BLOOD LECTURE Flashcards
Understanding the functions and properties of blood.
General Functions of Blood
transportation, protection, and regulation
How much blood do men have in comparison to women? pH balance?
women 4-5L; men 5-6L and both have a pH of 7.35-7.45
What are the components of whole blood?
plasma, buffy coat (leukocytes and platelets), erythrocytes (red blood cells)
What percentage of whole blood do erythrocytes make up?
45% of whole blood
What percentage of whole blood does plasma make up?
55% of whole blood
What percentage of whole blood do leukocytes (white blood cells) make up?
<1% of whole blood
What are the different types of leukocytes?
granulocytes and agranulocytes
What are the different types of granulocytes?
neutrophils, eosinophils, and basophils
What are the different types of agranulocytes?
lymphocytes and monocytes
What is viscosity?
the thickness of a fluid
What is the result of high blood viscosity on the body?
If the blood became overly viscous it would become more difficult for the heart to pump and result in the heart working harder to transport oxygen; strains heart causing low heart rate
What is the result of low blood viscosity on the body?
If the blood had a low viscosity level or was too thin the heart rate would accelerate because fluids would be moving too quickly throughout the body; blood pressure drops
What is osmolarity?
the number of dissolved particles in a fluid
What is blood’s osmolarity?
blood = 280-296mOsm/L mostly because of the nutrients and protein it contains
What does whole blood transport?
oxygen, carbon dioxide, nutrients, waste, hormones, and heat
What does whole blood protect with/ against?
whole blood uses leukocytes (white blood cells) to fight against antibodies, clotting, and inflammation
What does whole blood regulate?
water balance and stabilizes pH balance
Kwashiorkor
a lack of protein in the body that causes fluid to accumulate in the abdomen
What are the components of plasma?
water, proteins, enzymes, nutrients, wastes, hormones, and gases
Types of Proteins in Plasma
albumins, globulins, and fibrinogen
What is the most abundant solute in plasma?
proteins; used for clotting, defense, and transport
What are albumins?
the smallest and most abundant plasma proteins which are also most responsible for blood osmolarity and transportation
Components of Plasma Nutrients
glucose, AA, fats, cholesterol, phospholipids, vitamins, and minerals; absorbed by the digestive tract
Components of Plasma Electrolytes
sodium accounts for more blood osmolarity than any other solute (90% of cations)
Components of Plasma Waste
toxic end products of catabolism; urea
Hematopoiesis
the production of all types of blood cells; red, white, and platelets
Where does hematopoiesis occur?
hematopoiesis primarily occurs in the red bone marrow of flat bones
Types of Hematopoiesis
erythropoiesis, leukopoiesis, and thrombopoiesis
Erythropoiesis
the production of red blood cells (erythrocytes)
Leukopoiesis
the production of white blood cells (leukocytes)
Thrombopoiesis
the production of platelets
How many red blood cells per second does erythropoiesis produce?
produces approx. 3 million per second; destroys approx. 3 million per second to maintain homeostasis
What is the creation process for erythrocytes (red blood cells)?
hemocytoblast (stem cell) -> proerythroblast -> erythroblast -> normoblast -> reticulocyte -> erythrocyte
How long does it take for an erythrocyte to develop?
3-5 days involving the reduction in cell size, synthesis of hemoglobin, and loss of nucleus
What is the result of a low blood cell count?
a blood cell count results in hypoxemia (oxygen deficiency in blood) to kidneys
What is the kidneys response to a low blood count?
the kidneys release erythropoietin (EPO) to stimulate the bone marrow and increase the red blood count; takes 3-4 days
What is the main nutritional requirement for erythropoiesis?
iron; urination, defecation, and bleeding are the main causes of iron loss
What are natural stimulants of erythropoiesis?
being at high altitudes, an increase in exercise, or blood vessel hemorrhaging
How much iron do men need in comparison to women?
men 0.9mg/day; women 1.7mg/day; it’s suggested that the individual takes much more than is nutritionally recommended
Why should individuals consume so much iron?
because it is absorbed very slowly and sometimes not at all
How is iron converted within the body?
stomach acid coverts Fe+3 into Fe+2 and then it’s absorbed into the blood; it is then used to make hemoglobin (bone marrow) and myoglobin (muscle)
What are B12 and Folic Acid used for?
rapid cell division
What are Vitamin C and Copper used for?
they are cofactors for enzymes synthesizing in red blood cells
What are Leukocytes?
different variations of white blood cells
What is the process of leukocyte production?
mature leukocytes release CSF in response to infections that stimulate white blood cell (leukocyte) production
Where are leukocytes stored?
leukocytes are stored in red bone marrow (10-20 times as much as erythrocytes); bone marrow releases the granulocytes and monocytes when needed
Life Span of Granulocytes
they stay in the bloodstream for 8 hours until they return into the tissue; only live 5 days after the infection is gone
Life Span of Monocytes
they stay in the bloodstream after 20 hours until they transform into macrophages; may live on for years
Life Span of Lymphocytes
may last decades circulating between blood, tissue, and lymph nodes; provide long-term immunity
What is the process of platelet production (thrombopoiesis)?
hemocytoblast develops receptor for thrombopoietin from liver or kidney and becomes a megakaryoblast
Megakaryoblast
repeatedly replicates its DNA without dividing to form a giant cell called a megakaryocyte; in the bone marrow
What are the functions of a megakaryocyte
cytoplasm folds into itself and splits off cell fragments that enter the bloodstream as platelets
How long do platelets live?
10 days
Where are platelets stored?
they’re stored in the spleen and are released when needed
Form of Erythrocytes
disc-shaped red blood cells that transport gases
Function of Erythrocytes
transports gases like oxygen and carbon dioxide; also contain hemoglobin
Components of Erythrocytes
an increased surface/ volume ratio due to lack of organelles
increases the diffusion rate of substances in/ out of the cell