At the end of each chapter, the material is summarized in outline form. This outline summary is organized by major section headings with page references, followed by the key points in the section. Students may read the summary after studying the chapter to be sure that they haven't missed any points, and can use the chapter summaries to help review for examinations.
Summary introduction to Phyiiotogy 4
I. Physiology is the study of how cells, tissues, and organs function.
A. In the study of physiology, cause-and-effect sequences are emphasized.
B. Knowledge of physiological mechanisms is deduced from data obtained experimentally.
II. The science of physiology overlaps with chemistry and physics and shares knowledge with the related sciences of pathophysiology and comparative physiology.
A. Pathophysiology is concerned with the functions of diseased or injured body systems and is based on knowledge of how normal systems function, which is the focus of physiology.
B. Comparative physiology is concerned with the physiology of animals other than humans and shares much information with human physiology.
III. All of the information in this book has been gained by applications of the scientific method. This method has three essential characteristics.
A. It is assumed that the subject under study can ultimately be explained in terms we can understand.
B. Descriptions and explanations are honestly based on observations of the natural world and can be changed as warranted by new observations.
C. Humility is an important characteristic of the scientific method; the scientist must be willing to change his or her theories when warranted by the weight of the evidence.
Test Your Knowledge of Terms an
Match the following (1-4): 1. Glands are a. derived from b.
nervous tissue connective tissue muscular tissue epithelial tissue
Cells are joined closely together in Cells are separated by large extracellular spaces in
Blood vessels and nerves are usually located within
Most organs are composed of a. epithelial tissue.
b. muscle tissue.
Sweat is secreted by exocrine glands. This means that a. it is produced by epithelial cells.
is secreted duced outside the body.
Which of the statements about homeostasis a. The internal maintained absolutely b. Negative feedback mechanisms act to correct deviations from a normal range within the internal c. Homeostasis is maintained by switching effector actions on and off.
d. All of these are true.
In a negative feedback loop, the effector organ produces changes that are a. in the same direction as the change produced by the initial stimulus.
b. opposite in direction to the change produced by the initial stimulus.
c. unrelated to the initial stimulus.
A hormone called parathyroid hormone acts to help raise the blood calcium conaentration. According to the principles of negative feedback, an effective stimulus for parathyroid hormone secretion would be a. a fall in blood calcigm.
theefsfe ctoonrstihstastocfadnebneseacptairvaaltleld arrangem on fibers?
skeletal musclé tissue c. tendons d. dermis of the skin The act of breathing ra oxygen level, lowers the blood carbon dioxide concentration, and raises the blood pH. According to the principles of negative feedback, sensors that regulate breathing should respond to a. a rise in blood oxygen.
c. a rise in blood carbon dioxide the blood
Test Your Understanding of Concepts and Principles
1. Describe the structure of the various epithelial membranes and explain how their structures relate to their functions.'
2. Compare bone, blood, and the dermis of the skin in terms of their similarities. What are the major structural differences between these tissues?
3. Describe the role of antagonistic negative feedback processes in the maintenance of homeostasis.
4. Using insulin as an example, explain how the secretion of a hormone is controlled by the effects of that hormone's actions.
Test Your Ability to Analyze and ApplyYour Knowledge
1. What do you think would happen if most of your physiological regulatory mechanisms were to operate by positive feedback rather than by negative feedback? Would life even be possible?
Examine figure '.5 and determine when the compensatory physiological responses began to act, and how many minutes they required to restore the initial set point of blood glucose n. Comment on the ell of these.
Describe the steps in the development of pharmaceutical drugs and evaluate the role of animal research in this process. Why is Claude Bernard considered the father of modern physiology? Why is the concept he introduced so important in physiology and medicine?
importance of quantitative measurements in physiology. Why are interactions between the body-fluid compartments essential for sustaining life?
Check out the Links Library at www.mhhe.com/fox8 for links to sites containing resources related to the study of body function. These links are monitored to ensure current URLs.
d in the chapter 1 Study Guide found on the Oi
2. In a negative feedback loop, the effector acts to cause changes in the internal environment that compensate for the initial deviations that were detected by the sensor.
B. Positive feedback loops serve to amplify changes and may be part of the action of an overall negative feedback mechanism.
C. The nervous and endocrine systems provide extrinsic regulation of other body systems and act to maintain homeostasis.
D. The secretion of hormones is stimulated by specific chemicals and is inhibited by negative feedback mechanisms.
II. Effectors act antagonistically to defend the set point against deviations in any direction.
I. The body is composed of four primary tissues: muscle, nervous, epithelial, is secreted nervous tissue connective tissue muscular tissue epithelial tissue
There are three types of muscle tissue: skeletal, cardiac, and smooth muscle.
1. Skeletal and cardiac muscle are striated.
2. Smooth muscle is found in the walls of the internal organs.
Nervous tissue is composed of neurons and supporting cells.
1. Neurons are specialized for the generation and conduction of electrical impulses.
2. Supporting cells provide the neurons with anatomical and functional support.
Epithelial tissue includes membranes and glands.
1. Epithelial membranes cover and line the body surfaces, and their cells are tightly joined by junctional complexes.
2. Epithelial membranes may be simple or stratified and their cells may be squamous, cuboidal, or columnar.
3. Exocrine glands, which secrete into ducts, and endocrine glands, which lack ducts and secrete hormones into the blood, are derived from epithelial membranes.
D. Connective tissue is characterized by large intercellular spaces that contain extracellular material.
1. Connective tissue proper is categorized into subtypes, including loose, dense fibrous, adipose, and others.
2. Cartilage, bone, and blood are classified as connective tissues because their cells are widely spaced with abundant extracellular material between
Organi and Syitemi ¡7
I. Organs are units of structure and function that are composed of at least two, and usually all four, primary tissues.
A. The skin is a good example of an
1. The epidermis is a stratified squamous keratinized epithelium that protects underlying structures and produces vitamin D.
2. The dermis is an example of
3. Hair follicles, sweat glands, and sebaceous glands are exocrine glands located within the dermis.
4. Sensory and motor nerve fibers enter the spaces within the dermis to innervate sensory organs and smooth muscles.
5. The arrector pili muscles that attach to the hair follicles are composed of smooth muscle.
B. Organs that are located in different regions of the body and that perform related functions are grouped into systems. These include, among others, the circulatory system, digestive system, and endocrine system.
II. The fluids of the body are divided into two major compartments.
A. The intracellular compartment refers to the fluid within cells.
B. The extracellular compartment refers to the fluid outside of cells; extracellular fluid is subdivided into plasma (the fluid portion of the blood) and tissue (interstitial) fluid.
A battery of questions collectively titled Review Activities follows each chapter summary. These self-examinations are organized into three increasingly difficult learning levels to help students progress from simple memorization to higher levels of understanding.
• Test Your Knowledge of Terms and Facts is a series of multiple-choice questions that prompt students to recall key terms and facts presented in the chapter. Answers to these questions are found in Appendix B.
• Test Your Understanding of Concepts and Principles consists of brief essay questions that require students to demonstrate their understanding of chapter material.
• Test Your Ability to Analyze and Apply Your Knowledge questions stimulate critical thinking by challenging students to utilize chapter concepts to solve a problem.
McGraw-Hill offers various tools and technology products to support the eighth edition of Human Physiology. Students can order supplemental study materials by contacting their campus bookstore. Instructors can obtain teaching aids by calling the McGraw-Hill Customer Service Department at 1-800-338-3987, visiting our A&P catalog at www.mhhe.com/ap, or contacting your local McGraw-Hill sales representative.
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