communication and signalling Flashcards
action potential
a wave of electrical excitation along a neurons plasma membrane
cones
photoreceptor cells responsable for colour vision only functioning in bright light
cyclic GMP
a second messenger for visual transduction, its present in high concentrations of photoreceptor cells
depolarisation
an electrical state in an excitable cell whereby the inside of the cell is made less negative relative to the outside than it is at the resting membrane potential
diabetes mellitus
an inability to regulate blood glucose levels
type 1- failure to produce insulin
type 2- loss of function of insulin receptors on cell surface
extracellular signalling molecule
cues designed to transmit specific information to target cells
GLUT4 glucose transporter protiens
insuilin-regulated glucose transporter
insulin triggers the movement to GLUT4 transporters to the membrane surface increasing uptake of glucose to be converted to glycogen
G-proteins
act as molecular switches inside cells which are involved in transmitting signals from a variety of stimuli outside a cell to its inside
hormone response elements
a short sequence of DNA within the promoter of a gene that is able to bind to a specific hormone-receptor complex and therefore regulate transcription
hormnoe receptor complex
formed when steroid hormones bind to specific receptors in the cytosol of the nucleus they bind to specific sites on DNA and affect gene transfer
hydrophillic
water loving
hydrophillic signalling molecule
signalling molecules that aren’t able to pass through the membrane the signal is transduced across the membrane by receptor molecules on the cell surface
hydrophobic
water fearing
hydrophobic signalling molecules
signalling molecules that can pass though the membrane so the receptor molecules can be inside the molecule
ion concentration gradient
gradients created by ion pump enzymes that transport ionic solutes across the membrane , energy needed
