医学英语新教程-习题参考答案Unit 4

Unit Four

Human Physiology

Section A

1—c 2—g 3—h 4—b 5—i

6—a 7—f 8—e 9—j 10—d

Section B

Passage 1

I. Reading Comprehension

1.What does physiology deal with?

Physiology is the study of processes and functions in living organisms. It is a broad field that encompasses many disciplines and has strong roots in physics, chemistry, and mathematics. The scope of physiology ranges from the activities or functions of individual molecules and cells to the interaction of our bodies with the external world. An important part of physiology is understanding how different parts of the body are controlled, how they interact, and how they adapt to changing conditions.

2.What are the common characteristics of different forms of cells?

Though cells differ widely in form and function, they all have certain common characteristics. First, they are bounded by a limiting membrane, the plasma membrane. Secondly, they have the ability to break down large molecules to smaller ones to liberate energy for their activities. Thirdly, at some point in their life history, they possess a nucleus which contains genetic information in the form of deoxyribonucleic acid.

3.Could you describe the functions of the right ventricle and the left ventricle?

Contractions of the right ventricle propel deoxygenated blood through the lungs where it absorbs oxygen from the air, while the left ventricle pumps oxygenated blood returning from the lungs to the rest of body to supply the tissues.

4.How do you understand the concept of balance in the human body?

The concept of balance is very important to human body. It can be applied to any of the body constituents including water and salt. Intake must match requirements and any excess must be excreted to maintain balance. If balance can’t be maintained well, sickness even death may happen.

5.What are two coordinating systems and how do they perform their functions?

Two coordinating systems are the nervous system and the endocrine system. The nervous system coordinates the movements of the limbs and body, stimulates the

muscles to contract, and senses muscle tension and limb position. The endocrine system helps adjust blood flow and the supply of various metabolic substrates to the working muscles. The endocrine system produces hormones which travel in the bloodstream to the cells upon which they exert a regulatory effect.

6—A 7—A 8—D 9—B 10—D

II. Vocabulary Study

Part A

1—platelets 2—physiological 3—Extracellular 4—nitrogen 5—Indigestible 6—urinary 7—lymphatic 8—glycogen 9—deoxygenated 10—oxidation

Part B

1—excrete 2—Evolution 3—stabilize 4—locomotion

5—notion 6—dysfunction 7—intricate 8—endowed

9—liberate 10—exquisitely

III. Translation

Part A

1.The success of physiology in explaining how organisms perform their daily tasks

is based on the notion that they are intricate and exquisite machines whose operation is governed by the laws of physics and chemistry.

生理学成功地解释了生物体如何进行日常活动，基于的观点是生物体好比是结构复杂而灵巧的机器，其运行机制受物理和化学规律的调控。

2.Although it is helpful to study how each organ performs its functions, it is

essential to recognize that the activity of the body as a whole is dependent on the intricate interactions between the various organ systems.

虽然研究各器官如何行使功能很有益处，但我们必须认识到机体作为一个整体所做的活动依赖于各器官系统间错综复杂的相互作用。

3.If there is an excess of potassium in the extracellular fluid, the cardiac muscle

cells become too excitable and may contract at inappropriate times rather than in

a coordinated manner.

如果细胞外液中钾离子过多，心肌细胞的兴奋性增强，可能出现不规律收缩。

4. A negative feedback loop requires a sensor of some kind that responds to the

variable in question but not to other physiological variables.

负反馈环是在机体出现紊乱时，通过感受器对出现的各种问题做出反应，而不是对其他生理变化做出反应。

5.Each functional structure contributes its share to the maintenance of homeostatic

conditions in the extracellular fluid, which is called the internal environment.