can probable be traced to the experiments of Bayliss and Starling on the hormone secretion. This substance is secreted from cells in the intestinal walls when food enters the stomach; it travels through the bloodstream and stimulates the pancreas to liberate pancreatic juice, which aids in digestion. By showing that special cells secrete chemical agents that are conveyed by the bloodstream and regulate distant target organs or tissues, Bayliss and Starling demonstrated that chemical integration can occur without participation of the nervous system.
    The term "hormone" was first used with reference to secretion. Starling derived the term from the Greek hormone, meaning "to excited or set in motion." The term "endocrine" was introduced shortly thereafter, "Endocrine" is used to refer to glands that secrete products into the bloodstream. The term "endocrine" contrasts with "exocrine" which is applied to glands that secrete their products through ducts to the site of action. Examples of exocrine glands are the tear glands, the sweat glands, and the pancreas, which secretes pancreatic juice through a duct into intestine. Exocrine glands are also called duct glands, while endocrine glands are called ductless.
The passage supports which of the following conclusions?

选项 A、The human body requires large amounts of most hormones.
B、Synthetic hormones can replace a person’s natural supply of hormones if necessary.
C、The quantity of hormones produced and their effects on the body are related to a person s age.
D、The short child of all parent very likely had a hormone deficiency early in life.

答案C

解析 题目询问文章支持下列哪个结论。定位于首段末句“到了中老年,身体内分泌的变化及身体对激素的反映变化是体现衰老现象的必要特征”。
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