Homeostasis Flashcards
(23 cards)
1
Q
- Physiological variable
- manipulated to maintain the regulated variable with normal values
A
Control variable
2
Q
- Physiological variable
- sensors are present in the homeostatic circuit
- maintained at stable level by negative feedback system
A
Regulated variables
3
Q
- A device
- measures the magnitude of a physiological variable
- generates an output signal that is proportional to the magnitude of a stimulus
A
Sensor
4
Q
Determines difference between the set point value and actual value of regulated variable
A
Error detector
5
Q
- Receives info from the error detector
- sends output signals to increase or decrease the effector activity
A
Controller signal
6
Q
- A component of the homeostatic circuit
- activated by controller to change value of regulated variable
A
Effector
7
Q
- Movement of particles from a place of high concentration to low,
- down conc gradient
A
Simple diffusion
8
Q
- Passive transport,
- exclusively the movement of water across cell membranes
- via channel proteins
A
Osmosis
9
Q
- Water and solutes being driven through the cell membrane by hydrostatic pressure
- passive process
A
Filtration
10
Q
- Carrier-mediated transport of a solute through cell membrane
- down it’s concentration gradient
- passive
A
Facilitated diffusion
11
Q
- Carrier-mediated transport of solutes through the cell membrane
- up its concentration gradient
- using energy provided by ATP
A
Active transport
12
Q
- through the cell membrane in bubble-like vesicles of membrane
- Movement of large particles, droplets of fluid or numerous molecules at once
A
Vesicular transport
13
Q
- a chemical messenger diffuses a short distance through the EFC
- binds to receptor at same cell
A
Autocrine signalling
14
Q
- a chemical messenger diffuses a short distance through the EFC
- binds to a receptor on nearby cell
A
Paracrine signalling
15
Q
- a hormone is released into the bloodstream
- binds to a specific target cell receptor
A
endocrine signalling
16
Q
- rapid transmission of active potentials,
- often over long distances
- the release of a neurotransmitter at a synapse
A
nervous signalling
17
Q
- release of a hormone from a nerve cell
- the transport of the hormone by the blood to a distant cell
A
neuroendocrine signalling
18
Q
- allow specific particles to cross the membrane in response to an existing conc grad
A
ion channels
19
Q
- open in response to a specific chemical messages that bond to the extracellular region of the channel
- also known as ligand-gated channels
A
chemically-gated channels
20
Q
open in response to changes in membrane potential
A
voltage-gated channels
21
Q
open in response to physical distortion of membrane surface
A
mechanically-gated channels
22
Q
- open and close at random
- no actual event that opens the channel
- have an intrinsic rate of switching between open and closed states
A
leak channels
23
Q
- a distribution across the cell membrane
- measured in millivolts.
- the standard is to compare the inside of the cell relative to the outside when the outside is 0
A
a potential
