Human Anatomy and Physiology
Third Edition
Chapter 1
Introduction to Anatomy and Physiology
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1.2 Characteristics of Living Organisms (1 of 2)
Living Organisms share distinct properties
â˘Cellular CompositionâCells are the smallest units that carry out the functions of life
â˘MetabolismâLiving organisms carry out chemical processes collectively called metabolism
ââBuildingâ processes are known as Anabolism
ââBreaking downâ processes are known as Catabolism
â˘GrowthâAn increase in the size and/or number of cells
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1.2 Characteristics of Living Organisms (2 of 2)
Living Organisms share distinct properties (continued)
â˘ExcretionâElimination of potentially harmful waste products created by metabolic processes
â˘Responsiveness or IrritabilityâOrganisms sense and react to changes or stimuli in their environment
â˘MovementâOrganisms or individual cells of an organism move
â˘ReproductionâProduction of new cells during growth or repair or reproduction of new organisms
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1.2 Levels of Structural Organization and Body Systems (1 of 7)
The body is constructed of a series of progressively larger âbuilding blocksâ known as the Structural Levels of Organization
â˘Chemical LevelâThis is the smallest level; Chemicals range from tiny atoms to complex molecules
â˘Cellular LevelâGroups of many different types of molecules combine in specific ways to form cellular structures
â˘Tissue LevelâTwo or more cell types and material outside them, called extracellular matrix, combine to perform a common function
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1.2 Levels of Structural Organization and Body Systems (2 of 7)
Structural Levels of Organization (continued)
â˘Organ LevelâTwo or more tissue types combine to form an organ with a recognizable shape that performs a specialized task
â˘Organ System LevelâTwo or more organs that together carry out a broad function in the body
âThe human body has 11 organ systems
â˘Organism LevelâThe organ systems function together to make up the working human bodyâan organism
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1.2 Levels of Structural Organization and Body Systems (3 of 7)
Figure 1.5 Six structural levels of organization of the human body.
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1.2 Levels of Structural Organization and Body Systems (4 of 7)
Figure 1.6 The 11 organ systems of the human body
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1.2 Levels of Structural Organization and Body Systems (5 of 7)
Figure 1.6 The 11 organ systems of the human body
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1.2 Levels of Structural Organization and Body Systems (6 of 7)
Figure 1.6 The 11 organ systems of the human body
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1.2 Levels of Structural Organization and Body Systems (7 of 7)
Figure 1.6 The 11 organ systems of the human body
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1.2 Types of Anatomy and Physiology (1 of 2)
Study of Anatomy can be approached in several ways
â˘Systemic AnatomyâExamines individual organ systems
â˘Regional AnatomyâExamines the body in regions, such as the head and neck
â˘Surface AnatomyâExamines surface markings
â˘Gross AnatomyâExamines structures that can be seen with the unaided eye
â˘Microscopic AnatomyâExamines cells (Cytology) and tissues (Histology) with the use of a microscope
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1.2 Types of Anatomy and Physiology (2 of 2)
Study of Physiology includes numerous subfields
â˘Physiology subfields are classified by organ or organ systems, such as neurophysiology and cardiophysiology
â˘Physiologists can also study other structural levels of organization of the body such as chemical, cellular, and tissue levels
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1.3 Word Parts
â˘The language of science is built on Word Rootsâcore components of words with specific meanings
â˘Word roots are combined with Prefixes and Suffixes to yield scientific terms
â˘For example, combine the following:
âPrefix an- (means without)
âWord root encephala- (means brain)
âSuffix -ic (means condition of)
â˘âAnencephalicâ is the condition of lacking a part of the brain
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1.3 The Anatomical Position and Directional Terms (1 of 4)
Anatomical PositionâCommon frame of reference from which all body parts and regions are described regardless of position
âBody is standing upright
âFeet are shoulder width apart
âUpper limbs at the sides of trunk
âHead and palms facing forward
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1.3 The Anatomical Position and Directional Terms (2 of 4)
Directional TermsâDescribe the relative locations of body parts and markings to ensure accurate communication among scientists and healthcare professionals
â˘Anterior/PosteriorâAnterior refers to the front and posterior refers to the back; Can refer to body as a whole or to a body part
â˘Superior/InferiorâSuperior, 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
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1.3 The Anatomical Position and Directional Terms (3 of 4)
Directional Terms (continued)
â˘Proximal/DistalâProximal 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
â˘Medial/LateralâMedial 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
â˘Superficial/DeepâSuperficial refers to structures closer to the surface of the body and deep refers to structures farther below
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1.3 The Anatomical Position and Directional Terms (4 of 4)
Figure 1.7 Directional terms.
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1.3 Medical Errors
â˘Most medical errors occur when a patient is dispensed the wrong type or dose of medication
â˘Occasionally, they involve surgery and are known as âwrong siteâ or âwrong bodyâ procedures when the surgeon operates on the wrong part of the body or even the wrong patient
â˘Precise communication with appropriate use of anatomical terminology is critical to prevent medical errors
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1.3 Regional Terms (1 of 7)
Regional TermsâThe body can be divided into two broad regions: Axial (head, neck, and trunk); and Appendicular (upper and lower limbs or appendages)
â˘Each broad region can be divided into several smaller Regions
â˘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 âregionâ to give us the term brachial region
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1.3 Regional Terms (2 of 7)
Figure 1.8 Regions of the body.
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1.3 Regional Terms (3 of 7)
Figure 1.8 Regions of the body.
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1.3 Regional Terms (4 of 7)
Table 1.1 Regional Terms
Region of the Trunk
Pertaining To:
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
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1.3 Regional Terms (5 of 7)
Table 1.1 Regional Terms
Region of the Head
and Face
Pertaining To:
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
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1.3 Regional Terms (6 of 7)
Table 1.1 Regional Terms
Region of the Upper
Limb
Pertaining To:
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
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1.3 Regional Terms (7 of 7)
Table 1.1 Regional Terms
Region of the Lower
Limb
Pertaining To:
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
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1.3 Concept Boost: Putting Anatomical Terms Together (1 of 2)
1.Name the RegionâCervical region
2.Add Descriptive Directional Termsâ On anterior side, Lateral to midline; Begins inferior to mental region; Ends superior to thoracic region
3.Describe Depth of IncisionâDeep to skin and muscle; Superficial to underlying larynx
4.Put It All TogetherâIncision 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
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1.3 Concept Boost: Putting Anatomical Terms Together (2 of 2)
1.Name the RegionâLeft Crural
2.Add Descriptive Directional Termsâ On anterior and medial side; Proximal to tarsal region and distal to patellar region
3.Describe Depth of IncisionâDeep to skin and muscle but superficial to bone
4.Put It All TogetherâWound 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
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1.3 Concept Boost Mini Lecture: Putting Anatomical Terms Together
Use the link below to view A D A compliant video: Concept Boost Mini Lecture: Putting Anatomical Terms Together
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1.3 Planes of Section (1 of 4)
Planes of SectionâDivide a body or body part for examination
â˘Sagittal PlaneâDivides body into right and left sections
âMidsagittal Plane: Also called a Median Plane; Sections are equal
âParasagittal Plane: Sections are unequal
Figure 1.9a Sagittal plane.
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1.3 Planes of Section (2 of 4)
Planes of Section (continued)
â˘Frontal PlaneâAlso called a Coronal Plane; Divides body into anterior and posterior sections
Figure 1.9b Frontal plane.
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1.3 Planes of Section (3 of 4)
Planes of Section (continued)
â˘Transverse Planeâ Also called a Horizontal Plane or Cross Section; Divides body into superior and inferior sections or proximal and distal sections
â˘Oblique PlaneâUsed less frequently; Taken at an angle
Figure 1.9c Transverse planes.
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1.3 Planes of Section (4 of 4)
Study Boost: How to Learn Anatomical Terms
â˘Flashcards are popular because research shows that they work
âMake customized flashcards with Practice Anatomy Lab⢠Flashcards in the Study Area of MasteringÂŽ A&P
âMake handwritten flashcards
â˘Donât forget to âBring It Backâ by quizzing yourself and âMix It Upâ by randomizing the order
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1.4 The Posterior Body Cavity
CavityâAny space within the body; Protects internal organs and allows them to move
Posterior Body Cavityâ Located on posterior side of body
â˘Cranial CavityâWithin the skull; Includes the brain
â˘Spinal CavityâWithin the vertebral column; Includes the spinal cord
â˘Both cavities are filled with Cerebrospinal Fluid, which bathes both organs
Figure 1.10a Posterior body cavity, lateral view.
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1.4 The Anterior Body Cavity (1 of 8)
Anterior Body CavityâHas two main divisions separated by the muscular diaphragm
â˘Thoracic Cavity is superior to the diaphragm
â˘Abdominopelvic Cavity is inferior to the diaphragm
â˘Smaller cavities exist within the thoracic and abdominopelvic cavities formed by sheets of tissue termed Serous Membranes
Figure 1.10b Anterior body cavity, anterior view.
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1.4 The Anterior Body Cavity (2 of 8)
Anterior Body Cavity (continued)
â˘Thoracic Cavity
âPleural CavitiesâSurround left and right lungs
âMediastinumâBetween pleural cavities; Houses heart, great vessels, trachea (windpipe), and esophagus; Not within serous membrane
âPericardial CavityâWithin mediastinum; Within serous membrane that surrounds heart
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1.4 The Anterior Body Cavity (3 of 8)
Anterior Body Cavity (continued)
â˘Abdominopelvic CavityâSubdivided into superior Abdominal Cavity (diaphragm to bony pelvis) and inferior Pelvic Cavity (within bony pelvis)
â˘Contains organs from digestive, lymphatic, urinary, and reproductive systems
â˘Peritoneal CavityâAbdominal subcavity found within serous membranes
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1.4 The Anterior Body Cavity (4 of 8)
Abdominopelvic Cavity can be divided into segments by drawing imaginary lines through its surface
â˘One system divides the cavity into four Quadrants
âRight and left upper quadrants (R U Q and L U Q); Right and left lower quadrants (R L Q and L L Q)
â˘A second system divides the cavity into nine Regions
âRight and left hypochondriac regions, Right and left lumbar regions; Right and left iliac regions; Epigastric region; Umbilical region; Hypogastric region
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1.4 The Anterior Body Cavity (5 of 8)
Figure 1.11 The four quadrants and nine regions of the abdominopelvic cavity.
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1.4 Abdominal Pain
â˘Abdominal pain is a common reason for people to seek health care, but the number of structures in the abdominopelvic cavity make diagnoses difficult
â˘The four-quadrant system helps to narrow down potential diagnoses
â˘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
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1.4 The Anterior Body Cavity (6 of 8)
Serous MembranesâThin sheets of tissue that fold over to form continuous double-layered structures filled with Serous Fluid to lubricate organs in the cavity
âVisceral LayerâContacts the organ
âParietal LayerâAttaches to surrounding structures
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1.4 The Anterior Body Cavity (7 of 8)
Serous Membranes (continued)
â˘Pleural MembranesâSurround the lungs; Includes parietal and visceral pleura
â˘Pericardial MembranesâSurround the heart; Includes parietal and visceral pericardium
â˘Peritoneal MembranesâSurround some abdominal organs (Intraperitoneal); Includes parietal and visceral peritoneum
â˘Organs behind the parietal peritoneum are Retroperitoneal
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1.4 The Anterior Body Cavity (8 of 8)
Figure 1.13 The serous membranes of the anterior body cavities.
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1.4 Medical Imaging (1 of 2)
â˘Used to look inside patients without surgery; Different forms of radiation form images of internal structures often along specific planes
â˘X-Ray uses ionizing radiation; Chest image is shown (top)
â˘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)
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1.4 Medical Imaging (2 of 2)
â˘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
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1.5 Core Principles in Anatomy and Physiology
Core PrinciplesâSet of basic concepts of anatomy and physiology that are revisited repeatedly in the text; They are related to maintaining the bodyâs internal environment
â˘Feedback Loops
â˘Relationship of Structure and Function
â˘Gradients
â˘Cell-Cell Communication
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1.5 Overall Theme: Physiological Processes Operate to Maintain the Bodyâs Homeostasis
â˘HomeostasisâThe condition in which the body develops and maintains a relatively stable internal environment
âHomeostatic ImbalancesâDisturbances in homeostasis can lead to disease or death if uncorrected
âRegulated VariablesâVariables in the internal environment, such as temperature, blood sugar, and many others, are controlled to stay close to a particular normal value
âControlled VariablesâVariables that are manipulated to maintain the regulated variables, such as the process that increases blood sugar from stored carbohydrates
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (1 of 8)
Feedback LoopsâA change in a regulated variable causes effects that feed back and in turn affect that same variable
â˘Made up of a series of events that lead to an output
â˘As the loops continue, this output then influences the events of the loops themselves
â˘Negative Feedback LoopsâOppose the initial change and reduce the output
â˘Positive Feedback LoopsâReinforce the initial change and increase the output
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (2 of 8)
Negative Feedback LoopsâPromote stability; Negating any stimulus that moves a variable away from homeostasis
â˘Each variable has a Set Point that includes a Normal Range around that set point
â˘The range differs for individual variables
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (3 of 8)
Steps of a Negative Feedback Loop
1.StimulusâInformation that a regulated variable is outside the normal range
2.Receptor or SensorâCellular structure that registers the stimulus
3.Control CenterâStimulus is sent to the control center (brain or gland) by the nervous or endocrine systems
4.EffectorâThe cells or organ that will react
5.ResponsesâEffector causes the response that will return the variable to the normal range
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (4 of 8)
Figure 1.14 Control of room temperature by a negative feedback loop.
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (5 of 8)
Figure 1.15 Control of body temperature by a negative feedback loop.
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (6 of 8)
Study Boost: Keeping Track of the Bodyâs Feedback Loops
â˘Feedback loops occur in all body systems so there are many to remember
â˘As you learn new feedback loops, add them to the Feedback Loops Master List page at the front of the Active-Learning Workbook
â˘Use the list to quiz yourself âBring It Back,â review feedback loops from other chapters âSpace It Out,â and have a friend quiz you from the list in a random order âMix It Upâ
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (7 of 8)
Positive Feedback LoopsâLess common than negative feedback loops; Increases the response to a stimulus; Reinforces the initial stimulus
â˘Will eventually shut off in response to an external stimulus or some outside event that is not part of the positive feedback loop
â˘Positive feedback loops are often found within a negative feedback loop to produce a quicker response
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1.5 Feedback Loops Are a Key Mechanism Used to Maintain Homeostasis (8 of 8)
Figure 1.16 Control of blood clotting by a positive feedback loop.
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1.5 Common Misconceptions about Homeostasis (1 of 2)
â˘Misconception 1: Negative feedback is bad for the body; Positive feedback is good
âUnder normal circumstances, both types of feedback loops promote homeostasis
â˘Misconception 2: Maintaining homeostasis means the bodyâs internal environment is static or unchanging
âMaintenance of normal ranges does not mean the internal environment is unchanging; Changes are normal and are occurring constantly
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1.5 Common Misconceptions about Homeostasis (2 of 2)
â˘Misconception 3: Regulatory mechanisms and feedback loops are either âonâ or âoff,â like a switch
âThe internal environment is dynamic so feedback loops always exhibit some degree of activity
â˘Misconception 4: Any physiological variable can be controlled
âVariables can only be controlled through feedback loops if receptors exist to detect changes in the set point
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1.5 BioFlix: Homeostasis
Use the link below to view A D A compliant video: BioFlix: Homeostasis
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1.5 Childbirth, Pitocin, and Positive Feedback Loops
â˘Childbirth begins when a woman goes into labor, which occurs by a positive feedback loop
â˘Babyâs 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
â˘Pitocin is a synthetic version of oxytocin that is used when labor needs to be artificially started, or induced
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1.5 Structure and Function are Related at All Levels of Organization
Principle of Complementarity of Structure and Function
â˘The form of a structure is such that it best suits its function; Applies to all levels of organization
Figure 1.17 The relationship between structure and function.
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1.5 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
â˘Gradients drive many of our physiological processes
Figure 1.18 Examples of gradients.
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1.5 Cell-Cell Communication is Required to Coordinate Body Functions
â˘Cells communicate with each other to maintain homeostasis
â˘Electrical Signals are transmitted between neighboring cells
â˘Chemical Messengers released from cells may work on neighboring cells or move to other cells through body fluids
Figure 1.19 Communication between a nerve cell and a muscle cell.
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