Chapter 1 - The Sciences of Anatomy and Physiology - End of Chapter Problems

WHAT DID YOU LEARN? 3 _____________ physiology examines how the heart, blood vessels, and blood function.

Cardiovascular physiology examines the functioning of the heart, blood vessels, and blood. Cardiovascular physiologists examine how the heart pumps the blood, what are the parameters for healthy blood pressure, and details of the cellular exchange mechanisms by which respiratory gases, nutrients, and wastes move between blood and body structures.

WHAT DID YOU LEARN? 12 If a physician makes an incision into the abdomen along the midsagittal plane, superior to the umbilicus and just inferior to the diaphragm, then the skin of the __________ abdominopelvic region was incised.

Epigastric?

WHAT DO YOU THINK? 1 When you digest a meal, what type of metabolic reactions do you think you are utilizing primarily: anabolic or catabolic chemical reactions? Why?

When you digest a meal, you are utilizing primarily catabolic chemical reactions, because the main goal is to break down larger molecules (such as starches in bread) into smaller molecules (such as simple sugars) that can be absorbed.

WHAT DID YOU LEARN? 6 Does a higher level of organization contain all the levels beneath it? Explain.

Yes. It is a structural hierarchy where the higher levels contain all the levels below it.

WHAT DID YOU LEARN? 10 The term antebrachial refers to which body region?

forearm, between elbow and wrist

WHAT DID YOU LEARN? 11 Which body cavity is associated with the lungs, and what are the names of its serous membranes?

pleural cavities - parietal pleura & visceral pleura

What are the two body cavities within the posterior aspect, and what does each cavity contain?

posterior aspect contains cavities that are completely encased in bone and are physically and developmentally different from the ventral cavity. The term dorsal body cavity has been used by others to describe this posterior aspect, but is not used here because of these differences between the ventral cavity and posterior aspect. • cranial cavity is formed by the bones of the cranium, aka endocranium, houses the brain • vertebral canal, which is formed by the bones of the vertebral column, houses the spinal cord.

The term used to describe an appendage structure that is closest to its point of attachment to the trunk is a. distal. b. lateral. c. superior. d. proximal.

proximal

WHAT DID YOU LEARN? 8 What type of plane would separate the nose and mouth into superior and inferior structures?

transverse plane also called a horizontal plane or cross-sectional plane, divides the body or organ into superior (top) and inferior (bottom) parts. If a transverse plane is taken through the middle of the trunk, the superior portion contains the chest and the inferior portion contains the abdomen.

Which body cavity is located inferior to the diaphragm and superior to a horizontal line drawn between the superior edges of the hip bones? a. abdominal cavity b. pelvic cavity c. pleural cavity d. pericardial cavity

• The abdominopelvic cavity may be subdivided into two smaller cavities by a horizontal plane at the level of the superior aspects of the hip bones. The area superior to this plane is the abdominal cavity; the pelvic cavity lies inferior to this plane where it is wedged between the two hip bones. You can locate the division between these two cavities by palpating (feeling for) the superior ridges of your hip bones. The abdominal cavity contains most of digestive system organs, as well as the kidneys and most of the ureters. The pelvic cavity contains the distal part of the large intestine, the remainder of the ureters and the urinary bladder, and the internal reproductive organs.

WHAT DID YOU LEARN? 7 Which organ system is responsible for filtering the blood and removing the waste products of the blood in the form of urine?

Urinary System - Filters the blood to remove waste products and biologically active molecules, concentrates waste products in the form of urine, and expels urine from the body.

WHAT DO YOU THINK? 2 What do you think would happen to your body organs if there were no serous fluid between the parietal and visceral layers?

WHAT DO YOU THINK? If you didn't have the lubricating serous fluid,there would be increased friction and it would be quite painful whenever your organs moved. For example, the illness pleurisy (inflammation of the pleura) makes it very painful to breathe, because the pleural membranes are inflamed and the serous fluid cannot appropriately lubricate the membranes

WHAT DID YOU LEARN? 15 What is the main difference between a homeostatic system regulated by negative feedback versus positive feedback?

Homeostasis is the activity of cells throughout the body to maintain the physiological state within a narrow range that is compatible with life. Homeostasis is regulated by negative feedback loops and, much less frequently, by positive feedback loops. Both have the same components of a stimulus, sensor, control center, and effector; however, negative feedback loops work to prevent an excessive response to the stimulus, whereas positive feedback loops intensify the response until an end point is reached.

What properties are common to all living things?

- Organization. - Metabolism. - Growth and Development. - Responsiveness. - Regulation. - Reproduction.

Your grandmother is being seen by a radiologist to diagnose a possible tumor in her small intestine. Explain to your grandmother what imaging techniques would best determine whether a tumor exists, and which techniques would be inadequate for determining the placement of the tumor.

A computed tomography is a more sophisticated application of x-rays. A patient is slowly moved through a cylindrical, doughnut-shaped machine while low-intensity x-rays are emitted on one side the cylinder, passed through the body, collected by detectors, and then processed and analyzed by a computer. These signals produce an image of the body that is about the thickness of a dime. Continuous thin "slices" can be used to reconstruct a three-dimensional image of the body. Little overlap of organs occurs in these thin sections, and the image is much sharper than one obtained by a conventional x-ray. CT scanning is useful for identifying tumors, aneurysms, kidney stones, cerebral hemorrhages, and other abnormalities. A drawback to CTs is that they expose the patient to higher doses of radiation than a traditional x-ray.

WHAT DID YOU LEARN? 13 List and describe the three components of a homeostatic system, and give examples of each in the human body.

A negative feedback system has three basic components (Figure 1a). A sensor, also referred to a receptor, is a component of a feedback system that monitors a physiological value. This value is reported to the control center. The control center is the component in a feedback system that compares the value to the normal range. If the value deviates too much from the set point, then the control center activates an effector. An effector is the component in a feedback system that causes a change to reverse the situation and return the value to the normal range. Body temp exceeds 37 deg C -> nerve cells in skin (receptor) -> Temp regulator in the brain (control center) -> sweat glands throughout body (effector)

WHAT DID YOU LEARN? 4 Compare and contrast how anatomists and physiologists describe the small intestine.

ANATOMISTS • Study the small intestine including its relationship to the rest of the body • Focus on the form and structures of the small intestine • Describe the multiple layers in the wall of the small intestine • Study the tissues of the small intestine and the cells that compose them PHYSIOLOGISTS • Focus on the function of the small intestine • Examine how the muscles of the small intestine propel food through the digestive tract • Describe the mechanisms by which different nutrients are broken down • Study the mechanisms by which different nutrients are absorbed ANATOMISTS & PHYSIOLOGISTS • Know form and function of the small intestine are interrelated

WHAT DID YOU LEARN? 5 What does it mean if an organism is "responsive," and how does this characteristic relate to the survival of this organism?

All organisms exhibit responsiveness, which is the ability to sense and react to stimuli (changes in the external or internal environment). A stimulus to the skin of the hands, such as an extremely hot temperature, causes the human to withdraw the hand from the stimulus so as to prevent injury or damage. Responsiveness occurs at almost all levels of organization.

List the levels of organization in a human, starting at the simplest level and proceeding to the most complex. Give an example of a structure in each level.

Anatomists and physiologists recognize several levels of increasingly complex organization in humans, as illustrated in figure 1.2. These levels, from simplest to most complex, are the chemical level, cellular level, tissue level, organ level, organ system level, and organismal level.

WHAT DID YOU LEARN? 2 What is the relationship between anatomy and physiology?

Anatomy is the study of the body's structures, while physiology is the study of the chemistry and physics of the structures of the body and the ways in which they work together to support the functions of life. They both typically specialize in a particular branch or subdivision. They are inter-related in that one can not study one without an understanding of the other.

WHAT DID YOU LEARN? 1) What subdiscipline of anatomy may explore how the lower limb differs between humans and chimpanzees?

Comparative anatomy examines similarities and the differences in the anatomy of different species. For example, a comparative anatomy class may examine limb structure in humans, chimps, dogs, and cats.

Describe the body in the anatomic position. Why is the anatomic position used?

Descriptions of any body region or part require a common initial point of reference. Note that terms such as "superior" and "inferior" can be relative terms. For example, when a person is standing it would be accurate to say "the heart is superior to the stomach," yet if that person is lying down in a supine position, this statement would seem not to be true. For accuracy and clarity, anatomists and physiologists describe these parts based on the premise that the body is in what is termed the anatomic position, which is then the point of common reference. An individual in the anatomic position stands upright with the feet parallel and flat on the floor, the upper limbs are at the sides of the body, and the palms face anteriorly (toward the front); the head is level, and the eyes look forward toward the observer (figure 1.4). All of the anatomic and directional terms used in this book refer to the body in anatomic position.

WHAT DID YOU LEARN? 16 What is an example of a disease process by which homeostasis is disrupted?

Grave's Disease First, you have to know what is homeostasis. Homeostasis is the regulation of the internal environment of the human body to maintain its balance. That means that the temperature should be regulated, blood should be regulated and this is actually very important since through blood many substances are filtered in and out of the body and transported. Ions must be regulated etc. So, in order for that to happen there are certain mechanism. The endocrine system is one of those, which brings us back to the topic, Grave's disease. Grave's disease is an autoimmune disease of the thyroid gland. The thyroid gladn is the largest endocrine gland in the human body, so imagine what can happen to homeostasis if its normal function is disrupted. What happens with Grave's disease is that this gland becomes overactive producing too many hormones. Since hormones help regulate the homeostasis of the body, that means that this balance would be lost. Fever or an illness accompanied with a fever Homeostasis, as you may know, is the way your body's metabolism maintains your physiological state (pH, temperature, etc.). Temperature is a good example of something that can kill you if it gets out of control. A high fever can be deadly. Homeostasis is what keeps your body at around 98.6 degrees. A fever symbols that you have an underlying illness that has not been treated and is getting worse. A fever is a temporary increase in your body temperature, often due to an illness. Having a fever is a sign that something out of the ordinary is going on in your body. Diabetes When your glucose (sugar) level is high, it damages blood vessels over time, resulting in decreased perfusion or circulation to affected areas. The high glucose levels also cause damage to nerves, which is what causes eventually diabetic neuropathy, characterized by numbness, tingling in toes, fingers, etc. The high glucose levels also leave one more susceptible to infection, because it causes prime conditions for bacteria to flourish. In fact with diabetes, that's the problem that the glucose cant get into the cell because of lack of or insufficient insulin. (insulin is the thing that enables glucose to enter the cells where it is needed. Not in the blood). Furnthermore, homeostasis can be affected when your sugar levels are extremely high, causing fluid and electrolyte problems. ie: diabetic ketoacidosis.

WHAT DID YOU LEARN? 14 On a cold day, what are some of the strategies the body uses to conserve heat?

In contrast, activation of the brain's heat-gain center by exposure to cold reduces blood flow to the skin, and blood returning from the limbs is diverted into a network of deep veins. This arrangement traps heat closer to the body core and restricts heat loss. If heat loss is severe, the brain triggers an increase in random signals to skeletal muscles, causing them to contract and producing shivering. The muscle contractions of shivering release heat while using up ATP. The brain triggers the thyroid gland in the endocrine system to release thyroid hormone, which increases metabolic activity and heat production in cells throughout the body. The brain also signals the adrenal glands to release epinephrine (adrenaline), a hormone that causes the breakdown of glycogen into glucose, which can be used as an energy source. The breakdown of glycogen into glucose also results in increased metabolism and heat production.

What are the similarities and differences between anatomy and physiology?

Like anatomists, physiologists typically specialize in a particular branch of physiology. For example, neurophysiology is the study of the brain, spinal cord, and nerves and how these work together to perform functions as complex and diverse as vision, movement, and thinking. Physiologists may work from the organ level (exploring, for example, what different parts of the brain do) to the molecular level (such as exploring how an electrochemical signal travels along nerves). Form is closely related to function in all living things. For example, the thin flap of your eyelid can snap down to clear away dust particles and almost instantaneously slide back up to allow you to see again. At the microscopic level, the arrangement and function of the nerves and muscles that serve the eyelid allow for its quick action and retreat. At a smaller level of analysis, the function of these nerves and muscles likewise relies on the interactions of specific molecules and ions. Even the three-dimensional structure of certain molecules is essential to their function. Your study of anatomy and physiology will make more sense if you continually relate the form of the structures you are studying to their function. In fact, it can be somewhat frustrating to attempt to study anatomy without an understanding of the physiology that a body structure supports. Imagine, for example, trying to appreciate the unique arrangement of the bones of the human hand if you had no conception of the function of the hand. Fortunately, your understanding of how the human hand manipulates tools—from pens to cell phones—helps you appreciate the unique alignment of the thumb in opposition to the four fingers, making your hand a structure that allows you to pinch and grasp objects and type text messages.

What are the main components in a homeostatic control system?

Maintained by utilizing homeostatic control systems: - receptor, - control center, - and effector

Carly was stung by a bee and was taken to the emergency room because she was undergoing anaphylactic shock (e.g., her breathing became more rapid and more difficult, her heartbeat increased). She was given a shot of epinephrine, which reduced her allergic reactions and brought her breathing and heartbeat back to normal. Did the dose of epinephrine result in a negative feedback mechanism occurring, or a positive feedback mechanism occurring? Explain your answer.

Negative Feedback. Reduced the symptoms due to her allergic reactions.

List the anatomic term that describes each of the following regions: forearm, wrist, chest, armpit, thigh, and foot.

antebrachial, carpal, pectoral, axillary, femoral, pes

Describe the structure and function of serous membranes in the body.

a continuous layer of cells, that encase the subdivisions of the ventral cavity (1) a parietal layer that typically lines the internal surface of the body wall and (2) a visceral layer that covers the external surface of the organs (collectively the viscera) within that cavity. serous cavity - space between the parietal and visceral serous membrane layers serous fluid - secreted by serous membrane within the serous cavity; has the consistency of oil and serves as a lubricant. In a living human, organs (e.g., heart, lungs, intestines) are moving and rubbing against each other and the body wall. Friction caused by this movement is reduced by the serous fluid so the organs move more smoothly against one another and the body walls. Serous membranes will be discussed again in section 5.5b.

The term refers to the sum of all chemical reactions in the body. a. metabolism b. responsiveness c. stimulus d. reproduction

a. metabolism

The region is the anterior part of the knee. a. patellar b. popliteal c. pes d. inguinal

a. patellar

Examining the superficial anatomic markings and internal body structures as they relate to the covering skin is called a. regional anatomy. b. surface anatomy. c. pathologic anatomy. d. comparative anatomy.

a. regional anatomy. Regional anatomy examines all of the structures in a particular region of the body as a complete unit. Most medical school gross anatomy courses are taught using a regional anatomy approach.

A friend just started taking Zoloft (an SSRI) and is experiencing an upset stomach and diarrhea. Your friend asks if the drug is causing her symptoms and you respond: a. Yes, because the drug is irritating her stomach lining and that explains her symptoms. b. Yes, because serotonin is located both in the brain and the digestive tract, so the drug is altering digestive system functioning. c. No, because the drug is supposed to elevate mood and affect brain function, and it shouldn't have any effect on the digestive system. d. No, because the drug is quickly absorbed from the digestive tract and does not remain in the digestive system long enough to have any effect there.

b. Yes, because serotonin is located both in the brain and the digestive tract, so the drug is altering digestive system functioning.

The state of maintaining a constant internal environment within an organism is called a. reproduction. b. homeostasis. c. imbalance. d. life.

b. homeostasis- refers to the ability of an organism to maintain consistent internal environment, or "steady state," in response to changing internal or external conditions. - In this section, we introduce you to the general concept of homeostasis. - We describe the general components of homeostatic systems, - provide specific examples of these regulatory processes, - and then describe the relationship of homeostasis, health, and disease.

When you are outside on a hot, humid day, what body changes occur to help your body temperature return to normal? a. The blood vessels in your skin constrict. b. The sweat glands release sweat. c. Nerve impulses are sent to muscles to cause shivering. d. The smooth muscle associated with hair follicles contracts, causing goose bumps.

b. the sweat glands release sweat

The level of organization is composed of two or more tissue types that work together to perform a common function. a. cellular b. molecular c. organ d. organismal

c. organ

A midsagittal plane separates the body into a. anterior and posterior portions. b. superior and inferior portions. c. right and left halves. d. unequal right and left portions.

c. right and left halves

In a negative feedback mechanism, which of the following events does not occur? a. A stimulus is a change in some variable (e.g., rise in blood glucose levels). b. A receptor perceives a stimulus. c. The control center sends output to an effector. d. The effector stimulates or increases the stimulus, so the cycle continues.

d. The effector stimulates or increases the stimulus, so the cycle continues.

The is the serous membrane layer that covers the surface of the lungs. a. parietal pleura b. visceral pericardium c. visceral peritoneum d. visceral pleura

d. visceral pleura • The right and left sides of the thoracic cavity house the lungs, which are associated with a two-layered serous membrane called the pleura (plˉur′˘ a; = a rib) (figure 1.9c). The parietal pleura is the outer layer of the serous membrane and lines the internal surface of the thoracic wall. The inner layer is the visceral pleura, which covers the external surface of each lung. The pleural cavity is the potential space between these parietal and visceral layers, and it contains serous fluid.

Name the organ systems in the human body.

• The human body contains 11 organ systems: integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, urinary, digestive, and reproductive. Integumentary System Provides protection, regulates body temperature, site of cutaneous receptors and some glands, synthesizes vitamin D, prevents water loss. Skeletal System Provides support and protection, site of hemopoiesis (blood cell production), stores calcium and phosphorus, provides sites for muscle attachments. Muscular System Produces body movement, generates heat when muscles contract. Nervous System A regulatory system that controls muscles and some glands and responds to sensory stimuli. Also responsible for consciousness, intelligence, memory Endocrine System Consists of glands and cell clusters that secrete hormones, which regulate development, growth and metabolism; maintain homeostasis of blood composition and volume, control digestive processes, and control reproduction. Cardiovascular System Consists of the heart and blood vessels; the heart moves blood through blood vessels in order to distribute hormones, nutrients, gases, and pick up waste products. Lymphatic System Transports and filters lymph (interstitial fluid transported through lymph vessels) and participates in an immune response when necessary. Respiratory System Responsible for exchange of gases (oxygen and carbon dioxide) between blood and the air in the lungs. Urinary System Filters the blood to remove waste products and biologically active molecules, concentrates waste products in the form of urine, and expels urine from the body. Digestive System Mechanically and chemically digests food materials, absorbs nutrients, and expels waste products. Male Reproductive System Produces male sex cells (sperm) and male hormones (e.g., testosterone), transfers sperm to the female. Female Reproductive System Produces female sex cells (oocytes) and female hormones (e.g., estrogen and progesterone), receives sperm from male, site of fertilization of oocyte, site of growth and development of embryo and fetus, produces and secretes breast milk for nourishment of newborn.