Introduction to Introduction to Human Anatomy & Human Anatomy & PhysiologyPhysiology

Chapter 1: Introduction to Human Chapter 1: Introduction to Human A&PA&P

Unit 1: Levels of OrganizationUnit 1: Levels of Organization

Anatomy & PhysiologyAnatomy & Physiology

The functional knowledge of anatomy and The functional knowledge of anatomy and physiology can be used to solve problems physiology can be used to solve problems concerning the healthy or diseased body.concerning the healthy or diseased body.

– AnatomyAnatomy: the branch of science that deals : the branch of science that deals with the structure (morphology) of body partswith the structure (morphology) of body parts

Their forms and how they are organizedTheir forms and how they are organized

– PhysiologyPhysiology: concerns that functions of body : concerns that functions of body partsparts

What they do and how they do itWhat they do and how they do it

Anatomy ContinuedAnatomy Continued

Coined by Coined by Aristotle about Aristotle about 2300 years ago.2300 years ago.

Derived from the Derived from the Greek words Greek words meaning to cut meaning to cut ((tomytomy) apart ) apart ((anaana))

Anatomy’s Sub-Anatomy’s Sub-DivisionDivision Gross AnatomyGross Anatomy: Study of structure and the interrelation of the : Study of structure and the interrelation of the

parts of the body by dissectionparts of the body by dissection

Microscopic Anatomy/HistologyMicroscopic Anatomy/Histology: Study of the tissues of the body : Study of the tissues of the body under the microscopeunder the microscope

Regional/Topographical AnatomyRegional/Topographical Anatomy: Study of the body, region by : Study of the body, region by regionregion

NeuroanatomyNeuroanatomy: Study of the structure and organization of the : Study of the structure and organization of the nervous systemnervous system

Surface AnatomySurface Anatomy: Study of projections of the arrangement of : Study of projections of the arrangement of internal structures on the surface of the bodyinternal structures on the surface of the body

Radiography AnatomyRadiography Anatomy: Study of structure and function of the : Study of structure and function of the body using radiographic techniquesbody using radiographic techniques

Embryology/Developmental AnatomyEmbryology/Developmental Anatomy: Study of growth and : Study of growth and development inside the uterusdevelopment inside the uterus

Sectional AnatomySectional Anatomy: Study of relationship of structure as visible in : Study of relationship of structure as visible in sections cut in different planessections cut in different planes

HistologyHistology

Testicle

Adrenal Gland

Surface AnatomySurface Anatomy

Sectional AnatomySectional Anatomy

Gross AnatomyGross Anatomy

What’s the Difference What’s the Difference b/n Anatomy & b/n Anatomy & PhysiologyPhysiology A&P are difficult to separate because A&P are difficult to separate because

the structures of body parts are so the structures of body parts are so closely associated with their function.closely associated with their function.

– A particular body part’s function A particular body part’s function depends on the way the part is depends on the way the part is constructedconstructed

ExampleExample: Organization of parts in the : Organization of parts in the human hand with its long, jointed fingers human hand with its long, jointed fingers makes it easy to grasp objects; hollow makes it easy to grasp objects; hollow chambers of the heart are adapted to pump chambers of the heart are adapted to pump blood through tubular blood vessels; Mouth? blood through tubular blood vessels; Mouth? Teeth?Teeth?

What’s the Difference What’s the Difference b/n Anatomy & b/n Anatomy & PhysiologyPhysiology Form begets function.Form begets function.

– This is another way of saying the This is another way of saying the same thing.same thing.

– A body part’s function (physiology) A body part’s function (physiology) is a direct result of its form is a direct result of its form (morphology/anatomy)(morphology/anatomy)

– This is a major theme in organismal This is a major theme in organismal studystudy

A&P: An Ongoing A&P: An Ongoing Ancient FieldAncient Field Researchers frequently discover new Researchers frequently discover new

information about physiology on the information about physiology on the molecular level.molecular level.

– Human genome (biochemical instructions Human genome (biochemical instructions that run the human body): discovering the that run the human body): discovering the activities of out 35,000 genes is revealing activities of out 35,000 genes is revealing new details of physiologynew details of physiology

Although unusual, new parts of human Although unusual, new parts of human anatomy are being discovered.anatomy are being discovered.

– A small piece of connective tissue between A small piece of connective tissue between the upper part of the spinal cord and a the upper part of the spinal cord and a muscle at the back of the head was muscle at the back of the head was recently discovered.recently discovered.

Characteristics of Life Characteristics of Life ReviewReview MovementMovement ResponsivenessResponsiveness GrowthGrowth ReproductionReproduction RespirationRespiration DigestionDigestion AbsorptionAbsorption CirculationCirculation Assimilation Assimilation ExcretionExcretion

How are the How are the Characteristics of Life Characteristics of Life Related to Metabolism?Related to Metabolism?

Metabolism - Metabolism - The acquisition of The acquisition of food and utilization of its energy, plus food and utilization of its energy, plus excretion, constitute metabolism.excretion, constitute metabolism.– All the chemical reactions that occur in All the chemical reactions that occur in

your cells constitute metabolism.your cells constitute metabolism.– Your Homework: Tell me how each of the Your Homework: Tell me how each of the

10 char. of life relate to metabolism!10 char. of life relate to metabolism!

Maintenance of LifeMaintenance of Life

The structures and functions of The structures and functions of almost all body parts help almost all body parts help maintain the life of the organism.maintain the life of the organism.

– Exception: an organism’s Exception: an organism’s reproductive structures which only reproductive structures which only ensure that its species will continue ensure that its species will continue into the futureinto the future

Requirements of Requirements of Organisms/LifeOrganisms/Life Water, Foods, Oxygen, Heat, and Water, Foods, Oxygen, Heat, and

Pressure.Pressure.

– Although organisms require all 5 of Although organisms require all 5 of these factors, they alone are not these factors, they alone are not enough to ensure survival.enough to ensure survival.

– Both the quantities and the qualities Both the quantities and the qualities of such factors are also very of such factors are also very importantimportant

Regulation for SurvivalRegulation for Survival

Body parts function only when the Body parts function only when the concentrations of water, nutrients, concentrations of water, nutrients, and oxygen and the conditions of and oxygen and the conditions of heat and ambient pressure remain heat and ambient pressure remain within certain narrow limits.within certain narrow limits.

– This condition of a stable internal This condition of a stable internal environment is called environment is called HomeostasisHomeostasis..

HomeostasisHomeostasis

This internal stability of the body This internal stability of the body is best described as a is best described as a dynamic dynamic equilibriumequilibrium or a or a balanced balanced changechange in which there is a in which there is a certain set point or an average certain set point or an average value for a given variable, and value for a given variable, and conditions fluctuate conditions fluctuate slightlyslightly around this point.around this point.

Homeostasis Homeostasis ContinuedContinued The functions of each body The functions of each body

system aid in maintaining system aid in maintaining homeostasis or internal stability.homeostasis or internal stability.

– Much of your physiology takes place Much of your physiology takes place in order to maintain homeostasis.in order to maintain homeostasis.

Homeostatic Homeostatic Mechanisms Maintain Mechanisms Maintain HomeostasisHomeostasis

The body maintains homeostasis through The body maintains homeostasis through a number of self-regulatory control a number of self-regulatory control systems or systems or Homeostatic MechanismsHomeostatic Mechanisms

Each homeostatic mechanism monitors Each homeostatic mechanism monitors an aspect of the internal environment an aspect of the internal environment and corrects any changes.and corrects any changes.

Components of Components of Homeostatic Homeostatic MechanismsMechanisms1.1. ReceptorsReceptors: which provide information : which provide information

about specific conditions (stimuli) in about specific conditions (stimuli) in the internal environmentthe internal environment

2.2. Set-PointSet-Point: tells what a particular value : tells what a particular value should be (i.e. body temperature)should be (i.e. body temperature)

3.3. EffectorsEffectors: respond to altered : respond to altered conditions in the internal environment, conditions in the internal environment, attempting to correct themattempting to correct them

How Does it Work?How Does it Work?

If the If the receptorsreceptors detect deviation from detect deviation from the the set pointset point, , effectorseffectors are activated are activated that can return conditions toward that can return conditions toward normal normal

As conditions return toward normal, As conditions return toward normal, the deviation form the set point the deviation form the set point progressively lessens, and the progressively lessens, and the effectors are gradually shut downeffectors are gradually shut down

Negative FeedbackNegative Feedback

Deviation from the Deviation from the set pointset point is is corrected corrected

– Moves in the opposite or negative Moves in the opposite or negative directiondirection

The correction reduces the action The correction reduces the action of the of the effectorseffectors

– This prevents a correction from This prevents a correction from going too fargoing too far

Biological ExamplesBiological Examples

Example 1Example 1: :

– Regulation of body temperatureRegulation of body temperature

Example 2Example 2: :

– Regulation of blood sugar levelsRegulation of blood sugar levels

Blood sugar Blood sugar homeostasishomeostasis The Pancreas acts as the The Pancreas acts as the receptorreceptor

– Detects blood sugar levelsDetects blood sugar levels– Initiates mechanisms that control levelsInitiates mechanisms that control levels

The The set pointset point is 90mg/100mL is 90mg/100mL– Low blood sugar is called Low blood sugar is called

hypoglycemiahypoglycemia– High blood sugar is called High blood sugar is called

hyperglycemiahyperglycemia

Blood sugar Blood sugar homeostasishomeostasis HyperglycemiaHyperglycemia

– Pancreas detects high blood glucosePancreas detects high blood glucose– Produces a hormone called Produces a hormone called insulininsulin, ,

which circulates in the bloodwhich circulates in the blood– High levels of High levels of insulininsulin make the make the liverliver

absorb glucose and store it as absorb glucose and store it as glycogenglycogen

– Hyperglycemia subsidesHyperglycemia subsides

Blood sugar Blood sugar homeostasishomeostasis HypoglycemiaHypoglycemia

– Pancreas Pancreas detects low blood glucosedetects low blood glucose– Produces a Produces a hormonehormone called called glucagonglucagon– High levels of High levels of glucagon glucagon make the liver make the liver

convert stored convert stored glycogenglycogen back into back into glucoseglucose & release it into the blood & release it into the blood

– Hypoglycemia is correctedHypoglycemia is corrected

Positive FeedbackPositive Feedback

Deviation from a set point is Deviation from a set point is amplifiedamplified– Exponential growthExponential growth– Rare in the human bodyRare in the human body– Ex: Blood clotting, childbirth, milk Ex: Blood clotting, childbirth, milk

productionproduction

Important Note!Important Note!

Homeostatic mechanisms maintain a Homeostatic mechanisms maintain a relatively constant internal relatively constant internal environment, yet physiological values environment, yet physiological values may vary slightly in a person from may vary slightly in a person from time to time or form one individual to time to time or form one individual to the next.the next.

– Both normal values for an individual and Both normal values for an individual and the the normal rangenormal range for the general for the general population are clinically important.population are clinically important.

Typical Homeostatic Typical Homeostatic ValuesValues Body Temperature: 98.6Body Temperature: 98.6ooF (37F (37ooC)C) Blood glucose: 90mg/100mLBlood glucose: 90mg/100mL Blood pressure: Blood pressure:

120mmHg/80mmHg120mmHg/80mmHg Heart rate: 70-80bpmHeart rate: 70-80bpm