Intro Lecture Flashcards
Know homeostasis, body planes + axis
Homeostasis
What is it? What does it control?
Is active process of by which the body keeps many parameters in a narrow range
Ex: body temp (outside the body vs inside), blood sugar levels, concentrations of salt, O2 + CO2
Is not equilibrium
living organism + equilirium = death
Negative feedback
Definition + process
Occurs when the body detects a change in parameter, makes changes in the opposite direction thus maintaining homeostasis.
1. Stimulus produces a change in variable
2. Receptor detects change > sends signal to control center
3. Input (to control center) > compares levels
4. Output changes that need to be made
5. Effector - takes action that returns variable to the desired level
Control center
Is how the body does negative feedback.
Hypothalimus region of the brain.
Variable
Refers to what the body wants to maintain homeostasis of.
Receptor
purpose
Responsible for detecting the level of a variable.
Positive Feedback
Occurs when the body detects a change in variable + makes bigger changes in the same direction.
This leads to fast changes but not homeostasis.
Ex: Blood clotting + childbirth
Body Axis
Superior
up towards the head
Body Axis
Inferior
down towards the heels
Body Axis
Midline
Imaginary line separating left and right sides of the body.
Cuts through the nose + belly button
Body Axis
Medial
towards the midline
Body Axis
Lateral
away from the midline
Body Axis
Anterior
Ventral / torwards the front
Body Axis
Posterior
Dorsal / towards the back
Body Axis
Proximal
Applies to limbs only
towards the body
Anterior / Posterior for arm - assume hand is facing up
Body Axis
Distal
Applies to limbs only
away from the body
Anterior / Posterior for arm - assume hand is facing up
