Blood Flashcards
list the 9 functions of blood
- distribution of nutrients
- oxygen transport
- CO2 transport
- transport of waste products
- hormone transport
- body temperature control
- maintain pH of body fluids
- blood loss prevention
- defense of body against disease
list and describe the 3 components of blood
- formed elements: RBCs, WBCs, platelets
- plasma: fluid portion
- buffy coat
what is the main component of plasma?
water
list the 7 components of plasma
- water
- proteins
- nutrients: glucose, fatty acids, vitamins and minerals
- electrolytes: Na+, K+, Ca+
- hormones
- buffers: bicarbonate
- waste products: urea
list the 3 proteins found in plasma and describe if needed
- albumin
- globulins: antibodies are immunoglobulins
- fibinogen: plays a role in clotting
why do you need to include an anticoagulant when collecting plasma?
since it contain fibrinogen, it will clot unless an anticoagulant is present
what is serum?
all components of plasma except fibrinogen, no anticoagulant needed when collecting
list the 3 formed elements
- erythrocytes (RBCs): 45% of blood
- leukocytes (WBCs): 5 types
- thrombocytes (platelets): clotting, cell fragments
what is hematopoiesis?
formation and development of the formed elements of blood in the red bone marrow
what are hematopoietins?
chemical signals that determine the formation of formed elements
describe the structure of erythrocytes
biconcave disks with no nuclei (except for in chickens) meaning they have a finite lifespan
what is hemoglobin?
a major component of RBCs, consists of 1 globin protein and 4 heme groups, with each heme group containing an iron (Fe2+ ferrous) that LOOSELY and REVERSIBLY binds to oxygen
what do erythrocytes do?
transport O2 from lungs throughout body and CO2 from cells in the body to the lungs
when does oxyhemoglobin form?
when O2 binds to hemoglobin in the lungs
when does carbaminohemoglobin form?
when CO2 binds to hemoglobin
when does carboxyhemoglobin form and why is it bad?
when carbon monoxide (CO) binds very tightly to hemoglobin, prevents O2 from binding to hemoglobin = no O2 transport = suffocation
what is nitrate poisoning?
when nitrate converts ferrous iron (Fe2+) to ferric iron (Fe3+), which can’t bind to oxygen, forming methemoglobin, turning blood a chocolate color
where is nitrate found, which can cause nitrate poisoning?
on freshly fertilized pastures
what is erythropoiesis?
formation of erythrocytes
what is erythropoiesis stimulated by?
erythropoietin, which is produced by kidney cells
when is erythropoietin released?
when kidneys sense decreased O2 delivery and release erythropoietin, which stimulates erythropoiesis in red bone marrow, leading to the production of RBCs
how is the release of erythropoietin stopped?
more erythrocytes will deliver O2 to kidneys, which inhibits further release of erythropoietin (negative feedback)
how are erythrocytes removed from circulation (broad)
by macrophages in the liver and spleen, which perform phagocytosis
describe what happens to the globin protein when hemoglobin is broken down
the globin protein is broken down into amino acids that are used for new protein synthesis
describe what happens to the iron from the heme group when hemoglobin is broken down
iron is transported through blood, bound to transferrin, then stored in the liver as ferritin, or used by red bone marrow for erythropoiesis
describe what happens to the heme group when hemoglobin is broken down
the heme group is converted to biliverdin (green), then to bilirubin (yellow), which is then incorporated into bile in the liver
what happens to bile once it leaves the liver?
it is secreted into the small intestine, and then reacts with bacteria in the large intestine, which gives feces it characteristic color, or it leaves the kidneys through urine
list 6 conditions of RBCs
- icterus/jaundice
- hemoglobinemia
- hemoglobinuria
- hemogglutination
- anemia
- polycythemia
describe icterus/jaundice
yellow discoloration of skin and mucus membranes
what causes icterus/jaundice?
bilirubin builds up in blood, caused by liver damage or bile duct damage, or increased rate of erythrocyte destruction