Exchange of Material Flashcards
What needs to be transported in blood circulation?
Nutrients and fuels (from digestive system) respiratory gases intracellular waste protective agents (immune defences) regulator molecules (hormones)
Why is high pressure needed in the blood?
high pressure makes sure that the blood reaches every single cell in the body
Vertebrate circulatory system
closed system # heart chambers differ
Selective forces of the vertebrate circulatory system
body size
endothermy
effect of higher MR
How many chambers do fish, amphibian, reptile, bird and mammal hearts have?
Fish - 2
Amphibian -3
Reptiles - 3
Birds and mammals - 4
Fish vascular system
1 atrium and 1 ventricle (4 parts though)
blood enters in sinus venosus which is then pushed to the atrium
blood then pushed into ventricle
then into bulbus arteriosus
pump is sigmoid
Amphibian vascular system
blood returning from lungs to left atrium is oxygenated
blood returning from the skin is mixed with deoxygenated blood from the body
Reptile (non croc) vascular system
R-L shunt: direct blood to systemic system
L-R shunt: direct blood to pulmonary system
heart electrical properties
pacemaker creates AP cardiomycytes can contract without external stimulus specialized cells (pacemaker) set intrinsic heart rate
fish pacemaker
sinus venosus
vertebrate pacemaker
it is in the sinoatrial node (SA node)`
Electrocardiogram PQRST
P - atrial depolarization
Q-R-S complex - ventrical depolarization and atria polarization
T - ventricle polarization
relation between cardiac activity, body mass and oxygen needs
heart mass increases with body size in mammals
bigger heart = higher pressure
bigger animal = slower heart beat
Blood pressure
pressure in an artery depends on gravity as a result of the blood weigh from the heart to the organ in question
standing vs laying down blood pressure
standing: arterial pressure decrease in head, stays the same in abdomen and increases in legs
laying down: arterial pressure about same in head, abdomen and legs
giraffe
standing - high pressure in legs and low in head
bending = vasodilation of vessels in lower body
arteries in legs are thick and the tight skin and muscles allow for the blood to be pushed back up
neck has reinforced blood vessels to restrict bloodflow to head
Bradycardia, tachycardia, apnea
bradycardia: reduction of HR
tachycardia: increase of HR
apnea: interruption of external breathing
Blood components
plasma (55%)
leucocytes (<1%)
erythrocytes (45%)
plasma proteins
albumin (helps control osmotic pressure and diffusion of water)
globulin (includes antibodies and transport proteins)
fibrinogen (involved in clotting)
serum (blood plasma from which fibrinogen has been removed
Erythrocytes
smallest but most abundant is found in mammals
less abundant but bigger in poikilotherms
mammals do not have a nucleus in theirs
principle component is hemoglobin
hemoglobin
2 alpha and 2 beta chains with iron - O2 attaches to the iron and is transported
bad when it is saturated by CO2
oxyhemoglobin when O2 attached
Leucocytes
amount in blood is highly variable - depends on various factors
less than RBC
Platelets (thrombocytes)
smallest formed elements lack nucleus are fragments of megakaryocytes is mostly a mass of blood clots release serotonin to vasoconstrict and reduce blood flow to clot area survive 5-9 days
