critical thinking questions about the nervous system

12.1 Structure and Function of the Nervous System

Learning objectives.

By the end of this section, you will be able to:

Relate the anatomical structures to the basic functions of the nervous system.

• Identify the anatomical and functional divisions of the nervous system
• List the basic functions of the nervous system

The Central and Peripheral Nervous Systems

The picture you have in your mind of the nervous system probably includes the brain , the nervous tissue contained within the cranium, and the spinal cord , the extension of nervous tissue within the vertebral column. Additionally, the nervous tissue   that reach out from the brain and spinal cord to the rest of the body ( nerves)  are also part of the nervous system. We can anatomically divide the nervous system into two major regions: the  central nervous system (CNS) is the brain and spinal cord, the peripheral nervous system (PNS) is the nerves ( Figure 12.1.1 ). The brain is contained within the cranial cavity of the skull, and the spinal cord is contained within the vertebral canal of the vertebral column. The peripheral nervous system is so named because it is in the periphery—meaning beyond the brain and spinal cord.

Functional Divisions of the Nervous System

In addition to the anatomical divisions listed above, the nervous system can also be divided on the basis of its functions. The nervous system is involved in receiving information about the environment around us (sensory functions, sensation ) and generating responses to that information (motor functions, responses ) and coordinating the two ( integration ).

Sensation . Sensation refers to receiving information about the environment, either what is happening outside (ie: heat from the sun) or inside the body (ie: heat from muscle activity). These sensations are known as stimuli (singular = stimulus ) and different sensory receptors are responsible for detecting different stimuli. Sensory information travels towards the CNS through the PNS nerves in the specific division known as the afferent (sensory) branch of the PNS. When information arises from sensory receptors in the skin, skeletal muscles, or joints, it is transmitted to the CNS using somatic sensory neurons; when information arises from sensory receptors in the blood vessels or internal organs, it is transmitted to the CNS using visceral sensory neurons.

Response. The nervous system produces a response in effector organs (such as muscles or glands) due to the sensory stimuli. The motor ( efferent ) branch of the PNS carries signals away from the CNS to the effector organs. When the effector organ is a skeletal muscle, the neuron carrying the information is called a somatic motor neuron; when the effector organ is cardiac or smooth muscle or glandular tissue, the neuron carrying the information is called an autonomic motor neuron. Voluntary responses are governed by somatic motor neurons and involuntary responses are governed by the autonomic motor neurons, which are discussed in the next section.

Integration . Stimuli that are detected by sensory structures are communicated to the nervous system where information is processed. In the CNS, information from some stimuli is compared with, or integrated with, information from other stimuli or memories of previous stimuli. Then, a motor neuron is activated to initiate a response from the effector organ. This process during which sensory information is processed and a motor response generated is called integration (see Figure 12.1.2 below).

Chapter Review

The nervous system can be separated into divisions on the basis of anatomy and physiology. The anatomical divisions are the central and peripheral nervous systems. The CNS is the brain and spinal cord. The PNS is everything else and includes afferent and efferent branches with further subdivisions for somatic, visceral and autonomic function. Functionally, the nervous system can be divided into those regions that are responsible for sensation, those that are responsible for integration, and those that are responsible for generating responses.

Review Questions

Critical thinking questions.

1. What responses are generated by the nervous system when you run on a treadmill? Include an example of each type of tissue that is under nervous system control.

2. When eating food, what anatomical and functional divisions of the nervous system are involved in the perceptual experience?

Answers for Critical Thinking Questions

• Running on a treadmill involves contraction of the skeletal muscles in the legs (efferent somatic motor), increase in contraction of the cardiac muscle of the heart (efferent autonomic motor), and the production and secretion of sweat in the skin to stay cool (sensation of temp = afferent visceral sensory, sweat gland activation = efferent autonomic motor).
• The perceptual experience of eating food refers to tasting food, both in terms of flavors and texture. The neurons responsible for sensing taste are afferent somatic neurons of the PNS.

This work, Anatomy & Physiology, is adapted from Anatomy & Physiology by OpenStax , licensed under CC BY . This edition, with revised content and artwork, is licensed under CC BY-SA except where otherwise noted.

Images, from Anatomy & Physiology by OpenStax , are licensed under CC BY except where otherwise noted.

Access the original for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction .

Anatomy & Physiology Copyright © 2019 by Lindsay M. Biga, Staci Bronson, Sierra Dawson, Amy Harwell, Robin Hopkins, Joel Kaufmann, Mike LeMaster, Philip Matern, Katie Morrison-Graham, Kristen Oja, Devon Quick, Jon Runyeon, OSU OERU, and OpenStax is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License , except where otherwise noted.

The Endocrine System

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• 1 - Introduction
• 2 - An Overview of the Endocrine System
• 3 - Hormones
• 4 - The Pituitary Gland and Hypothalamus
• 5 - The Thyroid Gland
• 6 - The Parathyroid Glands
• 7 - The Adrenal Glands
• 8 - The Pineal Gland
• 9 - Gonadal and Placental Hormones
• 10 - The Endocrine Pancreas
• 11 - Organs with Secondary Endocrine Functions
• 12 - Development and Aging of the Endocrine System
• 13 - Key Terms
• 14 - Chapter Review
• 15 - Interactive Link Questions
• 16 - Review Questions
• 17 - Critical Thinking Questions
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Critical Thinking Questions

Describe several main differences in the communication methods used by the endocrine system and the nervous system.

Compare and contrast endocrine and exocrine glands.

True or false: Neurotransmitters are a special class of paracrines. Explain your answer.

Compare and contrast the signaling events involved with the second messengers cAMP and IP 3 .

Describe the mechanism of hormone response resulting from the binding of a hormone with an intracellular receptor.

Compare and contrast the anatomical relationship of the anterior and posterior lobes of the pituitary gland to the hypothalamus.

Name the target tissues for prolactin.

Explain why maternal iodine deficiency might lead to neurological impairment in the fetus.

Define hyperthyroidism and explain why one of its symptoms is weight loss.

Describe the role of negative feedback in the function of the parathyroid gland.

Explain why someone with a parathyroid gland tumor might develop kidney stones.

What are the three regions of the adrenal cortex and what hormones do they produce?

If innervation to the adrenal medulla were disrupted, what would be the physiological outcome?

Compare and contrast the short-term and long-term stress response.

Seasonal affective disorder (SAD) is a mood disorder characterized by, among other symptoms, increased appetite, sluggishness, and increased sleepiness. It occurs most commonly during the winter months, especially in regions with long winter nights. Propose a role for melatonin in SAD and a possible non-drug therapy.

Retinitis pigmentosa (RP) is a disease that causes deterioration of the retinas of the eyes. Describe the impact RP would have on melatonin levels.

Compare and contrast the role of estrogens and progesterone.

Describe the role of placental secretion of relaxin in preparation for childbirth.

What would be the physiological consequence of a disease that destroyed the beta cells of the pancreas?

Why is foot care extremely important for people with diabetes mellitus?

Summarize the role of GI tract hormones following a meal.

Compare and contrast the thymus gland in infancy and adulthood.

Distinguish between the effects of menopause and andropause on fertility.

15 Parts of the Nervous System

[latexpage]

Learning Objectives

By the end of this section, you will be able to:

• Describe the difference between the central and peripheral nervous systems
• Explain the difference between the somatic and autonomic nervous systems
• Differentiate between the sympathetic and parasympathetic divisions of the autonomic nervous system

The nervous system can be divided into two major subdivisions: the central nervous system (CNS) and the peripheral nervous system (PNS) , shown in [link] . The CNS is comprised of the brain and spinal cord; the PNS connects the CNS to the rest of the body. In this section, we focus on the peripheral nervous system; later, we look at the brain and spinal cord.

Peripheral Nervous System

The peripheral nervous system is made up of thick bundles of axons, called nerves, carrying messages back and forth between the CNS and the muscles, organs, and senses in the periphery of the body (i.e., everything outside the CNS). The PNS has two major subdivisions: the somatic nervous system and the autonomic nervous system.

The somatic nervous system is associated with activities traditionally thought of as conscious or voluntary. It is involved in the relay of sensory and motor information to and from the CNS; therefore, it consists of motor neurons and sensory neurons. Motor neurons, carrying instructions from the CNS to the muscles, are efferent fibers (efferent means “moving away from”). Sensory neurons, carrying sensory information to the CNS, are afferent fibers (afferent means “moving toward”). Each nerve is basically a two-way superhighway, containing thousands of axons, both efferent and afferent.

The autonomic nervous system controls our internal organs and glands and is generally considered to be outside the realm of voluntary control. It can be further subdivided into the sympathetic and parasympathetic divisions ( [link] ). The sympathetic nervous system is involved in preparing the body for stress-related activities; the parasympathetic nervous system is associated with returning the body to routine, day-to-day operations. The two systems have complementary functions, operating in tandem to maintain the body’s homeostasis. Homeostasis is a state of equilibrium, in which biological conditions (such as body temperature) are maintained at optimal levels.

The sympathetic nervous system is activated when we are faced with stressful or high-arousal situations. The activity of this system was adaptive for our ancestors, increasing their chances of survival. Imagine, for example, that one of our early ancestors, out hunting small game, suddenly disturbs a large bear with her cubs. At that moment, his body undergoes a series of changes—a direct function of sympathetic activation—preparing him to face the threat. His pupils dilate, his heart rate and blood pressure increase, his bladder relaxes, his liver releases glucose, and adrenaline surges into his bloodstream. This constellation of physiological changes, known as the fight or flight response , allows the body access to energy reserves and heightened sensory capacity so that it might fight off a threat or run away to safety.

Reinforce what you’ve learned about the nervous system by playing this BBC-produced interactive game about the nervous system.

While it is clear that such a response would be critical for survival for our ancestors, who lived in a world full of real physical threats, many of the high-arousal situations we face in the modern world are more psychological in nature. For example, think about how you feel when you have to stand up and give a presentation in front of a roomful of people, or right before taking a big test. You are in no real physical danger in those situations, and yet you have evolved to respond to any perceived threat with the fight or flight response. This kind of response is not nearly as adaptive in the modern world; in fact, we suffer negative health consequences when faced constantly with psychological threats that we can neither fight nor flee. Recent research suggests that an increase in susceptibility to heart disease (Chandola, Brunner, & Marmot, 2006) and impaired function of the immune system (Glaser & Kiecolt-Glaser, 2005) are among the many negative consequences of persistent and repeated exposure to stressful situations.

Once the threat has been resolved, the parasympathetic nervous system takes over and returns bodily functions to a relaxed state. Our hunter’s heart rate and blood pressure return to normal, his pupils constrict, he regains control of his bladder, and the liver begins to store glucose in the form of glycogen for future use. These processes are associated with activation of the parasympathetic nervous system.

The brain and spinal cord make up the central nervous system. The peripheral nervous system is comprised of the somatic and autonomic nervous systems. The somatic nervous system transmits sensory and motor signals to and from the central nervous system. The autonomic nervous system controls the function of our organs and glands, and can be divided into the sympathetic and parasympathetic divisions. Sympathetic activation prepares us for fight or flight, while parasympathetic activation is associated with normal functioning under relaxed conditions.

Review Questions

Our ability to make our legs move as we walk across the room is controlled by the ________ nervous system.

• sympathetic
• parasympathetic
• somatic nervous system
• sympathetic nervous system
• parasympathetic nervous system
• spinal cord

The central nervous system is comprised of ________.

• sympathetic and parasympathetic nervous systems
• organs and glands
• somatic and autonomic nervous systems
• brain and spinal cord
• pupil dilation
• storage of glucose in the liver
• increased heart rate
• both A and C

Critical Thinking Questions

What are the implications of compromised immune function as a result of exposure to chronic stress?

Chronic stress can lead to increased susceptibility to bacterial and viral infections, and potentially an increased risk of cancer. Ultimately, this could be a vicious cycle with stress leading to increased risk of disease, disease states leading to increased stress and so on.

Examine [link] , illustrating the effects of sympathetic nervous system activation. How would all of these things play into the fight or flight response?

Most of these effects directly impact energy availability and redistribution of key resources and heightened sensory capacity. The individual experiencing these effects would be better prepared to fight or flee.

Personal Application Questions

Hopefully, you do not face real physical threats from potential predators on a daily basis. However, you probably have your fair share of stress. What situations are your most common sources of stress? What can you do to try to minimize the negative consequences of these particular stressors in your life?

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7.2.10: Critical Thinking Questions

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How does the polygastric digestive system aid in digesting roughage?

How do birds digest their food in the absence of teeth?

What is the role of the accessory organs in digestion?

Explain how the villi and microvilli aid in absorption.

Name two components of the digestive system that perform mechanical digestion. Describe how mechanical digestion contributes to acquiring nutrients from food.

What are essential nutrients?

What is the role of minerals in maintaining good health?

Discuss why obesity is a growing epidemic.

There are several nations where malnourishment is a common occurrence. What may be some of the health challenges posed by malnutrition?

Generally describe how a piece of bread can power your legs as you walk up a flight of stairs.

In the 1990s fat-free foods became popular among people trying to lose weight. However, many dieticians now conclude that the fat-free trend made people less healthy and heavier. Describe how this could occur.

Explain why some dietary lipid is a necessary part of a balanced diet.

The gut microbiome (the bacterial colonies in the intestines) have become a popular area of study in biomedical research. How could varying gut microbiomes impact a person’s nutrition?

Many mammals become ill if they drink milk as adults even though they could consume it as babies. What causes this digestive issue?

Describe how hormones regulate digestion.

Describe one or more scenarios where loss of hormonal regulation of digestion can lead to diseases.

A scientist is studying a model that has a mutation in the receptor for somatostatin that prevents hormone binding. How would this mutation affect the structure and function of the digestive system?

• Introduction
• 26.1 Neurons and Glial Cells
• 26.2 How Neurons Communicate
• 26.3 The Central Nervous System
• 26.4 The Peripheral Nervous System
• 26.5 Nervous System Disorders
• Chapter Summary
• Review Questions

Critical Thinking Questions

• Test Prep for AP ®  Courses
• Science Practice Challenge Questions

When you stick your hand in a bucket of ice, it grows numb after a while. Based on what you know regarding neuronal signaling, explain how the sensation of touch is blocked from signaling to the brain.

What are the main differences between the sympathetic and parasympathetic nervous systems?

• The sympathetic nervous system is activated by stressful situations, whereas the parasympathetic nervous system resets organ function of sympathetic reactions and allows animals to “rest and digest.”
• The parasympathetic nervous system is activated by stressful situations, whereas the sympathetic nervous system resets organ function of sympathetic reactions and allows animals to “rest and digest.”
• The sympathetic nervous system is involved in unconscious body function control, whereas the parasympathetic nervous system is involved in conscious body function control.
• The parasympathetic nervous system is involved in unconscious body function control, whereas the sympathetic nervous system is involved in conscious body function control.

How is the sensory-somatic nervous system involved in sensing information and motor function?

• The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the peripheral nervous system. Motor information is sent to and from the central nervous system and the muscles.
• The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the central nervous system. Motor information is sent to and from the central nervous system and the muscles.
• The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the central nervous system. Motor information is sent to and from the peripheral nervous system and the muscles.
• The sensory-somatic nervous system transmits information from the skin, muscles, and sensory organs to the peripheral nervous system. Motor information is sent to and from the peripheral nervous system and the muscles.

Public speaking can be very stressful. How can anticipating giving a public speech stimulate the sympathetic nervous system?

• During stress, multiple preganglionic neurons can synapse on one postganglionic neuron, and the adrenal gland releases adrenaline.
• During stress, one preganglionic neuron can synapse on multiple postganglionic neurons, and the thymus gland releases norepinephrine.
• During stress, one postganglionic neuron can synapse on multiple preganglionic neurons, and the adrenal gland releases norepinephrine.
• During stress, one preganglionic neuron can synapse on multiple postganglionic neurons, and the adrenal gland releases norepinephrine.

What might make you suspect that an individual has Alzheimer’s disease?

• disruptive memory loss, confusion about time or place, difficulty with planning and executing tasks, poor judgment, and/or personality changes
• slowed movements, balance and posture problems, rigid muscles, speech changes, and/or psychological symptoms such as dementia
• impaired social skills, repetitive motor behaviors, strict adherence to certain rituals, and preoccupation with specific subjects
• balance and posture problems, repetitive motor behaviors, difficulty with planning and executing tasks, poor judgment, and/or personality changes

What treatment options are available for an individual diagnosed with major depression?

• blood pressure medication, deep-brain stimulation, taking monoamine oxidase inhibitors, psychotherapy, and physical therapy
• psychotherapy, electroconvulsive therapy, deep-brain stimulation, taking monoamine oxidase inhibitors, and/or taking selective melatonin reuptake inhibitors
• psychotherapy, electroconvulsive therapy, deep-brain stimulation, taking monoamine oxidase inhibitors, and/or taking selective serotonin reuptake inhibitors
• blood pressure medication, classes of antipsychotics, psychotherapy, electroconvulsive therapy, deep-brain stimulation, and/or taking selective serotonin reuptake inhibitors

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14.9: Critical Thinking Questions

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The sweetener known as stevia can replace glucose in food. What does the molecular similarity of stevia to glucose mean for the gustatory sense?

Why does the blind spot from the optic disc in either eye not result in a blind spot in the visual field?

Following a motorcycle accident, the victim loses the ability to move the right leg but has normal control over the left one, suggesting a hemisection somewhere in the thoracic region of the spinal cord. What sensory deficits would be expected in terms of touch versus pain? Explain your answer.

A pituitary tumor can cause perceptual losses in the lateral visual field. The pituitary gland is located directly inferior to the hypothalamus. Why would this happen?

The prefrontal lobotomy is a drastic—and largely out-of-practice—procedure used to disconnect that portion of the cerebral cortex from the rest of the frontal lobe and the diencephalon as a psychiatric therapy. Why would this have been thought necessary for someone with a potentially uncontrollable behavior?

If a reflex is a limited circuit within the somatic system, why do physical and neurological exams include them to test the health of an individual?

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• CRITICAL THINKING QUESTIONS

• Describe how the body’s mechanisms maintain homeostasis?
• Why is excretion important in order to achieve osmotic balance?
• What is the role of the accessory organs in digestion?
• What is the role of minerals in maintaining good health?
• Discuss why obesity is a growing epidemic.
• Describe the function of these terms and describe where they are located: main bronchus, trachea, alveoli.
• How does the structure of alveoli maximize gas exchange?
• Describe the cardiac cycle.
• What is a similarity and a difference between an exocrine gland and an endocrine gland?
• Describe how hormone receptors can play a role in affecting the size of the responses of tissues to hormones.
• Many hormone systems regulate body functions through opposing hormone actions. Describe how opposing hormone actions regulate blood-glucose levels?
• What movements occur at the hip joint and knees as you bend down to pick something up?
• How are neurons similar to other cells? How are they unique?
• What are the main functions of the spinal cord?
• What are the main differences between the sympathetic and parasympathetic branches of the autonomic nervous system?
• What are the main functions of the sensorysomatic nervous system?
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• Mechanisms of Evolution
• Evidence of Evolution
• Common Misconceptions about Evolution ART CONNECTION QUESTIONS
• The Levels of Classification Art CONNECTION
• Classification and Phylogeny
• Limitations of Phylogenetic Trees
• Misleading Appearances
• Molecular Comparisons Evolution In Action
• Shared Characteristics
• Choosing the Right Relationships
• Organizing Life on Earth
• Determining Evolutionary Relationships
• Early Life on Earth
• Characteristics of Prokaryotes
• The Cell Wall Art Connection
• How Prokaryotes Obtain Energy and Carbon
• Bacterial Diseases in Humans
• Historical Perspective
• The Antibiotic Crisis
• Foodborne Diseases Careers IN ACTION
• Beneficial Prokaryotes
• Prokaryotes, and Food and Beverages
• Prokaryotes in and on the Body
• Chloroplasts
• Protist Structure
• How Protists Obtain Energy
• Protist Diversity
• Plasmodium Species
• Trypanosomes
• Plant Parasites
• Protists as Food Sources
• Agents of Decomposition
• Growth and Reproduction
• How Fungi Obtain Nutrition
• Fungal Diversity
• Pathogenic Fungi
• Plant Parasites and Pathogens
• Animal and Human Parasites and Pathogens
• Importance to Ecosystems
• Importance to Humans
• Prokaryotic Diversity
• Eukaryotic Origin
• Alternation of Generations
• Sporangia in the Seedless Plants
• Gametangia in the Seedless Plants
• Apical Meristems
• Additional Land Plant Adaptations Evolution IN ACTION
• The Major Divisions of Land Plants
• Vascular Tissue: Xylem and Phloem
• Roots: Support for the Plant
• Leaves, Sporophylls, and Strobili
• Club Mosses
• Ferns and Whisk Ferns Careers IN ACTION
• The Evolution of Seed Plants
• Life Cycle of a Conifer Art Connection
• Gingkophytes
• Gnetophytes
• The Life Cycle of an Angiosperm Art Connection
• Basal Angiosperms
• Comparison of Structural Characteristics of Monocots and Eudicots
• The Plant Kingdom
• Seedless Plants
• Seed Plants: Gymnosperms
• Seed Plants: Angiosperms
• Complex Tissue Structure
• Sexual Reproduction and Embryonic Development
• Asexual Reproduction
• Body Symmetry
• Layers of Tissues
• Presence or Absence of a Coelom
• Protostomes and Deuterostomes
• Physiological Processes in Sponges
• Physiological Processes of Cnidarians
• Cnidarian Diversity
• Physiological Processes of Flatworms
• Diversity of Flatworms
• Physiological Processes of Nematodes
• Physiological Processes of Arthropods
• Arthropod Diversity
• Mollusk Diversity
• Physiological Processes of Annelida
• Annelid Diversity
• Echinoderms
• Physiological Processes of Echinoderms
• Echinoderm Diversity
• Chordates Art CONNECTION
• Invertebrate Chordates
• Jawless Fishes
• Jawed Fishes
• Bony Fishes
• Amphibian Diversity
• Features of the Animal Kingdom
• Sponges and Cnidarians
• Flatworms, Nematodes, and Arthropods
• Mollusks and Annelids
• Echinoderms and Chordates
• Vertebrates
• Thermoregulation Art CONNECTION
• Excretory System Careers IN ACTION
• Oral Cavity
• Small Intestine
• Large Intestine
• Accessory Organs Art CONNECTION
• Nutrition Biology IN ACTION
• The Respiratory System Art CONNECTION
• The Circulatory System
• The Heart Art CONNECTION
• The Cardiac Cycle
• Blood Vessels
• Hormones Career IN ACTION
• How Hormones Work
• Endocrine Glands
• Regulation of Hormone Production Art CONNECTION
• Skeletal System
• Joints and Skeletal Movement Careers IN ACTION
• Skeletal Muscle Fiber Structure and Function
• Neurons and Glial Cells Biology IN ACTION
• How Neurons Communicate
• The Central Nervous System
• Spinal cord
• The Peripheral Nervous System
• Homeostasis and Osmoregulation
• Digestive System
• Circulatory and Respiratory Systems
• Endocrine System
• Musculoskeletal System
• Nervous System
• Steps of Virus Infections Art CONNECTION
• Vaccines for Prevention
• Vaccines and Antiviral Drugs for Treatment
• External and Chemical Barriers
• The Inflammatory Response and Phagocytosis
• Natural Killer Cells
• B and T Cells
• Humoral Immune Response
• Cell-Mediated Immunity
• Immunological Memory Art CONNECTION
• The Lymphatic System
• Mucosal Immune System
• Immune Tolerance
• Immunodeficiency
• Autoimmunity
• Innate Immunity
• Adaptive Immunity
• Disruptions in the Immune System
• Fragmentation
• Parthenogenesis
• Hermaphroditism
• Sex Determination
• Fertilization
• Internal Fertilization
• Organogenesis
• Male Reproductive Anatomy ART CONNECTION
• Female Reproductive Anatomy
• Spermatogenesis
• Male Hormones
• Female Hormones
• The Ovarian Cycle and the Menstrual Cycle Art CONNECTION Careers IN ACTION
• How Animals Reproduce
• Development and Organogenesis
• Human Reproduction
• Estimating Population Size
• Species Distribution
• Life Tables
• Survivorship Curves
• Exponential Growth
• Carrying Capacity and the Logistic Model
• Role of Intraspecific Competition
• Examples of Logistic Growth Art CONNECTIONS
• Population Dynamics and Regulation
• Density-dependent Regulation
• Density-independent Regulation and Interaction with Density-dependent Factors Density-dependent Factors Evolution IN ACTON
• Demographic-Based Population Models
• Overcoming Density-Dependent Regulation
• Age Structure, Population Growth, and Economic Development Art CONNECTION
• Long-Term Consequences of Exponential Human Population Growth

Critical Thinking Questions

Arterioles are often referred to as resistance vessels. Why?

Cocaine use causes vasoconstriction. Is this likely to increase or decrease blood pressure, and why?

A blood vessel with a few smooth muscle fibers and connective tissue, and only a very thin tunica externa conducts blood toward the heart. What type of vessel is this?

You measure a patient’s blood pressure at 130/85. Calculate the patient’s pulse pressure and mean arterial pressure. Determine whether each pressure is low, normal, or high.

An obese patient comes to the clinic complaining of swollen feet and ankles, fatigue, shortness of breath, and often feeling “spaced out.” She is a cashier in a grocery store, a job that requires her to stand all day. Outside of work, she engages in no physical activity. She confesses that, because of her weight, she finds even walking uncomfortable. Explain how the skeletal muscle pump might play a role in this patient’s signs and symptoms.

A patient arrives at the emergency department with dangerously low blood pressure. The patient’s blood colloid osmotic pressure is normal. How would you expect this situation to affect the patient’s net filtration pressure?

True or false? The plasma proteins suspended in blood cross the capillary cell membrane and enter the tissue fluid via facilitated diffusion. Explain your thinking.

A patient arrives in the emergency department with a blood pressure of 70/45 confused and complaining of thirst. Why?

Nitric oxide is broken down very quickly after its release. Why?

Identify the ventricle of the heart that pumps oxygen-depleted blood and the arteries of the body that carry oxygen-depleted blood.

What organs do the gonadal veins drain?

What arteries play the leading roles in supplying blood to the brain?

All tissues, including malignant tumors, need a blood supply. Explain why drugs called angiogenesis inhibitors would be used in cancer treatment.

Explain the location and importance of the ductus arteriosus in fetal circulation.

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Access for free at https://openstax.org/books/anatomy-and-physiology-2e/pages/1-introduction

• Authors: J. Gordon Betts, Kelly A. Young, James A. Wise, Eddie Johnson, Brandon Poe, Dean H. Kruse, Oksana Korol, Jody E. Johnson, Mark Womble, Peter DeSaix
• Publisher/website: OpenStax
• Book title: Anatomy and Physiology 2e
• Publication date: Apr 20, 2022
• Location: Houston, Texas
• Book URL: https://openstax.org/books/anatomy-and-physiology-2e/pages/1-introduction
• Section URL: https://openstax.org/books/anatomy-and-physiology-2e/pages/20-critical-thinking-questions

© Dec 19, 2023 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.