Blood Flashcards
What are components of blood?
Plasma, erythrocytes, leucocytes, phagocytes and platelets
What is plasma?
It makes up 55% of blood as its liquid yello medium that carries blood cells, platelets and dissolved substances
What are erythrocytes?
Red blood cells
What are leucocytes and phagocytes?
White blood cells
What are platelets?
Fragments of cells called megakaryocytes found in red bone marrow
What is the function of platelets?
Blood clotting
What are the dissolved substances in plasma?
Glucose, amino acids, mineral ions, hormones and large plasma proteins
What are examples of large plasma proteins?
Albumin and fibrinogen
What are examples of substances transported by blood?
Oxygen and carbon dioxide, digested food molecules, nitrogenous waste products chemical messengers antibodies and platelets
How is oxygen and carbon dioxide transported in the blood?
Oxygen to cells and carbon dioxide away from cells
How are digested food molecules transported in the blood?
From small intestine to cells
How are nitrogenous waste products transported in the blood?
From cells to excretory organs
Where are food molecules transported from?
Storage
How are platelets transported in the blood?
To damaged areas
How can dissolved substances move in and out of capillaries?
In the plasma, they can pass through gaps in capillary wall except large plasma proteins which have an osmotic effect
What is the water potential in capillaries as result of protein movement?
Low water potential so water moves into capillaries from fluid surrounding them
What is the osmotic pressure caused by proteins?
-3.3 kPa
Why is blood under pressure as it enters capillaries?
Pumping of heart
What is the result of capillary pressure?
Fluid is squeezed out of capillary as hydrostatic pressure is higher than osmotic pressure?
What is the result of fluid being squeezed out?
Dissolved substances in the tissue fluid diffuses into cell
What happens as blood moves back into venous system?
Hydrostatic pressure falls as fluid is pushed out, osmotic pressure remains so net pressure is negative
What is the result of blood moving back to venous system?
Water moves back into capillaries
What are interstitial spaces?
Spaces between cells where tissue fluid is
What is the lymphatic system?
A network of vessels similar to capillaries which runs paralegal to the circulatory system
