Slide 6 Flashcards
What is atherosclerosis?
formation of plaque between the inside walls from lipids (LDL-deliver to peripheral tissue and HDL - pick up from peripheral tissues)
What is the issue with high LDL?
It indicates a lot of lipid deposits in tissue.
What is an angioplasty and what is the issue with it?
Widens size of artery. It affects the integrity of blood vessels.
What is the constituents of a blood vessel?
in a closed circulation
the elements representing the whole blood =hematocrit (whole blood volume is plasma (fluid)+formed elements (cells)
plasma: 55%
formed elements: 45%
plasma: protein 6%, water 92%, other solutions 2%
What are the proteins for in the plasma?
- albumen: 58% act as transport proteins and exerting blood osmotic pressure (pressure to drop fluid back into blood vessel at the tissue level)
- globulins: immune=for immune cells, also a transport protein
- fibrinogen: always circulates in blood as inactive form and then will be activated needed for blood clot (forms a mesh)
What is the constituents of formed elements?
- buffy coat: between formed elements and plasma
containing leukocytes: neutrophils, lymphocytes, monocytes, eosinophils and basophils
What additional factors affect composition of blood? (eg. if you are athlete)
drug use and altitude
Compare the permeability of blood vessels.
arteries: away
veins: back to heart (venir)
arteries: not permeable
capillaries: permeable
What is the (colloid) blood osmotic pressure?
driving force that brings the fluid back in (albumin is an important contributor)
What is the capillary hydrostatic pressure and what is the driving force?
force pushing the fluid out which is determined by the heart
Describe the flow of blood from artery to capillary.
High pressure blood comes from the arteries flow into the capillaries (which are permeable) so fluid flows out and the pressure drops drastically. Some plasma proteins (omnipresent in the blood) are a big contributor to the pull of blood back into the blood vessel.
What are platelets involved in?
coagulation
What is the structure of RBCs?
biconcave disk
(the middle can be seen through in the microscop)- to increase surface area and flexibility so it can bend easily
-7.5 micrometer
-spectrin:
1)cytoskeleton protein that binds to the membrane
2) responble partially for the elastic strength when going through deformation
3) consists of two intertwined polypeptide chains (alpha and beta) with flexible link between domains and phosphate groups
What is the function of the cytoskeleton in relation to RBCs?
the cytoskeleton has attachment proteins?
Describe the structure of hemoglobin and its abundance in a RBC. State the effect of anemia on iron and oxygen levels.
200-300 hemoglobin per erythrocyte
- has 4 heme groups
- each heme group can bind with oxygen (and CO2 but at different locations)
- anemia: causes iron deficiency which will cause deficiency in oxygen
What is the process of RBC differentiation?
mature RBC have no nucleus
- takes 4 days to mature fully
- begins with proerythroblasts
- mitotic divisions to make
- basophilic erythroblasts
- more differentiation
- produces polychromatic
- erythroblasts
- start producing hemoglobin where they lose their nuclei and become reticulocytes
- 24-36 hours to mature once released in blood
Where does erythropoiesis occur?
bone marrow
Describe the path of a stem cell to neutrophil.
From stem cell, matures into neutrophil where it enters the blood stream and squeeze through the pores of the capillaries to get through. Once they enter, they become mature cell type.
Why does bone regenerate well?
because of the presence of so many blood vessels (stem cell use)
What are platelets?
cell fragments which arise from megakaryocytes.
What are bone marrow stem cells susceptible to?
depression drugs and radiation therapy
What is leukopenia?
reduction of WBCs which leaves the person open to many infections
What is thrombocytopenia?
a reduction in the production of platelets leaving the person at high risk for hemorrhage.
What is the serious form of the conditions where there is a reduced production of RBC?
plastic anemia
How is erythropoiesis stimulated?
by low levels of oxygen, kidneys release glycoprotein erythropoietin (hormone) to stimulate bone marrows for faster RBC production and speed maturation of RBCs
What happens to erythropoiesis when altitudes are higher?
stimulates erythropoiesis because of low oxygen levels which is why athletes train at high altitudes
What is the turnover of RBCs?
120 days
macrophage phagocytose
36:29
What is the turnover of RBCs?
120 days
macrophage phagocytosis the aged or abnormal RBC
-breakdown of hemoglobin to amino acids, iron and pigmented bilirubin
-iron returned to bone marrow for new hemoglobulin synthesis
-bilirubin transported to liver to be excreted into intestines as bile
-amino acids used for energy or new protein synthesis
Describe iron homeostasis and metabolism
Obtain iron from diet and absorbed by active transport and then transferrin protein transports it into plasma.
What does the liver do with excess iron? and what happens to bilirubin?
- stores as ferritin
- make hemoglobin
- bilirubin can be excreted into feces and urine via kidneys
What does the hematocrit concentration indicate?
packed cell volume
anemic person: has less hematocrit (less PCV)
polycythemia: has more hematocrit (increased PCV)
normal concentration varies
How can we find the hematocrit?
let blood stand or spun by centrifugations to incur the separation of blood components
How can you recognize neutrophils?
bigger than RBC
multi lobed nucleus
How can you distinguish granulocytes?
granules (-phils) while monocytes and lymphocytes are agranular (no visible granules)
What is the difference in structure and physically of normal RBCs and iron-deficient ones?
not uniform in size
Compare granulocytes profiles.
neutrophils: 65% (most abundant)
can squeeze through tiny
-> diapedesis:capillary pore to get into tissue they need to
first one on the site of damage and most abundant
eosinophils: 2-5% circulating WBC
protection against parasite
allergic reactions by releasing inflammatory substances
basophils: 0.5-1%
histamine: inflammatory, causes more blood flow to area
diapedesis
Compare agranulocyte profiles.
lymphocytes: smallest of WRB, second most numerous
account 25% of WBC
make up specific/adaptive immunity –> B (produce antibodies against specific antigens) and T (directly attack infected/cancer cells) lymphocytes
produced in the bone marrow but T cells mature in thymus.
(T attack, B produce antibodies)
monocytes:
What is innate/non specific and adaptive/acquired immunity?
B & T cells: adaptive immunity
- specific response to pathogens
- B and T cells for tuberculosis for example (generate vaccines using these)
- acquired, not written in DNA
Natural killer cells: innate (born with this), non specific populations for each type of pathogen etc.
- treat bacteria all the same way
- does not depend on the type of pathogen
Differenciate monocytes and macrophages.
monocytes: mobile leukocyte, phagocytic
when they get to tissues, they are macrophages
What are three important properties of platelets (thrombocytes)?
1- agglutination: sticky
2- adhesiveness: how they stick
3-aggregation: must call upon each other
What are the functions of platelets?
hemostasis and blood coagulation
What is hemostasis?
stoppage of blood flow (coagulation)
What are megakaryocytes and how can platelets arise from that?
they are a giant cell with multiple DNA copies in nucleus.
Fragments of the megakaryocyte break off to form platelets.
What happens during the beginning of hemostasis? (eg. damage to blood vessel walls)
initial damage/trauma to tissue:
- vasospasm =blood vessel will reduce in diameter since vasoconstriction reduces blood loss
- platelet plug formation and with exposure of collagen, releases signal to track areas that needs fixing
- this is a positive feedback as it will attract more platelets
- when enough platelets have been called, feedback cycle will stop.
- intact endothelium will release prostaglandins and nitric oxide which prevents platelets adhesion in normal tissue
- only sticks when called = which is when there is exposure to collagen
What is the hemostasis/blood clotting mechanism?
cascade of events forms a scab
release of cloating factors from both injured tissue cells and sticky platelets at site of injury
series of chemical reactions that result in the formation of thrombin
What is a platelet plug for?
temporary blockage/blood clot
what is thrombin for?
the enzyme that is responsible for converting fibrinogen to fibrin (last part in cascade)
What is the results of fine mesh work?
attracts red blood cells (by trapping them) to form a clot
What happens when there is damage to blood vessel wall?
- vasospasm vasoconstriction to minimize blood loss
- collagen is exposed which attract platelet factors which causes platelets to aggregate and form the loose platelet plug leading to a temporary form of hemostasis and cell growth and repair
- the cell tissue exposed will activate coagulation cascade which is going to form thrombin (enzyme( which converts fibrinogen into fibrin which initiates the formation of the clot
- eventually fibrin gets dissolved (via fibrinolysis) once the damage has been repaired
Why is important to know blood group?
to avoid cross reactions
Identify the blood groups and their corresponding antigens
named according to the antigen present on the RBC type A: antigen A type b: antigen B type ab: antigen A and B on RBC type O: neither antigen A nor B on RBC
What does AB+ mean?
Can receive from everyone
have A and B antigen as well as D/Rh antigen on RBC
What is the explanation behind what is done in the lab to find out the blood type?
take 3 drops of blood
add antibodies (anti A, anti B and anti D drops)
if there is coagulation: for antibody A = you are type A
coagulation for
How can you have Rh in the blood?
not normally present on blood but can only be found in blood once exposed via birth (partner has Rh since it is dominant) or transfusion
What is hemolytic disease of a newborn? What can be done?
When Rh positive blood comes into contact with mother’s blood stream (Rh negative) at the delivery.
If after the first time, the mother is not treated, the anti-Rh (from mother) enters the fetus blood stream and causes agglutination of RBC in the fetus = fatal for second fetus
Use RhoGAM: suppressive drug that limits those antibodies against Rh
Which group of leukocytes is most common in a blood sample from a healthy human?
neutrophils
Which blood component has no nucleus?
RBC & platelets
The percentage of volume occupied by RBCs is called?
hematocrit and PCV
Normal whole blood is __% cells and __% plasma?
45% and 55%
The end product of coagulation cascade is..?
fibrin polymers
Which is not a protein? prostacyclin plasmin plasminogen fibrin
prostacyclin, plasminogen is the inactive form of plasmin
Where are blood cells produces?
bone marrow
What is the term for production of blood cells?
hematopoeisis
A pluripotent hematopoetic stem cell can generate which cell tyoes?
fibroblast
An athelet using EPO (erythropoietin) hopes to increase?
RBC
