chapter 1 notes

I.        The Human Body: An Orientation

1)   An overview of Anatomy and Physiology

a)    Introduction

b)   Definitions

i)     Anatomy-Study of the structure and shape of the body and its part.

ii)    Physiology-Study of how the body and its parts work or function.

c)    Topics of Anatomy

i)     Gross-large structures, easily observed, studied through dissection.

ii)    Microscopic anatomy- very small structures, can only viewed with a microscope.

(1)  Cytology- study of cells.

(2) Histology- study of tissues.

d)   Topics of Physiology

i)     Renal-Kidney

ii)    Cardiovascular-Heart and blood vessels function.

iii)  Neural-Nervous system functions.

iv)   Other organ system physiology

e)    Complementarity of structure and function

2)   Levels of structural organization

a)    Levels of structural hierarchy (See Fig. 1.1)

i)     Chemical level-Atoms combine to form molecules

(1)  Atoms-Atoms make up molecules.

(2) Molecules-Molecules make up cells.

ii)    Cellular level-Cells are made up of levels.

iii)  Tissue level-tissues consist of similar types of cells.

iv)   Organ level-Organs are made up of different types of tissues.

v)    Organ system level- Organ systems consist of different organs that work together closely.

vi)   Organismal level- Human organisms are made up of many organ systems.

vii) Close relationship between structure(anatomy) & function(physiology)

b)   Summary of the body’s organ systems (See Fig. 1.2)

i)     Integumentary System-Forms the external body covering, protects deeper tissue from injury, helps regulate body temperature, location of cutaneous nerve receptors.

ii)    Skeletal System-Protects and supports body organs, provides muscle attachment for movement, site of blood cells formation, stores minerals.

iii)  Muscular System-Produces movement, maintains posture, produces heat.

iv)   Nervous System- Fast-acting control system, responds to internal and external change, activates muscles and glands.

v)    Endocrine System-Secretes regulatory hormones: growth, reproduction, metabolism.(slow acting system)

vi)   Cardiovascular System-Transports materials in the body by blood pumped by the heart: oxygen(in),carbon dioxide(out), nutrients, wastes.

vii) Lymphatic System / Immune System-Returns fluids to blood vessels, cleanses the blood, involved in your immunity.

viii)        Respiratory System- Keeps blood supplied with oxygen, removes carbon dioxide.

ix)  Digestive System- Breaks down food, allows for nutrient absorption into blood, eliminates indigestible material.

x)   Urinary System-Eliminates nitrogenous wastes, maintains acid-base balance, regulates water and electrolytes,

xi)  Reproductive System- Produces offspring.

3)  Necessary Life Functions

            a) maintain boundaries- Gradients=differences.

            b) movement-Locomotion- organism moves, Movement of substances- within      or outside.

            c) responsiveness-Ability to sense changes and react.

            d) digestion-Break-down and absorption of nutrients.

            e) metabolism-Chemical reactions within the body= produces energy from food, makes body structures.

            f) excretion-Eliminates waste from metabolic reactions.

            g) reproduction-Produces future generation.

            h) growth- Increases cell size and number of cells.

3)   Homeostasis(our body’s happy place)

a)    Definition-Maintenance of a stable internal environment, a dynamic state of equilibrium, homeostasis is necessary for normal body functioning and to sustain life. Homeostasis imbalance= a disturbance in homeostasis resulting in disease.

b)   Homeostatic control mechanisms (See Fig. 1.4)

i)     Elements of a control system

(1)  Receptor(sensor)

(2) Control center

(3) Effector

ii)    Negative feedback mechanism (See Fig. 1.5)-Included most homeostatic control mechanisms, shuts off the original stimulus, or reduces its intensity, works like a household thermostat.

(1)  Opposite directional change

(2) Effector decreases original stimulus

iii)  Positive feedback mechanism (See Fig. 1.6)- Increases the original stimulus to push the variable farther, in the body this only occurs in blood clotting and during the birth of a baby.

(1)   Same directional change

(2) Effector enhances original stimulus

4)   The language of Anatomy-Special terminology is used to prevent misunderstanding parts.(position, direction, regions, and structures)

a)    Anatomical position

i)     Human body erect

ii)    Arms at sides

iii)  Palms forward

iv)   Feet together

b)   Directional terms (See Table 1.1)

i)     Definition:  Directional terms allow us to explain where one body structure is in relation to another.

ii)    Superior-toward head / inferior-far from head

iii)  Anterior-front (ventral) / posterior-back (dorsal)

iv)   Proximal-close to origin of body part, point of attachment / distal-distant from origin and point of attachment

v)    Lateral-closer to outer / intermediate-in the middle/medial-closer to middle

vi)   Superficial (external)-toward the body surface / deep (internal)-farther from surface, inside

c)    Regional terms (See Fig. 1.7)

i)     Definition: Regional terms are used to designate specific areas within the major body divisions

(1)  Axial part = head, neck and trunk

(2) Appendicular part = appendages or limbs

ii)    Anterio-Front

·         Nasal (nose)

·        Oral (mouth)

·        Cervical (neck)

·        Axillary (armpit)

·        Frontal (forehead)

·        Orbital (eye)

·        Buccal (cheek)

·        Sternal (breastbone)

·        Thoracic (chest)

·        Mammary (breast)

·        Abdominal (abdomen)

·        Brachial (arm)

·        Umbilical (navel)

·        Pelvic (pelvis)

·        Femoral (thigh)

·        Carpal (wrist)

·        Digital (fingers)

·        Coxal (hip)

·        Pubic (genital region)

·        Patellar (anterior knee)

·        Pedal (foot)

iii)  Posterior body landmarks-Back

·        Cephalic (head)

·        Otic (ear)

·        Sacral (between hips)

·        Occipital (base of the skull)

·        Vertebral (spinal column)

·        Scapular (shoulder blade)

·        Dorsal (back)

·        Gluteal (buttock)

·        Calcaneal (heel)

·        Plantar (sole)

·        Acromial (point of shoulder)

·        Popliteal (back of the knee)

d)   Body planes (See Fig. 1.8)

i)     Sagittal plane- Divides the body(or organ) into left and right parts.

(1)  Midsagittal = median plane- Section divides the body(or organ) into equal left and right parts.

(2) Parasagittal

ii)    Transverse plane = horizontal plane-Or cross, section divides the body(or organ) into superior and inferior parts.

iii)  Oblique- Doesn’t fit any plane

(1)  Side abs, go on an angle

iv)   Frontal plane-Section divides the body(or organ) into anterior and posterior parts.

e)    Body cavities (See Fig. 1.9)

i)     Dorsal body cavity

(1)  Cranial cavity- Houses the brain.

(2) Vertebral(spinal) cavity-Houses the spin

ii)    Ventral body cavity

(1)  Thoracic cavity-Houses the heart, lungs, and others.

(a)  Pleural cavities

(b) Pericardial cavity

(2) Abdominopelvic cavity-Houses digestive system and most urinary system organs.

(a)  Abdominal cavity

(b) Pelvic cavity

f)    Membranes in the ventral body cavity (See Fig. 1.10)

i)     Serous membrane = Serosa

(1)  Parietal serosa

(2) Visceral serosa

ii)     Serous fluid

(1)  Location

(2) Functions

iii)  Examples of serous membranes

(1)  Pericardium

(2) Pleura

(3) Peritoneum

g)    Quadrants