The Blood Flashcards
What are the functions and components of the blood
The blood has three general functions, Transport: of oxygen, carbon dioxide, nutrients, hormones, heat and waste products.
Regulates: homeostasis of all body fluids, pH, body temperature and water content of cells
Protects: against excessive loss by clotting (platelets) and against infections (white blood cells and antibodies)
Components of blood: 2 Main Components Whole blood and other fluids. Whole blood contains plasma which includes proteins (Albumins, globulins, fibrinogen), water and electrolytes, nutrients, gases, regulatory substances and waste products. and formed elements - Platelets, white blood cells (Neutrophils, lymphocytes, monocytes) and red blood cells
Describe the structure, functions, life cycle and production of Red blood cells (erythrocytes)
Do NOT have a nucleus or other organelle and so form biconcave discs (only live for 120 days)
Biconcave = easier to carry oxygen
Contains the proteins haemoglobin (Hb) which contains an iron ion which can bind 4 oxygen molecules
Oxygen attaches to Hb to form oxyhaemoglobin used to transport oxygen to all cells of the body
Carbon Dioxide (Waste) attached to Hb to carry23% of total carbon dioxide to the lungs for removal
Production: Negative feedback mechanism
Kidneys detect lowered oxygen concentration (Hypoxia) in the blood
Stimulates kidneys to release the hormone Erythropoietin (EPO)
Erythropoiesis (being in the red bone marrow)
Describe the structure, functions, life cycle and production of white blood cells (Leukocytes)
Do contains a nucleus organelle but no haemoglobin
Classified as being: Granular, contain besides that appear when cell are stained
Agranular: containing no granules
Functions: live for several months but mainly only a few days
Main function is to combat invading microorganisms
Describe the structure, functions and origin of platelets
Are used to clot the blood
The hormone thrombopoietin, directs the hemopoietic stem cells to differentiate into platelets
only survive nine days
Define haemostasis
Means to stop bleeding
Involves: 1. Vascular spasm
2. Platelet plug formation
3. Blood clotting (coagulation)
Define hypovolaemia
decreased volume of circulating blood in the body
Define solute
a minor component in a solutions
Define leukocyte
white blood cell
Define Erythrocyte
red blood cell
Define haemopoiesis (haematopoiesis)
The formation of new blood cells
Define Emigration (Diapedesis)
During in invasions many white blood cells are able to leave the bloodstream and collect at sites of invasion
