Blood Physiology Flashcards
Functions of blood
- Transport of:
- gases, nutrients, waste products
- processed molecules
- regulatory molecules
- regulation or pH and osmosis
- maintenance of body temperature
- proctor took against foreign substances
- clot formation
What is the composition of blood?
Plasma - 55%
** made up of 7% proteins, 91% water, 2% other solutes**
Buffy coat - platelets and WBCs
RBCs - 45%
List the plasma proteins and state what they do
ALBUMINS: viscosity, osmotic pressure, buffer, transports fatty acids, free bilirubin, thyroid hormones
GLOBULINS: transports lipids, carbohydrates, hormones, ions, antibodies, and complement
FIBRINOGEN: Blood clotting
Components of plasma
Ions: osmosis, membrane potentials and acid base balance
Nutrients: glucose, amino acids, triacyglycerol, cholesterol, vitamins
Waste products:
- urea, Urica acid, creatinine, ammonia salts, breakdown products of protein metabolism
- lactic acid. End product of anaerobic respiration
- bilirubin. Breakdown product of RBCs
Gases: oxygen, carbon dioxide, and inert nitrogen
Regulatory substances: hormones, enzymes
What are the formed elements?
- RBCs - biconxave discs, anucleate, contain hempglobin; transports oxygen and carbon dioxide
- WBCs
- granulocytes
- agranulocytes - Platelets (thrombocytes) - cell fragments. Form platelet plugs, release chemicals necessary for blood clotting.
What is haematopoiesis
The process of blood cell production
what are the cells formed from haematopoiesis?
Proerythroblasts: Develop into red blood cells
Myeloblasts: Develop into basophils, neutrophils, eosinophils
Lymphoblasts: Develop into lymphocytes
Monoblasts: Develop into monocytes
Megakaryoblasts: Develop into platelets
what is the anatomy of RBCs
biconcave discs
lack a nucleus and other organelles
cannot reproduce
essentially consist of a plasma membrane, cytosol, and haemoglobin
each contains about 280 million haemoglobin molecules
lack mitochondria
what is the function of RBCs (erythrocytes)?
TRANSPORT
carries oxygen from lungs to tissue: 98.5%
transports Carbon dioxide from tissue to lungs
describe the composition of hemoglobin
- four globin molecules (polypeptide chains): transport carbon dioxide and nitric oxide.
- Four haem molecules, eahc containing one iron atom; transport oxygen
- Iron required for oxygen transport.
what is erythropoietin?
is a hormone produced by the kidney that promotes the formation of red blood cells by the bone marrow, in response to low blood O2 levels.
decribe the production of red blood cells
Stem cells → proerythroblasts → early erythroblasts → intermediate erythroblasts → late erythroblasts → reticulocytes
function of leukocytes
Protect body against microorganisms and remove dead cells and debris
describe the movements of Leukocytes
Ameboid: pseudopods
Diapedesis: cells become thin, elongate and move either between or through endothelial cells of capillaries
Chemotaxis: attraction to and movement toward foreign materials or damaged cells. Accumulation of dead white cells and bacteria is pus
describe erythrocytosis
an increase in RBCs relative to the volume of blood. Polycythemiais an increase in both RBC concentration and hemoglobin, the protein in red blood cells that carries oxygen to the body’s tissues.