2023年托福阅读理解冲刺题2023.docx
《2023年托福阅读理解冲刺题2023.docx》由会员分享,可在线阅读,更多相关《2023年托福阅读理解冲刺题2023.docx(12页珍藏版)》请在淘文阁 - 分享文档赚钱的网站上搜索。
1、2023年托福阅读理解冲刺题2023 托福阅读理解冲刺题2023 托福阅读理解是许多考生的心中之痛,如今yjbys考试网我为了关心考生顺利通过托福考试,特地推出以下托福阅读理解冲刺题一文。 Hormones in the Body Up to the beginning of the twentieth century, the nervous system was thought to control all communication within the body and the resulting integration of behavior. Scientists had dete
2、rmined that nerves ran, essentially, on electrical impulses. These impulses were thought to be the engine for thought, emotion, movement, and internal processes such as digestion. However, experiments by William Bayliss and Ernest Starling on the chemical secretin, which is produced in the small int
3、estine when food enters the stomach, eventually challenged that view. From the small intestine, secretin travels through the bloodstream to the pancreas. There, it stimulates the release of digestive chemicals. In this fashion, the intestinal cells that produce secretin ultimately regulate the produ
4、ction of different chemicals in a different organ, the pancreas. Such a coordination of processes had been thought to require control by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone. This discovery spurred Starling to coin the term hormone to refer to s
5、ecretin, taking it from the Greek word hormon, meaning ;to excite; or ;to set in motion.; A hormone is a chemical produced by one tissue to make things happen elsewhere. As more hormones were discovered, they were categorized, primarily according to the process by which they operated on the body. So
6、me glands which make up the endocrine system secrete hormones directly into the bloodstream. Such glands include the thyroid and the pituitary. The exocrine system consists of organs and glands that produce substances that are used outside the bloodstream, primarily for digestion. The pancreas is on
7、e such organ, although it secretes some chemicals into the blood and thus is also part of the endocrine system. Much has been learned about hormones since their discovery. Some play such key roles in regulating bodily processes or behavior that their absence would cause immediate death. The most abu
8、ndant hormones have effects that are less obviously urgent but can be more far-reaching and difficult to track: They modify moods and affect human behavior, even some behavior we normally think of as voluntary. Hormonal systems are very intricate. Even minute amounts of the right chemicals can suppr
9、ess appetite, calm aggression, and change the attitude of a parent toward a child. Certain hormones accelerate the development of the body, regulating growth and form; others may even define an inpidual’s personality characteristics. The quantities and proportions of hormones produced change w
10、ith age, so scientists have given a great deal of study to shifts in the endocrine system over time in the hopes of alleviating ailments associated with aging. In fact, some hormone therapies are already very common. A combination of estrogen and progesterone has been prescribed for decades to women
11、 who want to reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural levels of those hormones as they enter middle age. Known as hormone replacement therapy HRT, the treatment was also believed to prevent weakening of the bones. At least one study has li
12、nked HRT with a heightened risk of heart disease and certain types of cancer. HRT may also increase the likelihood that blood clots—dangerous because they could travel through the bloodstream and block major blood vessels—will form. Some proponents of HRT have tempered their enthusiasm i
13、n the face of this new evidence, recommending it only to patients whose symptoms interfere with their abilities to live normal lives. Human growth hormone may also be given to patients who are secreting abnormally low amounts on their own. Because of the complicated effects growth hormone has on the
14、 body, such treatments are generally restricted to children who would be pathologically small in stature without it. Growth hormone affects not just physical size but also the digestion of food and the aging process. Researchers and family physicians tend to agree that it is foolhardy to dispense it
15、 in cases in which the risks are not clearly outweighed by the benefits. 27. The word engine in the passage is closest in meaning to A desire B origin C science D chemical 28. The word it in the passage refers to A secretin B small intestine C bloodstream D pancreas 29. The word spurred in the passa
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 2023 托福 阅读 理解 冲刺
限制150内