Communication & Homeostasis Flashcards
Glycogenesis
Converts glucose to glycogen in the cell for storage
Glycogenolysis
Conversion of glycogen to glucose
Gluconeogenesis
Production of glucose by converting from amino acids and fats
Hepatocytes
Liver cells that perform a range of metabolic functions
Stimulus
Change in the environment that causes a response
Response
Change in behaviour or physiology as a result if a change in the environment
Homeostasis
Maintenance of internal environment despite external changes
Negative feedback
A process that brings about a reversal of any change in conditions. Ensures homeostasis
Positive feedback
Process that increases any change detected by receptors
Ectotherm
An organism that relies on external sources of heat to regulate body temperature
Endotherm
An organism that can use internal sources of heat such as heat gained from metabolism to maintain body temperature
Polarised membrane
One that has a potential difference across it. This is the resting potential
Depolarisation
The loss of polarisation across the membrane as Na+ ions rush into the cell, making it less negative
Generator potential
Small depolarisation caused by Na+ ions entering the cell
Threshold potential
If depolarisation of the membrane reaches -50mV then an action potential is created
Action potential
A depolarisation of the membrane so that the inside is more positive that the outside (+40mV)
Resting potential
The difference of voltage across the neurone cell membrane while the neurone is at rest (-60mV)
Voltage gates channels
Channels that allow passed of particles or ions. They have gates which respond to changes in pd across the membrane