blood, tissue fluid and lymph

• hydrostatic pressure?

  pressure exerted by liquid
• oncotic pressure?

  tendency of water to move into blood via osmosis
• what colour is plasma?

  yellow
• composition of blood?

  Red blood cells, white blood cells, platelets, and plasma.
• what properties of water affect blood?

  good transport medium, cohesion, high specific heat capacity meaning temperature is stable - maintaining optimum temperature stopping haemoglobin from denaturing
• is haemoglobin an enzyme?

  no
• features of erythrocytes?

  flattened biconcave disc giving large SA:V ratio for efficient gas exchange, no nucleus or organelles to maximise space for haemoglobin, diameter larger than capillary lumen to slow blood flow
• how is tissue fluid formed?

  blood plasma forced out of capillaries
• what does gas exchange occur between?

  tissue fluid and body cells
• RBC are transported in the plasma
• what component of blood is involved in blood clotting?

  Platelets
• blood helps maintain body temperature and minimises pH changes
• large plasma proteins cannot leave capillaries giving it a low water potential compared to the surrounding fluid, water has a tendency to move into the blood
• C?

  C

  
• c?

  c

  
• as blood enters the capillaries from the arterioles the smaller diameter results in high hydrostatic pressure
• at the arterial end of the capillaries the hydrostatic pressure is higher than the oncotic pressure so the net movement of liquid is out of the blood in capillaries
• low water potential means high oncotic pressure
• towards the venule end of the capillaries the hydrostatic pressure is low due to the loss of liquid, the water potential is low and liquid moves into the capillary by osmosis
• does all tissue fluid get reabsorbed?

  no
• what is the remaining tissue fluid after reabsorption known as?

  Lymph
• does lymph return to the blood?

  yes
• remaining tissue fluid is absorbed into the lymphatic system and is returned to the blood, liquid in the lymphatic system is called lymph
• c?

  c

  
• lymph contains more lipids than tissue fluid