A & P Chapter 1 The Human Body: An Orientation

anatomy

study of the shape and structure of the body

physiology

study of the function of the body's parts

levels of structural organization (6)

atomic, cellular, tissue, organ, organ system, organism

atoms

building blocks of matter, combine to form molecules

cells

smallest units of all living things

tissues

groups of similar cells that have a common function

organ

two or more tissue types that perform a specific function for the body

organ system

group of organs the work together to accomplish a common purpose

organism

sum total of all structural levels working together

human organ systems (11)

integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive

integumentary system

external covering of the body - waterproofs and protects; secretes salts and urea (sweat); helps regulate body temperature

skeletal system

bones, cartilages, ligaments, joints - supports body; creates framework for skeletal muscle; protects organs; houses blood formation (hematopoiesis)

muscular system

allows manipulation of environment, locomotion, facial expression; maintains posture; produces heat

nervous system

fast-acting control system of the body; responds to internal and external changes by activating appropriate muscles and glands

endocrine system

glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use by body cells

cardiovascular system

blood vessels transport blood, which carries oxygen, carbon dioxide, nutrients, wastes, etc.; heart pumps blood

lymphatic system

picks up fluid leaked from blood vessels and returns it to blood; disposes of debris in the lymphatic stream; houses white blood cells involved in immunity

respiratory system

keeps blood constantly supplied with oxygen and removes carbon dioxide; gaseous exchanges occur through walls of the air sacs

digestive system

breaks foo down into absorbable units that enter the blood for distribution to body cells; indigestible foodstuffs are eliminated as feces

urinary system

eliminates nitrogen-containing wastes from the body; regulates water, electrolyte, and acid-base balance of the blood

reproductive system

for production of offspring - In the male, testes produce sperm and male sex hormone; ducts and glands aid in delivery of viable sperm to the female reproductive tract.

In the female, ovaries produce eggs and female sex hormones; remaining structures serve as sites for fertilization and development of fetus; mammary glands of female breast produce milk to nourish newborn.

necessary life functions (8)

maintaining boundaries; movement; responsiveness; digestion; metabolism; excretion; reproduction; growth

survival needs (5)

nutrients; oxygen; water; normal body temperature; atmospheric pressure

homeostasis

body's ability to maintain relatively stable internal conditions even though the outside world is continuously changing

receptor

sensor that monitors and responds to changes (stimuli) in the environment

afferent pathway

flow from receptor to control center

control center

determines level (set point) at which a variable is to be maintained, analyzes info it receives, then determines appropriate response or course of action

effector

provides means for control center's response to stimulus

efferent pathway

flow from control center to effector

negative feedback mechanism

net effect of the response to the stimulus is to shut off the original stimulus or reduce its intensity (most homeostatic control mechanisms are neg.)

positive feedback mechanism

increase the original disturbance (stimulus) and push the variable farther from its original value - control infrequent, explosive events like blood clotting and childbirth

homeostatic imbalance

disturbance of homestasis

anatomical position

standard position for study; body erect, face-front, feet parallel, arms down, palms forward

superior (cranial, cephalad)

toward the head end or upper part of a structure or the body; above

inferior (caudal)

away from the head end or toward the lower part of a structure or the body; below

ventral (anterior)

toward or at the front of the body;in front of

dorsal (posterior)

toward or at the backside of the body; behind

medial

toward or at the midline of the body; on the inner side of

lateral

away from the midline of the body; on the outer side of

intermediate

between a more medial and a more lateral structure

proximal

close the origin of the body part or the point of attachment of a limb to the body trunk

distal

farther from the origin of a body part or the point of attachment of a limb to the body trunk

superficial (external)

toward or at the body surface

deep (internal)

away from the body surface; more internal

frontal

forehead

orbital

eye

nasal

nose

buccal

cheek

oral

mouth

mental

chin

cephalic

head

cervical

neck

thoracic

chest

sternal

breastbone

axillary

armpit

abdominal

anterior trunk inferior to ribs

umbilical

navel

inguinal (groin)

where thighs meet trunk

pubic

genital

occipital

posterior of head

dorsal

back

scapular

shoulder blade

vertebral

spinal column

lumbar

inferior, medial dorsal region

sacral

posterior, between hips

gluteal

buttock

acromial

point of shoulder

deltoid

over deltoid muscle

brachial

arm

antecubital

anterior elbow

olecranal

posterior elbow

antebrachial

forearm

carpal

wrist

manus

hand

digital

finger or toe

coxal

hip

femoral

thigh

patellar

anterior knee

politeal

posterior knee

crural

anterior leg

sural

posterior leg/calf

fibular

lateral leg

pedal

foot

tarsal

ankle

calcaneal

heel

plantar

sole of foot

metatarsal

superior surface of foot

section

cut

plane

imaginary lines that lie at right angles to each other in the body

sagittal section

cut along a longitudinal plane that divides body into right and left parts

midsagittal/median section

cut along center of longitudinal plane

frontal (coronal) section

cut along a longitudinal plane that divides body into anterior and posterior parts

transverse (cross) section

cut along a horizontal plane that divides body into superior and inferior parts

dorsal body cavity

composed of cranial and spinal cavities

cranial cavity

space inside the bony skull

spinal cavity

space containing spinal cord and vertebrae

ventral body cavity

contains chest and abdomen

thoracic cavity

lungs, heart, etc; somewhat protected by rib cage

diaphragm

dome-shaped muscle separates thoracic and abdominopelvic cavities