Blood Components and Blood Clotting Flashcards
What is the average blood volume for women?
5.0 L
What is the average blood volume for men?
5.5 L
Name the 4 components of blood.
- plasma
- erythrocytes: hematocrit
- leukocytes
- platelets
How much plasma is there in blood?
3 L
Erythrocytes make up what percent of blood in men?
42-52%
Erythrocytes make up what percent of blood in women?
37-47%
Plasma without clotting factors is called:
serum
Plasma is ____ % water and ____% proteins.
90% water and 6-8% proteins
Plasma contains:
- water
- gases
- small proteins
- nutrients
- electrolytes
What small proteins are in plasma?
- clotting proteins
- albumin (osmotic pressure gradient)
What electrolytes are in plasma?
- Na+ and Cl–
- H+, HCO3–, K+, and Ca2+
How many RBCs/mL of blood?
5 billion
Describe the shape of RBCs.
- biconcave disk
- large surface area
- favours diffusion
Describe the diameter of RBCs.
8 μm
Describe the thickness of RBCs.
2 μm
Continuous glucose supply to the RBC via _____ _____.
facilitated diffusion
How does glycolysis play a role in RBCs?
produces ATP necessary for function
RBCs play a role in:
- vessel dilation (in response to shear stress)
- formation of NO
Describe the hemoglobin molecule.
- Iron-containing
- Binds: O2, CO2, H+, and CO
Describe O2 transport via hemoglobin.
- 98.5% is bound to Hb
- 1.5% is dissolved in plasma
Describe CO2 transport via hemoglobin.
- Converted to bicarbonate
- Dissolved in plasma
- Bound to Hb
Oxygenated Hb is ____ ____.
bright red
deoxygenated Hb is ____ ____.
dark red
Erythrocytes have no:
- DNA
- RNA
- organelles
- no division of mature RBCs
Describe the life span of erythrocytes.
short life span = 120 days
We replace ______ RBCs/sec, which = ______ /day
- 2-3 million RBCs/sec
- = 200 billion/day
Where are erythrocytes synthesized?
red bone marrow
What is the process of erythrocyte synthesis called?
erythropoiesis
What happens to old RBCs?
- filtering and destruction of erythrocytes
- spleen filters and removes old erythrocytes
- liver metabolizes by-products
_____ triggers differentiation of stem cells to erythrocytes.
erythropoietin
Developing erythrocytes produce _____.
hemoglobin
Developing erythrocytes lose ____ and _____.
nuclei and organelles
_____ and _____ develop from the same stem cells in bone marrow. What are these stem cells called?
- erythrocytes and leukocytes
- hematopoietic stem cells
Erythrocyte synthesis is stimulated by _____.
erythropoietin
Erythropoietin is secreted from:
kidneys under conditions of low oxygen levels in blood flowing to kidneys
What are the 3 requirements for erythrocyte production?
- iron
- folic acid
- vitamin B12
Iron is a component of ______.
hemoglobin (heme portion)
Normal hemoglobin content of blood for men is:
13-18 g/dL
Normal hemoglobin content of blood for women is:
12-16 g/dL
Folic acid is necessary for:
DNA replication and thus cell proliferation
Vitamin B12 is necessary for:
DNA replication and thus cell proliferation
Spleen macrophages filter blood by:
phagocytosis of old, fragile RBCs
Describe how hemoglobin is catabolized in the spleen.
- After iron removed, heme → bilirubin
- Bilirubin is released into bloodstream
- Travels to liver for further metabolism
- Products of bilirubin catabolism are (1) secreted in bile and travel to the intestinal tract or (2) released into the bloodstream and excreted in urine
What happens to iron afterwards?
recycled for synthesis of new hemoglobin
Iron is transported in blood bound to ______. From ___ to ____ _____.
- transferrin
- From GI tract to bone marrow
- From liver to bone marrow
Iron is stored bound to _____, in where?
- ferritin
- liver
- spleen
- small intestine
What happens when there is damage to a blood vessel?
- vessel constricts to minimize blood loss (vascular spasm)
- intrinsic vascular response
- sympathetic innervation
- endothelial layer becomes sticky
Platelets=
thrombocytes
What is the function of the platelet (thrombocytes) plug?
- forms around the site of vessel damage
- decreases blood loss
- necessary for production of a blood clot
What 2 things prevent the spread of a platelet plug?
- Prostacyclin (PGI2)
- nitric oxide
Prostacyclin (PGI2) is ____ ___ healthy endothelial cells.
produced in
Nitric oxide is ____ ___ healthy endothelial cells.
released by
Describe the steps of the platelet plug: platelet adhesion.
- blood vessel damage
- exposure of subendothelium
- Von Willebrand factor binds to collagen fibres
- Platelets bind to vWf
- platelet adhesion, sticky, secretions
vWf is found in:
- plasma
- endothelial layer = increased stickiness
Secretions for the platelet plug causes:
vasoconstriction
Aggregated platelets release 5 secretory products. What are they?
- ADP
- serotonin
- epinephrine
- coagulation chemicals
- thromboxane A2 (positive feedback)
What does ADP do for the platelet plug?
increases stickiness (positive feedback)
What does serotonin do for the platelet plug?
vasoconstriction
What does epinephrine do for the platelet plug?
vasoconstriction
Aggregation of platelet plugs is a _____ feedback mechanism.
positive
Clotting =
coagulation
Describe coagulation.
- gel-like (thrombus)
- occurs around platelet plug
Signals by what lead to formation of blood clot?
aggregated platelets + fibrin
The coagulation cascade is ____ feedback.
positive feedback (thrombin regulates its own activation)
What do plasminogen activators do?
convert plasminogen to plasmin
Give an example of plasminogen activators.
- tissue plasminogen activator
- Secreted by endothelial cells during clot formation
- Activated by fibrin
Clotting factors produced by the _____.
liver
Clotting factors are secreted into ______ in _____ form.
blood in inactive form
Clotting factors are activated during ______.
cascade
Name a factor that limits clot formation.
anticoagulants
What are anticoagulants?
proteins in plasma and on the surface of endothelial cells
How does aspirin affect platelet aggregation in low doses?
- anitcoagulant
- decreases platelet aggregation
How does aspirin affect platelet aggregation in high doses?
- increases platelet aggregation
- limits formation of prostaglandin (a clot inhibitor) and can induce clot formation
EPO =
erythropoietin
_____ and _____ increase with exercise (endurance training). Increases of ___% over sedentary individuals are reported.
- plasma volume and red cell volume
- 30%
High blood volume =
high VO2 max (regardless of training)
Heavy intensity exercise increases the stimulus for both _____ and ______.
plasma volume and RBC expansion
Albumin increase =
- greater movement into vessels
- increased synthesis by the liver
- decreased movement out of vessels (impact on osmotic pressure gradient)
Increased aldosterone, ADH =
increased sodium and water retention following exercise and reduced excretion of water and sodium
EPO increases by ____x’s value (sea level vs altitude >4000m) after ___ days. New RBCs at _____ days
- 8x
- 3 days
- 5-7 days
Why does blood volume change occur at sea level?
- due to hormones
- GH
- intensity and duration dependent
What are the 5 types of leukocytes?
- neutrophils
- eosinophils
- basophils
- monocytes
- lymphocytes
Describe the synthesis of leukocytes.
- Hematopoietic stem cells
- Full maturity in bone marrow (Except: T cells)
- To thymus
All types of leukocytes are formed from:
hematopoietic stem cells
Describe neutrophils.
- Represent 50–80% of leukocytes in blood
- Phagocytes
- Circulate in blood for 7–10 hours
- Migrate to tissues for a few days
- numbers increase during infections
Describe eosinophils.
- Represent 1–4% of leukocytes
- Phagocytes (but not main mechanism of action)
- Defend against parasitic invaders (e.g., parasitic worms)
- Granules contain toxic molecules that attack parasites
Describe basophils.
- Represent less than 1% of leukocytes
- Nonphagocytic
- May defend against large parasites by releasing toxic substances
- Contribute to allergic reactions
- Histamine
- Heparin
Describe monocytes.
- Represent 5% of leukocytes
- Phagocytes
- New monocytes circulate in blood for a few hours
- Migrate to tissues and become macrophages (wandering and fixed macrophages)
Describe lymphocytes.
- Represent 30% of leukocytes
- Represent 99% of interstitial fluid cells
What are the 3 types of lymphocytes?
- B lymphocytes (B cells)
- T lymphocytes (T cells)
- Null cells (most are Natural Killer cells (NK))
Leukocytes function in:
defence of body
Leukocytes are part of the ___ _____.
immune system
Leukocytes defend against:
pathogens
Leukocytes identify and destroy _____ _____.
cancer cells
Leukocytes perform ______ of debris from dead or injured cells.
phagocytosis
B cells are associated with _____.
antibodies
What do antibodies do?
mark invaders for destruction
What secretes antibodies?
plasma cells
Describe T cells.
- Directly damage foreign cells
- Contact infected, mutant, or transplanted cells
- Develop into cytotoxic T cells that destroy target cells
(Takes several days) - Secretory products form pores in the target cell’s membrane
Lysis occurs
Describe Null cells.
- Most are natural killer cells
- Important against viral infections
- Attack virus-infected cells, causing lysis
- Fast acting—early immune response
