Homeostasis and physiological organization Flashcards
physiology
how things work and how they function
homeostasis
the maintenance of a relatively stable internal environment
maintain set point
maintenance of a dynamic steadsy-state
set point
dictate the level of certain variables, goal is to maintain these to within a tight range
we can deviate from it, but we always will come back
explain the negative feedback loop
stimulus
sensor
signal to integrating center
signal to effector to initiate change
effector will fix problem
output will counteract input and return us to setpoint, offsetting initial stimulus
negative feedback loop for decrease in body temp
decrease temp
nerve endings
nerve signal about decreasing temperature
hypothalamus
nerve signal
skeletal and blood vessels
negative feedback system
feedback reduces the difference between the desired setpoint and the actual value
works to reduce the initial stimulus and regain homeostasis
positive feedback system
the feedback increases the difference between the normal setpoint and the actual value
if enhances the stimulus and moves the system away from homeostasis
explain the positive feedback loop for labour
baby drops, pressing on cervix
stretch receptors in the cervix
brain releases oxytocin
smooth muscles of the uterus
increased contractions
feedforward control
anticipatory response, body is pregaming
stimulus is not there but the body prepares in anticipation
increased breathing as soon as execise begins
salvation at the sight of food
biological hiearchy
atom
molecule
cell
tissue
organ
organ system
organism
lumen
interior of hollow organs
cytoplam
interior of cells
ICF
potassium abundant
2/3 of the total body water volume
ECF
sodium abundant
1/3 of the total body water volume
has interstitual fluid and blood plasma
interstitial fluid
lies between the circulatory system and cella
