Quiz 1 Flashcards
anatomy
“to cut apart”- how do things work- structure
physiology
“study of nature”- what does it do- function
look at anatomy on many levels
level of detail
organism of focus
area of interest
what is the anatomical reference position?
body and feet facing forwards
palms out, facing forward
inferior/superior
lower/higher
anterior/posterior
front/back
ventral/dorsal
front/back
medial/lateral
toward midline/away from midline
proximal/distal
toward nearest attachment point/away from nearest attachment point
coronal plane
front vs back
transverse plane
top vs bottom
sagittal plane
left vs right
homeostasis
tendency of an organism to maintain stable internal conditions despite change of outside condition
enables body to survive in diverse conditions
homeostatic control system
mechanisms that monitor internal environment and correct as needed
cellular level of homeostatic control
“local control”
isolated change
organ/whole organism level of homeostatic control
“reflex control”
long-distance signaling
Three major components for integration:
input
controller/integrating center
output
functions of integrator
maintains a set point within a normal range
look for error signals (changes) in input
responds to correct the error by controlling target effector (turns on/off)
Response loop
stimulus: change in internal environment
sensor: receptor
input: afferent neuron
controller: integrating center
output: hormone/neuron
target effector: muscle/gland
response: change corrected
set points can be modified- Example
fever
increases set point for core body temp
integrator= hypothalamus
Glucose homeostasis- two hormones
- insulin-brings glucose into liver cells, lowers glucose in blood
- glucagon- removes glucose from liver cells, raises glucose in blood
high blood sugar stimulates for…
insulin
low blood sugar stimulates for…
glucagon
what is the integrator of glucose homeostasis?
pancreas
what is the output of glucose homeostasis?
insulin/glucagon
feedback
some form of output is returned to the input in order to further regulate
open loop
no control of output
ex. fire
closed loop
control of output
ex. thermostat
negative feedback
output of system acts to oppose changes to the input of the system
- shuts off input
- self terminating
- serves homeostatic role
positive feedback
output of system acts to increase changes to the input of the system
- amplifies actions of the body
- not self-terminating (requires outside factors to shut off)
- not homeostatic
transcellular
membrane transport- goes through membran
paracellular
membrane transport- goes parallel to the membrane
passive transport
materials move down gradient, no energy required
active transport
materials move against gradient, requires energy
Types of passive transport
simple diffusion
osmosis- diffusion of water
facilitated diffusion- “easier diffusion” (channels and transporters)
bulk filtration- move large groups in same direction
Flux
the greater the concentration gradient the greater the flux
as temp increases flux increases
if diffusion coefficient is big, flux is big
friction goes up, flux goes down
Types of transporters
channels
carriers
pumps
channels
typically for ions
passive, classic facilitated diffusion
carriers
“doorman” mechanism
could be passive or active
pumps
move solute against the gradient
primary active transport
uniport
1 thing in 1 direction
symport
2 things in 1 direction
antiport
2 things in different directions
