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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 moods and actions, 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 probably 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 secret chemical agents that are conveyed by the bloodstream and regulate distant target organs or tissues. Bayliss and starling demonstrated that chemical integration could 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 excite or set in motion. The term “endocrine” was introduced shortly thereafter “Endocrine” is used to refer to glands that secret products into the bloodstream. The term “endocrine” contrasts with “exocrine”, which is applied to glands that secret their products though ducts to the site of action. Examples of exocrine glands are the tear glands, the sweat glands, and the pancreas, which secrets pancreatic juice through a duct into the intestine. Exocrine glands are also called duct glands, while endocrine glands are called ductless.
1.What is the author’s main purpose in the passage?
A.To explain the specific functions of various hormones.
B.To provide general information about hormones.
C.To explain how the term “hormone” evolved.
D.To report on experiments in endocrinology.
2.The passage supports which of the following conclusions?
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 tall parents very likely had a hormone deficiency early
in life.
3.It can be inferred from the passage that before the Bayliss and Starling
experiments, most people believed that chemical integration occurred
only___.
A.during sleep.
B.in the endocrine glands.
C.under control of the nervous system.
D.during strenuous exercise.
4.The word “liberate” could best be replaced by which of the following?
A.Emancipate B.Discharge C.Surrender D.Save
5.According to the passage another term for exocrine glands is___.
A.duct glands
B.endocrine glands
C.ductless glands
D.intestinal glands.
In the earliest stages of man's development he had nomore need of money than animals have.He was content with very simple forms of shelter,made his own rough tools and weapons and could provide food and clothing for himself and his family from natural materials around him.As he became more civilized,however,he began to want better shelter,more efficient tools and weapons,and more comfortable and more lasting clothing than could be provided by his own neighborhood or by the work of his own unskilled hands.For these things he had to turn to the skilled people such as smiths,leather workers or carpenters.It was then that the question of payment arose.
At first he got what he wanted by a simple process ofexchange.The smith who had not the time to look after land or cattle was glad to take meat or grain from the farmer inexchange for an axe or a plough.But as more and more goods which had no fixed exchange value came on the market,exchange became too complicated to be satisfactory.Another problem arose when those who made things wanted to get stocks of wood or leather,or iron,but had nothing to offer in exchange until their finished goods were ready. Thus the difficulties of exchange led by degrees to the invention of money.In some countries easily handled things like seeds or shells were given a certain value and the farmer,instead of paying the smith for a new axe by giving him some meat or grain,gave him so many shells.If the smith had any shells left when he had bought his food,he could get stocks of the raw materials of his trade.In some countries quite large things such as cows or camels or even big flat stones were used for trade.Later,pieces of metal,bearing values according to the rarity of the metal and the size of the pieces,or coins were used.Money as we know it had arrived.
1.Exchange of goods became difficult because _________.
A man became more civilized
B smiths began to look after land or cattle in their spare time
C more and more goods which had no fixed exchange alues came to the
marker
D farmers hadn't enough grain or meat to provide for
skilled workers
2.Money was not used until _______.
A paper was invented
B people practiced a simple process of exchange
C nothing could be offered in exchangeD the exchange of one thing for another became too complicated
3.The best title for this passage is _____.
A What is money
B What are money's functions.
C The importance of money
D The beginning of money
