Chapter 17 up to hemostasis Flashcards
What are the two components blood is made of? and what is the percentage of each?
- plasma (fluid matrix) - 55%
2. formed elements (cells) - 45%
What are the 3 formed elements called and describe?
- erythrocytes - red blood cells
- leukocytes - white blood cells
- thrombocytes - platelets
What is the consistency of blood?
sticky, opaque, and salty
Describe the color of blood when there is a high content of O2 vs a low content of O2.
- high O2 = bright red
2. low O2 = dark red
What is the pH of blood?
7.35 - 7.45 (slightly basic)
What is the core temperature?
38 degrees (core) 37 degrees (periphery)
What portion of body weight does blood make up in the body?
8%
What is the average volume in males vs females?
- females - 4-5L
2. males - 5-6L
Name 3 general functions that blood is responsible for.
- transports
- regulates
- protects
What are 3 things that blood transports?
- oxygen, nutrients
- waste products
- hormones, other molecules
What are 3 things that blood regulates?
- temperature
- pH
- blood volume - maintains blood pressure
What are 2 ways that blood protects?
- blood loss - hemostasis (blood clotting)
2. fights infection
Describe hemostasis generally
plasma proteins and platelets initiate clot formation
Describe 3 ways how blood fights infection
- WBC’s defend against foreign invaders (macrophages)
- antibodies - produced by lymphocytes
- complement proteins in plasma
What is the percentage of water that makes up the blood plasma?
90%
What is the percentage of proteins that makes up the blood plasma?
8%
Describe the breakdown of the 8% of proteins in the blood plasma. What 3 proteins are they and what percent do they make up?
- Albumin - 60%
- globulins - 36%
- clotting proteins - 4%
Name the 3 functions of albumin
- maintains osmotic balance of blood
- carrier proteins
- pH buffers - stabilize pH
Name the 2 functions of globulins
- transport proteins (eg. hemoglobin)
2. antibodies - gamma globulins
Name the 2 clotting proteins
- fibrinogen
2. prothrombin
What is the last 2 percent of blood plasma made up of?
dissolved materials
eg. nitrogenous wastes, ions, gases, hormones
How large are erythrocytes? and what are they made of?
7.5 microns in diameter
biconcave discs
Do erythrocytes have a nucleus?
no nucleus - anucleate
What happens when they mature and fill with hemoglobin?
They lose most of their organelles
What is the most numerous formed element? and what do they make up in the females vs the males?
erythrocytes
females - 4.3 - 5.5 million microlitres
males - 5.1 - 5.8 million microlitres
What do erythrocytes use to produce ATP?
anaerobic respiration
What enables erythrocytes the squeeze through tiny capillaries?
they have flexible protein skeleton so they can change shape
How much hemoglobin makes up a erythrocyte? and what is it adapted for?
- 97% hemoglobin
2. adapted for gas transport
What are the 3 main functions of erythorocytes (RBCs)?
- dedicated to respiratory gas transport - carries O2
- iron binds reversibly with O2 -> oxyhemoglobin
- globin binds reversibly with CO2 -> carbaminohemoglobin
What is the hemoglobin structure made of?
protein globin: two alpha and two beta chains
Where does the heme pigment bind onto?
each globin chain
Where can the iron atom in each heme bind to?
one O2 molecule
How many molecules of O2 can be transported by each hemoglobin?
4 molecules
How many molecules of hemoglobin does each RBC contain?
125,000,000
How many O2 molecules can one RBC carry?
one billion oxygen molecules
What does oxygen loading in the lungs produce? describe its color
oxyhemoglobin (ruby red)
What does oxygen unloading in the tissues produce? describe its color
reduced hemoglobin (dark red)
deoxyhemoglobin
What does CO2 loading in the tissues produce?
carbaminohemoglobin
What is blood cell formation called?
hematopoiesis
Where does hematopoiesis occur?
in red bone marrow
- girdles of axial skeleton
- proximal epiphyses of humerus and femur
What do hemocytoblasts (hemotopoietic stem cells) do?
- give rise to all formed elements
2. hormones control development
What is erythropoiesis?
red blood cell production
What are the 8 phases in erythropoiesis development?
- hemocytoblast
- proerythroblast
- early erythroblast
- late erythroblast
- normoblast
- reticulocyte
- erythrocyte
- released into circulating blood
What stimulates erythropoiesis?
erythropoietin (EPO) - hormone produced mainly by kidneys in response to hypoxia. Liver produces EPO too.
What is hypoxia?
decreased oxygen content of blood
What are the effects of EPO?
more rapid maturation and release of erythrocytes from red marrow
What dietary requirement is needed for erythropoiesis and specifically heme synthesis?
iron
What is needed for iron absorption?
vitamin B12 and folic acid
What is needed for globin synthesis?
amino acids and other nutrients
Describe the destruction of erythrocytes starting with their lifespan?
- life span 100-120 days
- old RBCs become fragile, and Hb begins to degenerate
- they have no nucleus or organelles so they are unable to synthesize proteins or complete cell repair
- macrophages engulf dying RBC’s in the spleen
- heme and globin are separated
- heme is split: iron is recycled and remainder of heme -> bilirubin -> bile -> stercoblin -> feces
- globin is recycled - amino acids used to synthesize new proteins.
What does too few RBC’s lead to?
hypoxia
What happens if there are too many RBCs?
increases blood viscosity - harder to pump
What depends on the balance between RBC production and destruction?
EPO
What are erythrocyte disorders causing hypoxia called?
anemias
What are 4 signs and/or symptoms of anemia?
- fatigue
- paleness
- shortness of breath
- chills
What are the 3 causes of anemia?
- insufficient erythrocytes
- low hemoglobin
- abnormal hemoglobin
What is hemorrhagic anemia?
acute or chronic blood loss
What is hemolytic anemia?
RBCs rupture prematurely
What is aplastic anemia?
destruction or inhibition of red bone marrow
What does a lack of EPO indicate?
kidney failure
What might cause iron deficiency anemia?
inadequate diet - impaired iron absorption
What is pernicious anemia?
lack of intrinsic factor prevents absorption of Vitamin B12 which is necessary for iron absorption from digestive tract
What are two genetic conditions cause by abnormal hemoglobin and are types of anemias?
- sickle cell anemia
2. thalassemias
Describe what happens with sickle cell anemia
- defective gene codes for abnormal hemoglobin
- hemoglobin becomes rigid
- causes RBCs to become sickle shaped in low oxygen situations
- can not pass through small capillaries - hypoxia
Describe what happens with thalassemias
- absent or faulty globin chain
2. RBCs are thin, delicate and deficient in hemoglobin
Name one other erythrocyte disorder and describe it.
polycythemia
excessive RBCs causes increase blood viscosity
What is a result from polycythemia vera?
bone marrow cancer
When does seconday polycythemia occur?
less O2 is available or when EPO production increases
What do athletes do to enhance RBC production?
blood doping - injecting EPO
What is a problem that can arise from blood doping?
can lead to heart failure
What is different from a leukocyte compared to a erythrocyte?
leukocytes have nucleated cells
What is the percent of blood volume leukocytes take up?
1%
What do most leukocytes use the bloodstream for?
transportation
How do the leukocytes move out of the capillaries?
diapedesis
What is it called if there is over 11,000 microlitres of leukoocytes?
leukocytosis
What is the lifespan of a leukocyte?
days to years (some last a whole lifetime)
What are the two types of leukocytes?
- granulocytes
2. agranulocytes
Describe granulocytes
have visible cytoplasmic granules when stained with Wright’s stain
Describe agranulocytes
have no visible cytoplasmic granules
Name 3 granulocytes
- neutrophils
- eosinophils
- basophils
Name 2 agranulocytes
- monocytes
2. lymphocytes
What is the most numerous WBC?
neutrophils
What type of nucleus does the neutrophil have?
multi lobed nucleus
What do the granules contain in the neutrophils?
hydrolytic enzymes
What type of WBC is the first responder to site of injury or infections?
neutrophils
What type of WBC is common in parasitic infections?
eosinophils
What types of WBC are strongly phagocytic?
neutrophils
What types of WBCs are weak phogocytizers?
eosinophils
How do they digest worms?
release hydrolytic enzyme and eat worms from the outside
What do eosinophils help to moderate?
immune responses
reduce severity of allergic responses
What are the rarest WBCs?
basophils
Describe what the granules of a basophil look like.
large, purplish-black granules
What do the large, purplish-black granules contain?
histamine an inflammatory chemical that attracts other WBCs to the inflamed sites
What else do basophils release?
heparin an anticoagulant
Where are lymphocytes found?
lymphoid tissue, and also circulate in the blood
What are the two types of cells found with lymphocytes? and describe
T-cells - initiate immune response
B-cells - produce antibodies - gamma globulin
What is the larges leukocyte?
monocyte
What color is the cytoplasm of the monocyte?
pale-blue
What do monocytes turn into?
macrophages - “big eaters”
What is the production of WBCs called?
leukopoiesis
What is the production of WBCs stimulated by?
chemical messengers from bone marrow and mature WBCs
What do all leukocytes originate from:
hemocytoblasts
Name two types of stems cells for WBC?
myeloid
lymphoid
What does myeloid produce?
neutrophils, monocytes, eosinophils, basophils
What does lymphoid produce?
lymphocytes
Name all the lymphocytes from in order of relative number
neutrophils lymphocytes monocytes eosinophils basophils
Name three leukocyte disorders
leukopenia
leukemias
mononucleosis
Describe leukopenia
abnormally low WBC count
Describe leukemias
too many WBCs
Describe what causes bleeding in leukemia (3 points)
- bone marrow occupied with cancerous lymphocytes
- immature nonfunctional WBCs released into the bloodstream
- insufficient RBCs and platelets produced
What causes death in leukemia?
internal hemorrhaging and overwhelming infections
What is the lifespan of a thrombocyte?
5-9 days
What do the granules contain in the platelets?
- serotonin
- Ca2
- enzymes
- ADP
- platelet derived growth factor (PDGF)
What do platelets initiate
hemostasis - blood clotting
