TRANSPORT IN ANIMALS - Proteins, albumin (osmotic pressure)
- Fibrinogen (blood clotting)
Circulatory systems - WBC (transport + immune system)
Open system - Platelets (red bone marrow) stick exposed collagen,
- Haemolymph = food, nitrogenous waste, WBC change shape + release clotting factors (thrombin to
- Direct contact with cells (not gas exchange) fibrin, traps RBC and strengthen platelets)
- Open ended vessels, body cavity = haemocoel, ↓P
- Cannot be varied to match demand + ↓ gradient Tissue fluid
- Ultrafiltration = HP>OP
Closed system - Dissolved substances pass through fenestrations in
- In vessels so no direct contact (through walls) capillary walls (not large proteins)
- Under pressure, adjust lumen size - Albumin has osmotic effect (↓), water moves into
capillaries (oncotic pressure =-3.3kpa)
Single circulatory - ↑ hydrostatic pressure near arterioles so fluid
- Blood pumped through heart 1x for each circuit squeezed out of capillaries = tissue fluid
- 2 capillary network, blood returns slowly as ↓P - Same composition as plasma (no RBC + proteins)
- Fish (Counter current, not maintain own temp) - At venule end, ↓ hydrostatic pressure, oncotic
pressure stronger so water moves back in (90%)
Double circulatory
- Mammals that maintain own body temp Lymph
- ↑ metabolic rate, ↓ SA:V - 10% tissue fluid to blind ended
- Double – pass through 2x for each circuit tubes = lymph
- Pulmonary (to lungs), systematic (to body) - Similar to plasma, ↓O2 + fewer
- One capillary network + under ↑P nutrients, fatty acids from villi
(small intestine)
Blood vessels - Contractions, valves, back to
Elastic fibres (p), smooth muscle (lumen), collagen (struc) blood = subclavian veins
- Lymph nodes = lymphocytes
Arteries + arterioles build, produce antibodies,
- Oxygenated blood away from heart (pulmon/umbilic) intercept bacteria
- ↑ pressure, ↑ blood vol (limited by collagen)
- Elastic fibres = withstand force + even surges Heart
- Endothelium lining is smooth = easy flow
- Arterioles link arteries + capillaries, smooth muscle,
less elastin, can constrict, vasodilation/constriction
Capillaries
- Link arterioles and venules
- Small lumen, RBC single file (8 m)
- Single endothelial cell thick
- ↑ SA – substances diffuse through walls into fluid
- Total CSA > supplying arteriole = ↓ blood rate (slows)
Veins + venules
- Deoxygenated blood into heart (pulmon/umbilic)
- No pulse, ↓ blood pressure, valves prevent backflow
- Lots of collagen, little elastin, wide lumen
- Varicose veins (valves not work = backflow)
- Bigger veins in active muscles, contractions squeeze
- Breathing movements act as pump - LORD: left = oxygenated, right = deoxygenated
- Cardiac muscle = no fatigue
Transportation - Surrounded by inelastic pericardial membrane
Blood preventing the heart from over distending
- O2 + CO2, Nitrogenous waste, Hormones, Platelets, - Septum prevents mixing
Cells for immune response - Left side thicker, longer distance to pump, stronger
- Plasma (55% blood, mostly water) contraction, overcome aorta resistance
- Dissolves glucose, aa, hormones, mineral ions