Blood 3 and 4 lectures Flashcards
What is the most common formed element in the blood?
Red blood cells
Why are RBCs biconcave? Why are they flexible?
Biconcave shape allows for greater surface area for gas exchange
they are flexible so they can pass through tiny spaces like capillaries
Which type of blood cell lacks most organelles and also lacks a mucleus?
RBCs
WHat is the lifespan of a RBC? Where are they produced?
120 days
bone marrow
Globin conatins two ____ and two _____ subunits
alpha, beta
What is the role of heme?
It contains iron, which oxygen can bind to
One RBC contains about _____ hemoglobin molecules
300 million
In the lungs, hemoglobin picks up____, which binds to the _____forming _______, which is the color _____. Oxygenated blood travels to capillaries where it releases _____, becoming ____ which is the color _____.
oxygen
iron ions
oxyhemoglobin
red
oxygen
deoxyhemoglobin
dark red
Oxygen release depends on the _______ in the surrounding tissues; hemoglobin rarely releases ______
need for oxygen
all of its oxygen
CO2 binds to the _____ in the hemoglobin, forming a molecule known as _____
amino acids
carbaminohemoglobin
What is carboxyhemoglobin?
the molecule that forms when carbon monoxide binds to the hemoglobin instead of carbon dioxide.
Anemia can be casued by what 3 things?
not enough RBCs, not enough hemoglobin, or abnormal hemoglobin
What is sickle cell anemia?
abnormal hemoglobin causes the RBCs to have a weird sickle shape. they therefore do not carry oxygen very well and they can get stuck in capillaries
What is polycythemia?
What are the 2 common causes?
Way to many RBCs which increases the viscosity of the blood which slows down flow.
Causes: bone marrow cancer, or low oxygen at high altitudes
Where are white blood cells produced?
In bone marrow and lymphatic tissue
Leukocytes (WBCs) are split into categories, granulocytes and agranuclocytes. Which types fall into both categories?
Granulocytes: neutrophils, eosinophils, basophils
Agranulocytes: lymphocytes and monocytes
Neutrophils make up what percent of the WBCs in the blood?
What does their nucleus look like?
How long does development take?
What is their lifespan?
What is their function?
40-70%
multilobed nucleus
6-9 days
6 hours to a few days
phagocytize bacteria
Eosinophils make up what percent of the WBCs in the blood?
What does their nucleus look like?
How long does development take?
What is their lifespan?
What is their function?
1-4%
bilobed nucleus
6-9 days
8-12 days
kill parasitic worms, destroy antigen-antibody complexes
Basophils make up what percent of the WBCs in the blood?
What does their nucleus look like?
How long does development take?
What is their lifespan?
What is their function?
0.5%
Lobed
3-7 days
a few hours to a few days
release histamine and other things for imflammation, also contain heparin (an anticogulant)
Lymphocytes make up what percent of the WBCs in the blood?
What does their nucleus look like?
How long does development take?
What is their lifespan?
What is their function?
20-45%
spherical nuclei
days to weeks
hours to years
immune response: direct attack with T cells or antibodies with B cells
Monocytes make up what percent of the WBCs in the blood?
What does their nucleus look like?
How long does development take?
What is their lifespan?
What is their function?
4-8%
U shaped nucleus
2-3 days
months
phagocytosis (macrophages in tissues)
Name all the WBC types in order from most to least abundant
Never: Neutrophils
Let: lympocytes
Monkeys: monocytes
Eat: eosinophils
Bananas: basophils
What is a nrmal leukocyte count?
4000-11,000 per microlitre
What is luekopenia?
How about leukocytosis?
less leukocytes than normal
more leukocytes than normal
What is leukemia?
condition of cancerous white blood cells. they reproduce uncontrollably in the bone marrow
What is haematopoiesis?
the formation of blood cells
On average, _____ billion blood cells are made each day
100 billion
What is erythropoesis?
formation of RBCs in the bone marrow
Why are mature RBCs smaller than immature ones?
Because they lose their organelles and nucleus, making them smaller
How does erythropoietin regulate erythropoiesis?
When there is decreased renal blood oxygen content, the kidney will release erythropoietin which then stimulates erythrocyte production in the bone marrow
What causes a drop in renal blood oxygen levels?
a low number of RBCs due to hemorrhage ot RBC desctruvtion
reduced oxygen in the environment like high altitudes or pneumonia
increased demand for oxygen like exercise
Where are platelets made? They are a fragment of what king of cell?
in the bone marrow
megakaryocyte
After entering circulation, about ____ of platelets migrate to the speel for storage and are released in response to ______
1/3
rupture in blood vessel
What is hemostasis?
when the body seals a broken blood vessel and prevents blood loss
What are the 3 steps in hemostasis and what happens at each?
Vascular spasm: platelets secrete vasoconsrtictors to prevent blood loss
platelet plug: collagen fibers are exposed and platelets become sticky and release chemicals to attract even more platelets. then the plug is formed
Coagulation: clotting factors in the blood reinforce platelet plug, thrombin joints fibrinogen proetins into a net like structure called fibrin. you need calcium for this
Clotting factors are secreted primarily by the ___ which requires ____ to produce many of them. many clotting factors also require ____ ions
liver, vitamin K, calcium
What happens in stage 1 of coagulation?
the production of active thrombokinase from either the instrinsic or extrinsic pathways
What is the instrinic pathway of coagulation activated by?
What is the extrsinsic pathway activated by?
surface contact. these molecules are already floating around in the blood plasma
chemicals released from the damaged tissues themselves
What occurs in stage 2 of coagulation?
conversion of prothrombin to thrombin by thrombokinase produced in stage 1
What occurs in stage 3 of coagulation?
conversion of fibinogen to fibrin by thrombin (produced in stage 2), and production of the fibrin clot
Fibrinogen is made in the ____, and is a part of the ____ pathway, converted into ____
liver
common
fibrin
Prothrombin is made in the ____ which requires _____, is a part of the _____ pathway and is converted to _____
liver
vitamin K
common
thrombin
What conditions hasten clotting?
rough spots in blood vessel lining
slower than normal blood flow
What conditions oppose clotting?
smooth lining of blood vessel surfaces (dont allow platelets to stick)
substances in the blood that inactivate thrombin (like heparin)
PLasminogen is converted into _____, which is responsible for_____
plasmin
dissolving the clot
what is thrombosis?
abnormal clotting in a vessel that is not broken
What is a thrombus?
What about an embolus?
a clot that attaches to the blood vessel wall
the blood clot comes off the wall and begins travelling thru the blood stream
what is an embolism?
a blockage of blood flow from an embolus lodges in a vessel
What is infarction?
cell dealth due to embolism blocking blood blow
What is thrombocytopenia?
having not enough platelets which causes spontaneous bleeding from small vessels all over the body
Why does impaired liver function lead to a bleeding disorder?
because the liver makes cofactors for clotting
the aPTT test helps identify if the ____ pathway is working and the PT test helps identify if the ____pathway is working
instrinsic
extrinsic
explain how the PT test works
patient blood plasma is added to a source of tissue factor, which converts prothrombin to thrombin. The time it takes to clot is known as the prothrombin time. If this time is prolonged, we know there is an issue with once of the factors involved in the extrinsic pathway ( VII, X, V, prothrombin, or fibrinogen)
explain the aPTT test
you add substances that activate the instrinic pathway, and then time until a clot forms is measured. if the time is prolonged, we know one of the cofactors in the instrinsic pathay is not functioning (XII, XI, VIII, IX)
If the PT clot time was prolonged and the aPTT time was normal, what pathway is affected?
extrinsic
If the PT time is normal and the aPPT time is prolonged, what pathway is affected?
intrinsic?
review this
https://www.youtube.com/watch?v=cy3a__OOa2M
