Human Anatomy and Physiology - Chapter 1 Notes

Introduction to Anatomy and Physiology

Science: A method for observing and measuring natural phenomena to explain them. It has significantly improved our understanding of the human body.
Human Anatomy: Study of the structure or form of the human body.
Human Physiology: Study of the body’s functions. The body’s structure and function are closely related.

Core Study Strategies: Bring It Back, Space It Out, and Mix It Up

Bring It Back: Reading or hearing something once encodes the information in short-term or working memory.
- To transfer information to long-term memory, consolidate the material using methods like self-quizzing, flashcards, chapter questions, study guides, or teaching.
- Re-reading leads to familiarity, not necessarily knowledge.
Study Boost: Four Ways to Help You Bring It Back
- Mnemonic devices: Mental cues for memorizing material.
- Concrete Examples: Connect the material to real-world examples.
- Elaborative Questioning: Ask many detailed questions about the material.
- Dual Coding: Use text and figures or drawings together.
Space It Out: Leave time between study sessions to allow some forgetting.
- This forces the brain to reload information, improving consolidation and long-term memory.
Mix It Up: Change study techniques and the order of material.
- Shuffle flashcards or switch between topics.
- Combine with "Space It Out" to mirror natural learning.

How to Use This Book and Its Associated Materials

How to Read a Textbook—The S Q 3 R Method
- Survey: Skim the chapter, noting key terms and figures.
- Question: Form questions about the content or turn Learning Outcomes into questions.
- Read: Read actively, taking notes and making diagrams.
- Recite: Speak aloud while reading.
- Review: Use the three core study strategies.
How to Read A&P Figures
- Examine the figures during the initial chapter survey.
- Identify the concept the figure teaches first.
- Break the figure into parts, and understand each part before moving to the next.
- When you understand each part of the figure, examine it as a whole.
- Combine the figure’s content with that of other figures for a more global understanding
Features of This Book: Chapters are divided into modules covering core concepts.
- Learning Outcomes: List of core concepts and principles to understand.
- Concept Boosts and Study Boosts: Additional explanations and study hints.
- Questions: Include Bring It Back, Quick Check, Apply What You Learned questions, and Assess What You Learned quizzes.
Study Boost: The Many Ways to Use the Learning Outcomes
- Review during the "Survey" portion of the S Q 3 R process.
- Use to generate questions during the "Question" portion.
- Use as a starting point for elaborative questioning.
- Adapt them into a quiz for the "Bring It Back" strategy.
Associated Materials and How to Use Them
- Active-Learning Workbook: Use activities like labeling and drawing.
- Online Practice Tools and Dynamic Study Modules: Use Mastering® A&P with interactive flashcards and quizzes.
- Online Media: Utilize Concept Boost Mini-Lectures, Author-Narrated Podcasts, Big Picture Animations, Practice Anatomy Mastering® Interactive Physiology 2.0, and PhysioEx™.
Open the DOORS to Critical Thinking
- D: Describe the problem—Read carefully.
- O: Do an Overview of the chapter—Concepts from several modules may be required.
- O: Look to Other chapters for pertinent details—Look up the topic in the index.
- R: Review your findings for Relevancy—Discard information that is not relevant.
- S: Synthesize the information into a coherent answer.
How to Make the Best Use of Class Time
- Come Prepared: Read assigned material to make connections during class.
- Use the Cornell Note-Taking System
  - Divide paper into two columns with shared space at the bottom.
  - Write concise notes on the right during lecture.
  - Write questions about the notes on the left after class.
  - Summarize the main points at the bottom.
Studying for Exams
- Managing Your Time
  - Make a schedule and budget your time.
  - Study continuously from the first day.
  - Allow more time than needed.
- Developing a Growth Mindset
  - Failure results from lack of effort or incorrect strategy, not lack of ability.
  - Focus on learning goals rather than performance goals.
- Closing Tips
  - Find out as much as possible about the exam.
  - Use available resources.
  - Form a study group.
  - Take care of yourself and manage stress.
  - Don’t be afraid to ask for help.

Characteristics of Living Organisms

Living Organisms share distinct properties
- Cellular Composition: Cells are the smallest units that carry out life functions.
- Metabolism: Chemical processes collectively called metabolism.
  - Anabolism: "Building" processes.
  - Catabolism: "Breaking down" processes.
- Growth: An increase in the size and/or number of cells
- Excretion: Elimination of potentially harmful waste products of metabolism.
- Responsiveness or Irritability: Organisms sense and react to changes in their environment.
- Movement: Organisms or individual cells of an organism move.
- Reproduction: Production of new cells for growth or repair, or reproduction of new organisms.

Levels of Structural Organization and Body Systems

The body is constructed of a series of progressively larger "building blocks" known as the Structural Levels of Organization
- Chemical Level: This is the smallest level; Chemicals range from tiny atoms to complex molecules
- Cellular Level: Groups of many different types of molecules combine in specific ways to form cellular structures
- Tissue Level: Two or more cell types and material outside them, called extracellular matrix, combine to perform a common function
- Organ Level: Two or more tissue types combine to form an organ with a recognizable shape that performs a specialized task
- Organ System Level: Two or more organs that together carry out a broad function in the body
  - The human body has 11 organ systems
- Organism Level: The organ systems function together to make up the working human body—an organism

Types of Anatomy and Physiology

Study of Anatomy can be approached in several ways
- Systemic Anatomy: Examines individual organ systems
- Regional Anatomy: Examines the body in regions, such as the head and neck
- Surface Anatomy: Examines surface markings
- Gross Anatomy: Examines structures that can be seen with the unaided eye
- Microscopic Anatomy: Examines cells (Cytology) and tissues (Histology) with the use of a microscope
Study of Physiology includes numerous subfields
- Physiology subfields are classified by organ or organ systems, such as neurophysiology and cardiophysiology
- Physiologists can also study other structural levels of organization of the body such as chemical, cellular, and tissue levels

Word Parts

The language of science is built on Word Roots—core components of words with specific meanings
Word roots are combined with Prefixes and Suffixes to yield scientific terms
For example, combine the following:
- Prefix an- (means without)
- Word root encephala- (means brain)
- Suffix -ic (means condition of)
“Anencephalic” is the condition of lacking a part of the brain

The Anatomical Position and Directional Terms

Anatomical Position: Common frame of reference from which all body parts and regions are described regardless of position
- Body is standing upright
- Feet are shoulder width apart
- Upper limbs at the sides of trunk
- Head and palms facing forward
Directional Terms: Describe the relative locations of body parts and markings to ensure accurate communication among scientists and healthcare professionals
- Anterior/Posterior: Anterior refers to the front and posterior refers to the back; Can refer to body as a whole or to a body part
- Superior/Inferior: Superior, or cranial, means towards the head and inferior, or caudal, means towards the tail; Used to refer to positions on head, neck, and trunk only
- Proximal/Distal: Proximal means closer to the point of origin and distal means further from the point of origin; Used to refer to positions on the limbs only
- Medial/Lateral: Medial refers to a position closer to the middle line of the body, called the midline, and lateral refers to a position farther away from the midline
- Superficial/Deep: Superficial refers to structures closer to the surface of the body and deep refers to structures farther below

Medical Errors

Most medical errors occur when a patient is dispensed the wrong type or dose of medication
Occasionally, they involve surgery and are known as “wrong site” or “wrong body” procedures when the surgeon operates on the wrong part of the body or even the wrong patient
Precise communication with appropriate use of anatomical terminology is critical to prevent medical errors

Regional Terms

Regional Terms: The body can be divided into two broad regions: Axial (head, neck, and trunk); and Appendicular (upper and lower limbs or appendages)
- Each broad region can be divided into several smaller Regions
- Regions may be named as nouns, such as the upper arm or brachium, or as adjective with the addition of a suffix such as -al, which is paired with the word “region” to give us the term brachial region
Regional Terms Table
- Region of the Trunk:
  - Abdominal: The abdomen
  - Cervical: The neck
  - Gluteal: The buttocks
  - Inguinal: The groin
  - Lumbar: The lower back
  - Pelvic: The pelvis
  - Pubic: The pubis
  - Sacral: The sacrum
  - Sternal: The sternum
  - Thoracic: The chest
  - Vertebral: The spinal column
- Region of the Head and Face:
  - Buccal: The cheek
  - Cranial: The skull
  - Cephalic: The head
  - Frontal: The forehead
  - Mental: The chin
  - Nasal: The nose
  - Occipital: The back of the head
  - Ocular: The eye
  - Oral: The mouth
  - Otic: The ear
- Region of the Upper Limb:
  - Acromial: The point of the shoulder
  - Antebrachial: The forearm
  - Antecubital: The anterior surface of the elbow
  - Axillary: The armpit
  - Brachial: The arm
  - Carpal: The wrist
  - Digital: The fingers (or toes)
  - Manual: The hand
  - Metacarpal: The metacarpals (bones of the hand)
  - Palmar: The palm
  - Pollex: The thumb
- Region of the Lower Limb:
  - Coxal: The hip
  - Crural: The anterior surface of the leg
  - Femoral: The thigh
  - Hallux: The great toe
  - Metatarsal: The metatarsals (bones of the foot)
  - Patellar: The anterior surface of the knee
  - Pedal: The foot
  - Plantar: The sole of the foot
  - Popliteal: The posterior surface of the knee
  - Sural: The posterior surface of the leg
  - Tarsal: The ankle
    Putting Anatomical Terms Together
- Name the Region—Cervical region
- Add Descriptive Directional Terms— On anterior side, Lateral to midline; Begins inferior to mental region; Ends superior to thoracic region
- Describe Depth of Incision—Deep to skin and muscle; Superficial to underlying larynx
- Put It All Together—Incision on anterior cervical region lateral to midline; Extended vertically 1 centimeter inferior to mental region to 2 centimeters superior to thoracic region; Deep to skin and muscle, but superficial to larynx
- Name the Region—Left Crural
- Add Descriptive Directional Terms— On anterior and medial side; Proximal to tarsal region and distal to patellar region
- Describe Depth of Incision—Deep to skin and muscle but superficial to bone
- Put It All Together—Wound on left anteromedial crural region, 10 centimeters proximal to tarsal region and 6 centimeters distal to patellar region; Pellet is lodged deep to skin and muscle but superficial to bone

Planes of Section

Planes of Section—Divide a body or body part for examination
- Sagittal Plane—Divides body into right and left sections
  - Midsagittal Plane: Also called a Median Plane; Sections are equal
  - Parasagittal Plane: Sections are unequal
- Frontal Plane—Also called a Coronal Plane; Divides body into anterior and posterior sections
- Transverse Plane—Also called a Horizontal Plane or Cross Section; Divides body into superior and inferior sections or proximal and distal sections
- Oblique Plane—Used less frequently; Taken at an angle

Study Boost: How to Learn Anatomical Terms

Flashcards are popular because research shows that they work
- Make customized flashcards with Practice Anatomy Lab™ Flashcards in the Study Area of Mastering® A&P
- Make handwritten flashcards
Don’t forget to “Bring It Back” by quizzing yourself and “Mix It Up” by randomizing the order

The Posterior Body Cavity

Cavity—Any space within the body; Protects internal organs and allows them to move
Posterior Body Cavity— Located on posterior side of body
- Cranial Cavity—Within the skull; Includes the brain
- Spinal Cavity—Within the vertebral column; Includes the spinal cord
- Both cavities are filled with Cerebrospinal Fluid, which bathes both organs

The Anterior Body Cavity

Anterior Body Cavity—Has two main divisions separated by the muscular diaphragm
- Thoracic Cavity is superior to the diaphragm
- Abdominopelvic Cavity is inferior to the diaphragm
- Smaller cavities exist within the thoracic and abdominopelvic cavities formed by sheets of tissue termed Serous Membranes
Anterior Body Cavity
- Thoracic Cavity
  - Pleural Cavities—Surround left and right lungs
  - Mediastinum—Between pleural cavities; Houses heart, great vessels, trachea (windpipe), and esophagus; Not within serous membrane
  - Pericardial Cavity—Within mediastinum; Within serous membrane that surrounds heart
- Abdominopelvic Cavity
  - Subdivided into superior Abdominal Cavity (diaphragm to bony pelvis) and inferior Pelvic Cavity (within bony pelvis)
  - Contains organs from digestive, lymphatic, urinary, and reproductive systems
  - Peritoneal Cavity—Abdominal subcavity found within serous membranes
- Abdominopelvic Cavity can be divided into segments by drawing imaginary lines through its surface
  - One system divides the cavity into four Quadrants
    - Right and left upper quadrants (R U Q and L U Q); Right and left lower quadrants (R L Q and L L Q)
  - A second system divides the cavity into nine Regions
    - Right and left hypochondriac regions, Right and left lumbar regions; Right and left iliac regions; Epigastric region; Umbilical region; Hypogastric region

Abdominal Pain

Abdominal pain is a common reason for people to seek health care, but the number of structures in the abdominopelvic cavity make diagnoses difficult
The four-quadrant system helps to narrow down potential diagnoses
For example, R L Q pain may be from the appendix, ovaries in female, the first part of the large intestine, or the last portion of the small intestine
Serous Membranes—Thin sheets of tissue that fold over to form continuous double-layered structures filled with Serous Fluid to lubricate organs in the cavity
- Visceral Layer—Contacts the organ
- Parietal Layer—Attaches to surrounding structures
Serous Membranes
- Pleural Membranes—Surround the lungs; Includes parietal and visceral pleura
- Pericardial Membranes—Surround the heart; Includes parietal and visceral pericardium
- Peritoneal Membranes—Surround some abdominal organs (Intraperitoneal); Includes parietal and visceral peritoneum
- Organs behind the parietal peritoneum are Retroperitoneal

Medical Imaging

Used to look inside patients without surgery; Different forms of radiation form images of internal structures often along specific planes
- X-Ray uses ionizing radiation; Chest image is shown (top)
- Computed Tomography Scan (C T) uses ionizing radiation; 3-D image is computer generated from data; Transverse section of abdominopelvic and peritoneal cavities is shown (bottom)
- Magnetic Resonance Imaging (M R I) involves the body being placed within a magnetic field; 3-D image is computer generated from data; Transverse section of the abdominopelvic cavity is shown

Core Principles in Anatomy and Physiology

Core Principles—Set of basic concepts of anatomy and physiology that are revisited repeatedly in the text; They are related to maintaining the body’s internal environment
- Feedback Loops
- Relationship of Structure and Function
- Gradients
- Cell-Cell Communication

Overall Theme: Physiological Processes Operate to Maintain the Body’s Homeostasis

Homeostasis—The condition in which the body develops and maintains a relatively stable internal environment
- Homeostatic Imbalances—Disturbances in homeostasis can lead to disease or death if uncorrected
- Regulated Variables—Variables in the internal environment, such as temperature, blood sugar, and many others, are controlled to stay close to a particular normal value
- Controlled Variables—Variables that are manipulated to maintain the regulated variables, such as the process that increases blood sugar from stored carbohydrates

Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis

Feedback Loops—A change in a regulated variable causes effects that feed back and in turn affect that same variable
- Made up of a series of events that lead to an output
- As the loops continue, this output then influences the events of the loops themselves
- Negative Feedback Loops—Oppose the initial change and reduce the output
- Positive Feedback Loops—Reinforce the initial change and increase the output
Negative Feedback Loops—Promote stability; Negating any stimulus that moves a variable away from homeostasis
Each variable has a Set Point that includes a Normal Range around that set point
- The range differs for individual variables
Steps of a Negative Feedback Loop
- Stimulus—Information that a regulated variable is outside the normal range
- Receptor or Sensor—Cellular structure that registers the stimulus
- Control Center—Stimulus is sent to the control center (brain or gland) by the nervous or endocrine systems
- Effector—The cells or organ that will react
- Responses—Effector causes the response that will return the variable to the normal range
Positive Feedback Loops—Less common than negative feedback loops; Increases the response to a stimulus; Reinforces the initial stimulus
- Will eventually shut off in response to an external stimulus or some outside event that is not part of the positive feedback loop
- Positive feedback loops are often found within a negative feedback loop to produce a quicker response

Common Misconceptions about Homeostasis

Misconception 1: Negative feedback is bad for the body; Positive feedback is good
- Under normal circumstances, both types of feedback loops promote homeostasis
Misconception 2: Maintaining homeostasis means the body’s internal environment is static or unchanging
- Maintenance of normal ranges does not mean the internal environment is unchanging; Changes are normal and are occurring constantly
Misconception 3: Regulatory mechanisms and feedback loops are either “on” or “off,” like a switch
- The internal environment is dynamic so feedback loops always exhibit some degree of activity
Misconception 4: Any physiological variable can be controlled
- Variables can only be controlled through feedback loops if receptors exist to detect changes in the set point
Childbirth begins when a woman goes into labor, which occurs by a positive feedback loop
- Baby’s head stretches the cervix (stimulus); Data from nerves in the cervix (receptors) are sent to the brain (control center); Uterus (effector) produces hormone oxytocin which stimulates uterine contractions (response); This continues and is amplified until the baby is born, which stops the feedback loop
- Pitocin is a synthetic version of oxytocin that is used when labor needs to be artificially started, or induced

Structure and Function are Related at All Levels of Organization

Principle of Complementarity of Structure and Function
- The form of a structure is such that it best suits its function; Applies to all levels of organization

Gradients Drive Many Physiological Processes

Gradients are present any time more of something exists in one area than another and the two areas are connected
- Gradients drive many of our physiological processes

Cell-Cell Communication is Required to Coordinate Body Functions

Cells communicate with each other to maintain homeostasis
- Electrical Signals are transmitted between neighboring cells
- Chemical Messengers released from cells may work on neighboring cells or move to other cells through body fluids