physiology Flashcards
what is the cell membrane primarily composed of
phospholipids
phospholipid head and tail
head - hydrophobic
tail hydrophilic
what does cholesterol do to the membrane
stiffens/hardens it
what substances can cross the phospholipid bilayer easily
uncharged polar molecules e.g. O2, CO2, water and NH3
what is response for the fluidity of the membrane
lipid bilayer
name a ligand binding receptor
hormone receptor
what are adhesion molecules important in
regulating cell shape, growth and differentiation - allowing cell to adapt to its immediate surrounding
what is a glycocalyx
carbohydrate and lipid layer that surrounds some cells
what serves as self identity markers in cells
membrane carbohydrates
what are aquaporins
water channels
define tonicity
the effect a solution has on cell volume
what effect does overheating have
protein denaturation, nerve malfunction, convulsion
what effect does dec body temp have
slow down cellular reactions and metabolism
normal ear drum temp range
35.5 - 37.5
normal rectal temp range
36.7-37.5
when will you have your lowest body temperature
morning
what effect does menstruating have on your temp
higher during the 2nd half cycle
BMR
minimum amount of energy needed to sustain vital body functions
what effect do adrenaline and thyroxine etc have on BMR
inc it
what fat do children and hibernating animals have high level of
brown
what does brown adipose tissue contain
UCP
what does brown adipose tissue do
generate heat by short circuiting the mitochondrial battery - non shivering thermogenesis
which part of the hypothalamic centre is activated by cold
posterior
which part of the hypothalamic centre is activated by warmth
anterior
