health science directional terms

anterior

front

posterior

back

superior

toward head end

inferior

away from the head

medial

toward or at the midline of the body, inner side of

lateral

away from the midline of the body, outer side

intermediate

between a more medial and a more lateral structure

proximal

close to the origin of the body part - for extremeties

distal

farther from the orgin of a body part - for extremeties

superficial

toward the body surface

deep

away from the body surface, more internal

sagittal plane

left and right

median plane

equal left and right

frontal plane

anterior and posterior

transverse plane

superior and inferior

determination

process where stem cells become committed to developing into only one type of cells

differentiation

process by which committed cells acquire their specialized structures and functions

sensors

gather information about internal and external conditions and relay information to a control center

control center

receive information from sensors, compare it to set values, send messages through communication system

communication system

carry messages through nerves or blood to target organs, telling them how to respond to changes

targets

receive messages, change level of activity to help restore homeostasis

4 types of tissue

epithelial, connective, muscle, nervous

negative feedback

back to set point

positive feedback

moves away from set point

mechanisms of homeostasis

sensors, control center, communication system, targets

thermoregulation

maintaining a steady internal body temperature

type 1 diabetes

when the body’s immune system destroys pancreatic cells, not being able to produce enough insulin - regulates blood sugar levels by letting glucose enter cells

vitamin D production

skin - 1. UV light is changed into inactive form of vitamin D - enters blood and carried to liver 2. changes inactive vitamin D into another compound - carried to kidneys 2. converted into active vitamin D 4. carried to bones to make them stronger