circulatory system Flashcards
double circulatory system?
. mammals have closed, double circulatory system
- closed= blood remains within blood vessels
-double= blood passes through heart twice in each circuit. One circuit delivers blood to lungs and another delivers blood to rest of body
why do mammals have double circulatory system?
. to manage pressure of blood flow
. blood flows through lungs at lower pressure so prevents capillary damage in alveoli and reduces speed at which blood flows so more time for gas exchange
. oxygenated blood from lungs goes back through heart to be pumped out at higher pressure to rest of body which ensures blood reaches all respiring cells in body
key blood vessels?
. coronary arteries and following blood vessels attached to these organs:
- heart = vena cava, pulmonary vein and artery
- lungs= pulmonary artery and vein
- kidneys= renal artery and vein
. these major blood vessels are connected with circulatory system via arteries, arterioles, capillaries and veins
what is haemoglobin?
. quaternary structure protein that transports O2
affinity of haemoglobin for oxygen?
. the ability of haemoglobin to attract, or bind oxygen
saturation of haemoglobin with O2?
. when haemoglobin is holding max amount of O2 it can bind
loading/ association of haemoglobin?
. binding of O2 to haemoglobin
unloading/ dissociation of haemoglobin?
. oxygen detaches/ unbinds from haemoglobin
Oxyhaemoglobin dissociation curve?
. O2 loaded in regions w high partial pressure ( so high affinity) e.g alveoli and unloaded in regions of low partial pressure of O2 e.g respiring tissue ( so lower affinity= adv as O2 used for respiration)
why does haemoglobin have diff properties at diff pressures?
. cooperative binding-> cooperative nature of O2 binding to haemoglobin is due to haemoglobin changing shape when first O2 binds so easier for more O2 to bind
Bohr effect?
. high CO2 conc causes oxyhaemoglobin curve to shift to right. affinity for O2 decreases as acidic CO2 changes shape of haemoglobin slightly
affinity of haemoglobin in foetus?
. higher affinity so curve shifts to left and more saturated in O2. Adv because foetus can’t inhale and exhale, only O2 from mothers haemoglobin in blood supply from placenta so must have higher affinity for O2 to load O2
affinity of haemoglobin in llamas?
. live at high altitudes where there’s lower partial pressure of O2 so curve to left
affinity of haemoglobin in dove?
. decreased affinity for O2 so curve to right- adv because they have faster metabolism so need more O2 for respiration ( especially when flying for aerobic) to provide energy for contracting muscles so unloading O2 more readily
affinity of haemoglobin in earthworm?
. higher affinity so curve to left- live underground so lower partial pressure of O2 so need haemoglobin w higher affinity so can attract and load up w O2 they need
