1
Form, Function,
and Life
Chapter Overview
The study of human anatomy and physiology is the study of the forms and processes of the human body. Study of these subjects shows that form and function are closely connected. As organisms, or living things, humans have four characteristics: First, their bodies are organized units, with internal environments kept separate from the external environment in which they live. Second, they rely on metabolism, or chemical reactions, to make the substances they need to function properly. Third, they adapt to their external environment by changing their form, function, or behavior to maintain life and health. Fourth, they are capable of reproduction.
The human body is divided into several systems, each of which carries out basic vital functions. Those systems are composed of a collection of organs, which are, in turn, made of specialized tissues, each of which is composed of cells, which are made of smaller molecules, which are formed of the building blocks of every substance, called atoms.
The human body has five necessities that must be met for survival. First is pressure. The body must exist in the correct atmospheric pressure to allow gases to remain dissolved in the bloodstream; in addition, the body must maintain the proper level of fluid pressure within itself. Second is oxygen, which cells require to live and function. Third is heat, which the body tries to maintain in extreme conditions through adaptations such as shivering. The fourth necessity is nutrients, which the body burns for energy or uses to build structures, and the fifth is water, which aids in several different physical processes.
Gradients, the difference in values in adjacent areas, affect physiological processes.
Substances tend to move from higher levels, whether pressure or concentrations, to lower ones. This principle explains such processes as the flow of blood inside blood vessels and bleeding.
The body adjusts its processes to bring itself back to homeostasis, the range of values for a given process that allows normal, healthy functioning to occur. Each process has a set point, which is the value the body must maintain for optimal health. Negative feedback helps restore a value to its set point by invoking a response opposite to the disruption. Sensors in the body detect changing conditions. They notify an integrating center, which puts
When blood pressure falls too low, for instance, the heart can beat faster to increase the pressure. A few functions are regulated by positive feedback, in which processes intensify until they reach an end point—a new value distinct from the original value. For example, childbirth results from positive feedback, as the effectors increase the condition, rather than working to reduce it.
Anatomy and physiology employ very specific language based on Latin and Greek word parts. Use of this specific language prevents miscommunication among health care
practitioners. Some of the terms relate to different planes chosen for analyzing the body and directions along those planes. Others apply to specific features or areas of the body. Some terms are used to refer to diseases or conditions of the body.
1. Explain the difference between anatomy and physiology
and offer an example of each.
Exercise 1.1
Review the case study that opened the chapter in the textbook. On the spaces below, use details from the case study to explain the difference between anatomy and physiology and give two examples of each.
2. List four characteristics of living things.
Exercise 1.2
In the chart below, state each of the four characteristics of living things and give one example of each from human anatomy and physiology.
Characteristics Examples
1. 1.
2. 2.
3. 3.
3. Within a specific organ system, list the building blocks of life,
starting with the smallest.
Exercise 1.3
Write the names of the six building blocks of body systems, placing each name on the numbered line corresponding to the number in Figure 1.1. After each name, describe the building block or give further details about it.
6 5 3 2 1 4 Figure 1.1 1. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 2. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________
3. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 4. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 5. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 6. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________
4. Identify five features of the external environment
that are necessary for life.
Exercise 1.4
Identify the five characteristics of the external environment that are necessities for life. For each one, explain why it is vital for life.
1. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 2. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 3. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 4. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ 5. ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________
5. Explain the importance of pressure and concentration
gradients in the body.
Exercise 1.5
Study Figures 1.2 and 1.3. Then complete the chart that follows to describe two important types of gradients.
Figure 1.2 Figure 1.3
Type Direction of Flow Along Gradient Significance of Gradient
Figure 1.2
6. Define homeostasis, and 7. Give at least one contribution
of the eleven body systems to homeostasis.
Exercise 1.6
Using the lines below, explain in your own words what homeostasis is and what role it plays in human physiology. Then, in the chart that follows, identify one contribution that each major body system makes to homeostasis.
Definition of homeostasis: __________________________________________________________________________________
Role in human physiology: __________________________________________________________________________________
Body System Contribution to Homeostasis
Integumentary system Skeletal system Muscular system Nervous system Hematopoietic/ cardiovascular system Lymphatic/ immune system (continued)
8. Compare and contrast positive and negative feedback
and offer an example of each.
Exercise 1.7
Choosing from the terms listed below, fill the correct terms into each space. (Note: Some terms may be used more than once; some terms may need to be pluralized.)
condition negative feedback
effector positive feedback
end point sensor
integrating center set point intensify
Body System Contribution to Homeostasis
Respiratory system Digestive system Endocrine system Urinary system Reproductive system
(continued)
In both negative and positive feedback systems, the sequence of events is similar. When
(1) in the internal or external environment change, a(n)
(2) detects the change. The sensor transmits a message
about this change to a(n) (3) , sometimes the brain, which
instructs a(n) (4) to respond. This response might
instruct an organ to function differently in order to bring the body back toward a stable, healthy
Figure 1.4
9. Use anatomic terms to describe different body regions and their
positions relative to one another.
Exercise 1.8
Study the drawings in Figures 1.4 to 1.8. Identify the correct directional term indicated by each circled number. Using the list below, write the correct term in the numbered space.
anterior lateral deep posterior distal proximal inferior superficial medial superior 1. ____________________________________________________________________________________________ 2. ____________________________________________________________________________________________ 3. ___________________________________________________________________________________________ 4. ___________________________________________________________________________________________ 2 1 3 4
might be to increase the heartbeat or to narrow arterial passages, both of which would increase
blood pressure. Responses of this type are examples of (6) .
In the case of (7) , the response differs. In these
conditions, such as childbirth, the response will (8) until
the body reaches a(n) (9) . Of these two types of
homeostatic responses, (10) is more common.
5. _____________________________________________________________________________________ 6. _____________________________________________________________________________________ 7. _____________________________________________________________________________________ 8. _____________________________________________________________________________________ 9. ________________________________________________________________________________________ 10. ________________________________________________________________________________________
Exercise 1.9
Identify the correct location of each body part, as described, by underlining or drawing a circle around the correct term in each boldfaced pair. Assume that the body is in the anatomical position.
1. The fingertips are distal/proximal compared with the wrist. 2. The thumb is lateral/medial compared with the pinky. 3. The chest is inferior/superior to the knee.
4. A deep/superficial cut is more serious than a deep/superficial cut. 5. The buttocks are anterior/posterior to the groin.
6. The heart is lateral/medial compared with the lungs. 7. The groin is inferior/superior to the shoulder.
8. The kneecap is anterior/posterior and distal/proximal compared with the heel.
5 6 7 8 8 7 10 9 Figure 1.7 Figure 1.8 Figure 1.6
2 11 13 4 6 7 1 10 12 14 9 3 5 8 Figure 1.9
Exercise 1.10
Study Figure 1.9. Choosing from the terms in the list below, write the correct name of each body location in the space provided.
brachial occipital cervical patellar digital scapular femoral sternal gluteal tarsal lumbar umbilical nasal vertebral
10. Describe the membranes and list some organs found
in each body cavity.
4 3 2 1 5 8 7 6 Figure 1.11
Part B. Underline each of the structures below with the same color you used in Part A to identify
the cavity in which the structure is found.
brain stomach
heart liver
large intestine ovaries
lungs spinal cord
Exercise 1.12
Write the names of the membranes and cavities in the space provided. Hint: structures 2 and 8 are cavities, and structures 4 and 7 are deep to structures 3 and 6.
1 3 5 2 4 6 Figure 1.10
11. Identify signs and symptoms found in the case study.
Exercise 1.13
Review the case study at the beginning of the chapter in the textbook. Fill in the following chart with four examples of signs and two symptoms from the time the president was shot until his first evaluation at the hospital.
Signs Symptoms
Testing Your Knowledge
Building Understanding
I. Multiple Choice
Select the best answer and circle the letter of your choice.
1. Each of these is a characteristic of all living organisms except
a. adaptation b. movement c. metabolism d. reproduction
2. Which of these lists the components of an organism in the correct order, from smallest
to largest?
a. atom, cell, molecule, tissue, system, organ b. molecule, atom, cell, tissue, organ, system c. atom, molecule, cell, tissue, organ, system d. cell, molecule, atom, organ, tissue, system
3. Each of the following will work to decrease blood pressure except
a. narrowing of arteries b. bleeding
c. slower heartbeat d. weaker heartbeat
4. The flow of blood from a wound is an example of what kind of gradient?
a. altitude b. concentration c. pressure d. systemic
5. Which of these elements of a feedback loop are in the correct order?
a. sensor, integrating center, effector, condition b. condition, sensor, integrating center, effector c. effector, condition, sensor, integrating center d. integrating center, sensor, effector, condition
6. Which of these is not part of the standard anatomical position?
a. standing b. facing forward c. arms crossed d. feet parallel
7. Otitis is an inflammation of which part of the body?
a. arm b. ear c. knee d. nose
8. A patient reports to a physician’s office with sunburn on the middle of his upper back.
Which of these descriptions correctly locates this burn?
a. dorsal, medial, posterior, superficial b. abdominal, lateral, dorsal, superior c. scapular, proximal, anterior, inferior d. sternal, distal, ventral, deep
9. Were you to take an image of the head from the nose to the back of the head, what kind
of section would you be taking?
a. frontal b. oblique c. sagittal d. transverse
10. In which cavity are the lungs located?
a. abdominal b. cranial c. spinal d. thoracic
11. Identifying the cause of a disease means finding its
a. etiology b. lesion c. anatomy d. pathology
II. Completion
Write the word or phrase that correctly completes each sentence.
1. Body structures such as limbs and major joints, which can be seen with the naked eye,
are the object of anatomy.
2. Tree bark, like skin, protects the organism’s internal environment from harm by
functioning as a(n) .
3. The characteristic of organisms that refers to changes in form, function, and behavior in
response to the environment is .
4. Organs that work together to carry out a process are part of a body .
5. The difference between the quantity or the concentration of a physical value in two areas
is called a(n) .
6. The body’s effort to maintain the internal environment within its range of proper
functioning is called .
7. The sequence of events that work to maintain body functions near their set point is called
.
8. The value at which a condition must be maintained for optimal health, such as a body
temperature of 98.6°, is its .
9. A skin abrasion would best be described as .
11. The plane that divides the body into left and right is the
.
12. The part of the body commonly called the leg is more properly referred to as the
.
13. The layer of the pericardium or the pleurae that attaches to the heart or lungs,
respectively, is called the .
14. The pericardial sac, with the heart within, plus the veins and arteries near the heart,
the lower trachea, and other structures, all sit within a space called the .
15. Peritonitis, an inflammatory disease, affects the membrane that surrounds
the .
16. A nurse or a physician takes temperature and blood pressure to determine
measurable signs after a patient complains of certain .
Understanding Concepts
I. True/False
For each question, write T for true or F for false in the blank to the left of each number. If a statement is false, correct it by replacing the underlined term and writing the correct statement in the blank below the question.
________ 1. The purpose of anatomy is to understand the body’s processes.
_________________________________________________________________________________________________
________ 2. The pancreas, liver, and gallbladder are all parts of the digestive system.
_________________________________________________________________________________________________
________ 3. Cells in the body need oxygen to produce the energy needed to live.
________ 4. Pressure moves in a gradient from low to high.
_________________________________________________________________________________________________
________ 5. A positive feedback system works toward a set point.
_________________________________________________________________________________________________
________ 6. The parietal layer of the pericardium attaches to the cavity wall.
_________________________________________________________________________________________________
________ 7. Influenza is a chronic disease.
_________________________________________________________________________________________________
________ 8. Pathology is the study of the physical changes that result from disease.
_________________________________________________________________________________________________
II. Practical Applications
Study the information in each of the following scenarios. Then write the appropriate word in the space provided.
Scenario 1
Maria arrives at the emergency clinic complaining of fatigue and joint pain lasting several days. She also has a headache and a runny nose. A nurse takes her oral temperature and finds it to be 100.2°F (normal 98.6°F). Her blood pressure is 120 mm Hg (normal 120 mm Hg), and her
heartbeat is 95 beats per minute (normal 70 beats per minute).
1. Maria’s tiredness, joint pain, headache, and runny nose are all examples of .
2. To take the woman’s temperature orally, the nurse placed the thermometer in Maria’s
.
3. If she had taken an axillary temperature, the nurse would have placed the thermometer under
Maria’s .
4. Maria’s temperature, blood pressure, and heartbeat are all direct, measurable observations.
These observations are called .
5. Maria’s temperature is higher than normal. Readings that are not normal are said to be
6. After reviewing the charts and examining Maria, the physician suspected a viral infection.
Determining the cause of a disease is looking for its .
7. If the physician could not find the cause, the disease would be considered .
8. The physician prescribes an antiviral medication to support the work of one of Maria’s own
body systems. The system that fights disease is the .
9. Maria’s natural response to fight the disease is part of her body’s effort to restore the state of
normal functioning called .
Scenario 2
Two patients are taken by ambulance to the emergency room after an auto accident. Rick has a crushed left orbital bone and fractured nasal bone, superficial facial cuts, deep lacerations to the left superior thoracic area, and broken bones in the left carpal and digital areas. Both of Rick’s patellas have been crushed, and there is heavy bleeding in the left femoral area. Systolic blood pressure is 85 mm Hg (normal 120 mm Hg), heartbeat 98 beats per minute (normal 70 beats per minute), and respiration rate 40 breaths per minute (normal 14 breaths per minute). Rick is unconscious and does not respond to questions. The other patient, Rachel, has sternal, right olecranal, and right upper brachial bone fractures and complains of lumbar pain. Rachel’s systolic blood pressure is 115 mm Hg (normal 120 mm Hg), heartbeat 75 beats per minute (normal 70 beats per minute), and respiration rate 20 breaths per minute (normal 14 breaths per minute).
1. The crushed left orbital bone suffered by Rick is near his .
2. The fractured nasal bone is on Rick’s .
3. Of the cuts on the superior areas of Rick’s body, the most serious are those in the thoracic area,
or the .
4. Heavy bleeding is coming from Rick’s .
5. Rick’s broken carpal and digital bones affect his and .
6. Unlike Rick, Rachel is conscious and can detail complaints, or .
7. The patient with two broken kneecaps is .
8. The patient whose vital signs (blood pressure, heart rate, and respiration rate) are closest to
III. Short Essays
1. Rocks are made of atoms that form molecules. Why are rocks not considered to be organisms?
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
2. Explain how the functions of an astronaut’s pressure suit demonstrate three necessities of life.
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
3. Using the example of body temperature, explain how homeostasis works to place the body
within a range of values rather than a single specific point.
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
IV. Conceptual Thinking
1. Explain how eating is an example of a negative feedback response. Be sure to use all of the
ele-ments of a negative feedback response in your answer.
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
2. Explain why health care providers use technical terms to describe anatomy, physiology, disease,
and treatment steps.
___________________________________________________________________________________________________________
___________________________________________________________________________________________________________
Expanding Your Horizons
Concerns about the supply of blood needed for transfusions have prompted some companies to try to develop blood substitutes—synthetic products that can be used for trauma patients. Officials in the defense department are particularly interested, as they believe that such a product—which would not need to be refrigerated and would be more portable than regular plasma—could help save lives in combat zones.
Critical Thinking
As you read more about this issue, consider these questions:
1. What are the potential benefits of synthetic blood? 2. What are the possible drawbacks?
3. Do you think more research should be done in this area? Why or why not?
