Reading pages 2-8 Anatomy is – ◦ the study of the structure of body parts and their relationships to each other. ◦ Means “to cut apart” Physiology.

Reading pages 2-8

Anatomy is – ◦ the study of the structure of body parts and their

relationships to each other.◦ Means “to cut apart”

Physiology is – ◦ the study of the function of the body’s structure.

4 branches of anatomy –◦ Gross anatomy◦ Microscopic ◦ Developmental ◦ Specialized branches

Gross anatomy - ◦ Macroscopic ◦ Study of structures large enough to be seen with

the naked eye

3 categories of gross anatomy –◦ Regional –

study of all body structures in a body region

◦ Systemic – study of all structures in a body system body is studied system by system

◦ Surface – study of internal body structures as they relate to

the skin

Microscopic – ◦ Study of structures that are too small to see with

the naked eye◦ 2 categories of microscopic anatomy –

Cytology – Study of cells

Histology – Study of tissues

Developmental – ◦ Study of the change in body structures over the

course of a lifetime

◦ Embryology – Developmental changes that occur before and

after birth Helps to explain birth defects

Specialized branches of anatomy –◦ Pathology –

Study of structural changes associated with disease

◦ Radiology – Study of internal structures using specialized visual

techniques

◦ Molecular – Study of biological molecules

Essential tools for studying anatomy◦ Mastery of anatomical terminology

◦ Observation

◦ Manipulation

◦ Palpation (feeling organs with your hands)

◦ Auscultation (listening to organ sounds with a stethoscope)

Physiology – ◦ Studies the function or operation of organ

systems◦ Focuses/depends on

Cellular or molecular level Principles of physics

Complementarity of structure and function -◦ States that function is dependent on structure ◦ The form of a structure relates to its function

Chemical – ◦ Simplest level of organization

◦ Atoms – Tiny building blocks of matter Combine to form molecules MEET THE ELEMENTS

◦ Molecules – Combine specifically to form organelles Organelles (nucleus, mitochondria, endoplasmic

reticulum, etc.) are the basic unit of living cells

The cell is the smallest unit of life (cellular level), and varies widely in size and shape according to the cells function.

The tissue level is groups of cells having a common function. ◦ Epithelium, muscle, connective, and nervous

Organ level – ◦ Specific structure composed of two groups of tissues that

work together to perform a specific function Lungs – epithelial tissue and connective tissue

Organ systems – ◦ Groups of organs that work closely together to

accomplish a specific purpose◦ Cardiovascular system

Heart, lungs, blood vessels, and blood all work together to keep the body oxygenated

The organismal level is the total number of all structures working together to promote life.

Maintaining boundaries –◦ Allows the body to maintain separate internal and external

environments◦ Allows the body also maintain separate internal chemical

environments ◦ Cells are chemically separate from the body by the plasma

membrane◦ Internal environment kept separate by integumentary system

(skin)

Movement – ◦ Allows transport of molecules within the body –

Blood Food Urine

◦ Muscles = movement

Responsiveness –◦ Irritability ◦ Body’s ability to detect changes in the internal or

external environment and be able respond to the stimuli ◦ Reflex

Digestion –◦ Process of breaking down food into molecules that the

body can use ◦ Food is broken down into tiny molecules that can be

absorbed into the blood and used by cells

Metabolism –◦ All chemical reactions that occur in the body◦ Breaking down substances (catabolism)◦ Synthesizing more complex substances from simple

substances (anabolism)◦ ATP production ◦ Regulated by hormones, digestion, and oxygen

availability

Excretion –◦ Process of removing waste (non-useful substances)◦ Digestive system◦ Urinary system◦ Respiratory system

Reproduction –◦ Process by producing more cells or organisms◦ Meiosis and mitosis – one cell divides to produce

identical daughter cells

Growth –◦ The increase in size of body parts or the whole

organism ◦ Usually accomplished by increasing the number of

cells ◦ Individual cells can increase in size when not dividing

Organ systems work cooperatively to promote the well-being of the entire body

Check out pages 6 and 7

Get into a group of 3 and complete a foldable of the 12 organ systems. Must include:◦ Name of system◦ Organs involved◦ Brief description of what the system does (do your

best to put the book description into your own words)

Survival needs =◦ Factors that are required to maintain life◦ Include –

Nutrients Oxygen Water Body temperature Atmospheric pressure

Nutrients –◦ Chemical substances used for energy and the rebuilding

of cells

◦ Plant-derived food = Carbohydrates – bodies energy source Minerals & vitamins – required for chemical reactions &

oxygen transport

◦ Animal foods = Proteins – fuel for the body but less energy than carbs & help

for cell structure rebuilding Fats – cushion organs, energy reserve, and form insulating

layers

Oxygen –◦ Human cells need oxygen to perform reactions◦ Cells reactions are oxidative – requiring oxygen ◦ Transported by red blood cells◦ Air = 20% oxygen – transported to cells through the

respiratory system & by blood cells

Water –◦ Most abundant chemical substance in the body ◦ 60-80% of body is water◦ Chemical reactions need watery environment to perform◦ Provides base for body secretions and excretions◦ Acquired from food and liquids◦ Lost from evaporation through the lungs, skin &

excretions

Normal body temperature – ◦ Must be maintained for chemical reactions to take

place◦ Body temp must stay above 98ºF for chemical

reactions to occur at a normal rate◦ Body temp that gets too high can cause chemical

reactions to occur at such a rapid rate that the body can’t continue to function

◦ Most body heat is generated from the muscular system

Atmospheric pressure –◦ Force the air exerts on the surface of the body ◦ Breathing and gas exchange◦ High altitudes = lower atmospheric pressure =

lower cellular functions ◦ Must be present in appropriate amounts or

cellular functions can be slow or excessive pressure can cause cellular damage

Reading pages 8-12

Homeostasis is the ability of the body to maintain a relatively constant internal environment, regardless of environmental changes. ◦ A dynamic state of equilibrium or balance ◦ Internal conditions vary but always remain within

normal limits ◦ Communication throughout the body is essential

Accomplished by the nervous and endocrine systems

Homeostatic control mechanisms –◦ Components –

Variables – the regulated factor or event

Receptor – structure that monitors changes in the environment sensor that responds to changes or stimuli sends info to the control center

Control center – Structure that determines the set point (level or range) for a

variable Analyzes input Coordinates an appropriate response to the stimuli

Effector – Structure that carries out the response directed by the control

center

Most homeostatic control mechanisms are negative feedback mechanisms.

A negative feedback mechanism causes the variable to change in a way that opposes the initial change.◦ Cause the variable to change in the direction opposite to

that of the initial change – returns it to its “ideal” value ◦ Ex. Thermostat = sets temp & houses both the receptor

& control center – temp is set and when the temp drops the heating system turns on (effector) – when the temp is reached the thermostat is triggered off

Both the nervous system and the endocrine system are important to the maintenance of homeostasis.

The goal of negative feedback mechanisms is to prevent sudden, sever changes in the body. ◦ Examples:

Body temperature, withdrawal reflex, control of blood volume by ADH, heart rate, blood pressure, rate and depth of breathing, and blood levels of O2, CO2, and minerals

A positive feedback mechanism causes the variable to change in the same direction as the original change, resulting in a greater deviation from the set point ◦ Response enhances or exaggerates the original

stimulus so the activity (output) is accelerated ◦ Said to be positive because the changes occur in

the same direction as the initial disturbance ◦ Control infrequent events that don’t require

continuous adjustments

Positive feedback mechanisms typically activate events that are self-perpetuating ◦ Once initiated have a amplifying effect

Most positive feedback mechanisms are not related to the maintenance of homeostasis ◦ They can race out of control – so they are rarely

used to promote day to day life ◦ Examples:

Blood clotting Enhancement of labor contractions – oxytocin –

intensifies labor contractions

Homeostatic imbalances often results in disease

As we age our control systems become less efficient & stable

Positive feedback mechanisms can become out of control causing illness and diseases (some aspects of heart failure are due to out of control positive feedback mechanisms)

Reading pages 12-19

Anatomical position –◦ A position in which the body is erect

(standing), feet are slightly apart, palms face forward, and the thumbs point away from the body.

◦ In anatomical position, right and left refer to the right and left sides of the person being viewed.

◦ Anatomical position is always assumed

Directional terms –◦ Used to explain exactly where one body

part is in relation to another ◦ Very specific terminology

2 divisions of regional anatomy –◦ Axial –

Makes up the axis of the body Includes head, neck, and trunk

◦ Appendicular – The appendages of the body that attach to the axis

of the body Includes upper and lower limbs

◦ Regional terms designate specific areas within the axial and appendicular divisions. Designates specific areas within the body divisions

Body planes are flat surfaces that lie at right angles to each other

A section is named for the plane along which it is cut◦ Sagittal plane = sagittal section

Body planes =◦ Sagittal◦ Frontal◦ Transverse

Sagittal –◦ A vertical plane that separates the body into right

and left halves Median or midsagittal plane – Sagittal plane that lies

exactly along the body’s midline Parasagital –Sagittal plane that lies offset of the midline

Frontal –◦ A vertical plane that separates the body into

anterior and posterior parts ◦ Also called a coronal plane –

Divides the body across the crown of the head

Transverse –◦ A horizontal plane that runs from right to left◦ Divides the body into superior and inferior parts

Sections –◦ Cuts made along specific planes◦ Transverse –

Cross section Made along a transverse plane

◦ Oblique – Cuts made at angles between the horizontal and

vertical planes

Body cavities –◦ Spaces within the body that are closed to the

outside and contain the internal organs

◦ Dorsal body cavity – Space that houses the central nervous system Cranial –

Is within the skull & houses the brain Vertebral –

Spinal cavity Cavity within the vertebral column houses the spinal

cord

Ventral body cavity –◦ Anterior to & larger than the dorsal body cavity

◦ Thoracic – Superior division Surrounded by ribs and muscles

Pleural cavities – Houses lungs Mediastinum – Contains the esophagus & trachea Pericardial cavity - Encloses the heart

Ventral body cavities cont. –◦ Abdominopelvic –

Inferior division of the ventral body cavity Separated from thoracic by the diaphragm Abdominal cavity –

Contains the stomach, intestines, spleen, and liver Pelvic cavity –

Inferior part w/ in the bony pelvis Contains the bladder, reproductive organs, & the rectum

Serous membranes are also called serosae

Serous membrane contains…◦ Parietal –

Lines the cavity walls Named for specific cavities in which it is associated

◦ Visceral – Covers the outer surface of organs in the cavity Named for the specific organ in which it is associated

Serous membranes secrete & are separated by a thin layer of lubrication fluid = serous fluid ◦ allows organs to slide without friction along cavity

walls and between each organ

Figure 1.11a

Helps to divide into smaller areas for study

Oral and digestive – mouth and cavities of the digestive organs

Nasal –located within and posterior to the nose

Orbital – house the eyes

Middle ear – contains bones (ossicles) that transmit sound vibrations

Synovial – joint cavities

Figure 1.13