Chapter 14 - Blood Flashcards
What is contained in the cardiovascular system?
heart and blood vessels
What is contained in the circulatory system?
heart, blood and blood vessels
What are the 3 main functions of the circulatory system?
transport, protection, regulation
How much blood do most adults have?
4-6 L
What type of tissue is blood?
liquid connective tissue
What is the ECM of blood?
plasma - clear, light yellow
What are the formed elements of blood?
cells and cell fragments - RBC, WBC and platelets
Name all the formed elements in blood:
There are 7 types:
- erythrocytes
- platelets
- neutrophils
- eosinophils
- basophils
- Lymphocytes
- Monocytes
What is hematocrit?
ratio of RBC to whole blood
What are the heaviest cells in blood?
erythrocytes
What is most of blood?
plasma - 55% of whole blood
What is the buffy coat?
- white blood cells and platelets
What is the liquid portion of blood? What is found in this liquid portion?
plasma -
proteins, gases, electrolytes, nitrogenous compounds
What is serum?
plasma with solids removed
How do serum and plasma compare?
serum is plasma without fibrinogens
Name the major categories of plasma proteins:
albumins, globulins, fibrinogen
What structure makes plasma proteins? What is the exception?
liver, immunoglobulins which are produced by plasma cells
Plasma also contains nutrients such as:
glucose, vitamins, fats, cholesterol, phospholipids
Name the gases in plasma:
O2, CO2, nitrogen
Most electrolytes in plasma are:
Na
Nitrogenous compounds in plasma include:
free amino acids from breakdown, nitrogenous wastes (urea), removed by kidneys
Resistance to flow is called:
viscosity
Whole blood is ____ times as viscous as water. Plasma is _____ as viscous as water.
- 5
2. 0
The total molarity in blood that can’t pass through blood vessel wall.
osmolarity
The smallest and most abundant of plasma proteins
albumins
Plasma proteins that provide immune system function
globulins
Plasma proteins that help form blood clots
fibrinogen
Plasma proteins that contribute to viscosity and osmolarity
albumins
If osmolarity is too high what happens to blood pressure?
blood pressure increases
If osmolarity is low what happens to blood pressure?
blood pressure drops and edema occurs in tissues
Production of blood is called? Where does this take place?
hemopoiesis
red bone marrow
What blood cells are produced in red bone marrow?
all seven formed elements
What are pluripotent stem cells? What’s another name for them?
in red marrow, form all elements, also called hemocytoblasts
What are the two principal functions of erythrocytes?
- carry o2 from lungs to cell tissues
- pick up co2 from tissues to lungs
What is the shape of erythrocytes? Why are they shaped this way?
- disc shaped
- increased surface area to volume ratio for gas diffusion
Describe erythrocytes:
no mitochondria, lack of nucleus and DNA as
What forms cytoskeleton proteins of RBC?
spectrin and actin
How do erythrocytes make ATP:
glycolysis (anaerobic fermentation)
1/3 of cytoplasm of RBC is what?
hemoglobin
Name another thing in RBC cytoplasm.
- carbonic anhydrase
- produces carbonic acid which dissociates into H+ and bicarbonate
What makes up hemoglobin molecules:
- 4 proteins globins - two alpha and two beta chains binds co2
- 4 heme groups - bind oxygen at ferrous ion core
What indicates amount of oxygen blood can carry?
RBC count and hemoglobin concentration
Why is hematocrit lower in women?
- menstration, inversely proportional to body fat, androgens stimulate RBC production
What is the average lifespan of a RBC? How long does RBC development take?
120 days
Describe the development of RBC
- Hemocytoblast (pluripotent stem cell)
- Erythrocyte CFU (first committed)
- Erythroblast - produce hemoglobin
- Reticulocyte - fine network of endoplasmic reticulum - degraded nucleus
- Erythrocyte -
What is the first committed cell in RBC development? What does this cell have?
erythrocyte colony-forming unit, has EPO receptors from kidneys
What cell of RBC development produces hemoglobin
erythroblast
What cell has nucleus fragments
reticulocytes
What is the first cell to enter blood?
reticulocyte
Drop in RBC leads to:
kidney hypoxemia, kidney produces EPO and RB increases
Name some stimuli for increasing RBC production:
- low O2 levels, high altitude, increase in exercise, lung diseases
RBC are degraded/lyses by:
liver and speen
How is a RBC broken down by the spleen?
separate heme from globins, globins become amino acids, iron and heme separated. Heme converted to biliverdin then bilirubin (yellow).
then small intestine and becomes brown urobilinogen
When iron is recycled where is it stored?
liver as ferritin
What is the disorder called of too many RBC:
polycythemia
What are the types of polycythemia:
primary - cancer
secondary - dehydration, lung disease, high altitude
What are the dangers of polycythemia:
increased blood volume, pressure and viscosity
What is low RBC or low hemoglobin?
anemia
What type of anemia involves lack of iron?
iron-deficiency anemia
What type of anemia involves lack of B12
pernicious anemia
What type of anemia involves red bone marrow destroyed
aplastic anemia
What type of anemia involves RBC destroyed too early:
hemolytic anemia
What are the consequences of anemia?
- tissue hypoxia and necrosis
- blood osmolarity is reduced leading to edema in tissues
- low viscosity heart races and pressure drops
What happens in sickle-cell disease?
hemoglobin defect that causes 6th amino acid mutation and Hbs dont bind oxygen well, RBC become rigid sticky and pointed
What determines blood type?
antigens found on RBC surface called agglutinogens, develop an immune response
Blood also contains antibodies called:
gamma and immunoglobulins secreted by plasma cells - agglutinins
What is it called when antigens bind to antibodies? What happens in the blood?
agglutination, clumping of RBC
What are the types of antigens?
A&B
What are the types of antibodies?
anti-A and anti-B
What does a person with type A blood have? What about type B?
- type A has A antigens and antibody B
- type B has B antigens and antibody A
What is the most common blood type?
type O, no antigens
What is the rarest blood type?
AB, has both A and B antigens but no antibodies
Why is transfusion reaction dangerous?
blood clumps and can clog small blood vessels, hemoglobin released and leads to kidney failure
What blood lacks antigens?
Type O, but has both antibodies
Universal recipient is:
type AB, no plasma antibodies
What agglutinogens discovered in monkeys?
Rh
What is the most reactive Rh?
Rh D, if have D then positive, if lack than negative
What happens if Rh- individual is exposed to Rh+ blood?
develop anti-D antibodies
How can Rh be dangerous to fetus? And how do you prevent this?
Hemolytic disease of the newborn. Rh- woman with anti-D antibodies with a second Rh+ child, the anti-D antibodies can cross the placenta and hurt the child- lead to anemia and toxic brain syndrome. Give pregnant women RhoGAM which binds agglutinogens so she will not form anti-D antibodies
What is the least abundant formed element in blood?
white blood cells
Describe features of white blood cells in general? Nucleus?
They have formed nuclei, retain organelles for protein synthesis
What are the categories of white blood cells or leukocytes?
- granulocytes: neutrophils, eosinophils, basophils
- agranulocytes: lymphocytes, monocytes
Describe neutrophils:
- 3-5 lobed nucelus
- phagocytize bacteria
Describe Eosinophils:
- bilobed orange nucleus
- phagocytize antigens/antibodies and destroy large parasites
What is the most abundant WBC
neutrophils
Describe basophils:
large violet granules
s-shaped nucleus
secrete histamine and heparin
Describe lymphocytes:
- uniform dark violet round nucleus
- coordinate action of other cells
- immune memory, can last for years for immunity
- developed in thymus
- destroy cells
Describe monocytes:
- largest WBC
- horseshoe shaped nucleus
- leave bloodstream and become macrophages
- antigen presenting cells
Myeloblasts form what cells:
granuloctyes
Monoblasts form:
monocytes
Lymphoblasts give rise to:
lymphoctyes
Where do T-lymphocytes complete development?
thymus
Low WBC count is called:
leukopenia, caused by radiation, poisons, infectious diseases
High WBC count:
Leukocytosis - allergy, disease, infection
Cancer of hemopoietic tissues leading to high number of WBC
leukemia
CBC consists of:
hematocrit, hemoglobin concentration, RBC size, total RBC, reticulocytes, differential WBC count,
The cessation of bleeding is called:
hemostasis
Platelets are small fragments that form from:
megakaryocytes
What are the 3 hemostatic mechanisms?
- vascular spasm
- platelet plug
- blood clotting
What do platelets do?
form platelet plugs and secrete procoagulants, secrete growth factors and attract WBC to the area
What is the formation of platelets called?
thrombopoiesis
How are Megakaryocytes formed?
stem cells that develop receptors for thrombopoietin
Describe Megakaryoctyes
replicate DNA but do not divide, therefore form huge cells with mulitlobed nucleus
and long cytoplasmic tendrils called proplatelets that protrude into blood sinusoids. circulate freely for 10 days, stored in spleen
Where do Megakaryoctyes live?
bone marrow adjacent to blood sinusoids
What happens in vascular spasm?
prompt constriction of broken vessel
What can cause vascular spasm?
- pain receptors
- smooth muscle injury
- platelets release serotonin (vasoconstrictor)
What are some effects of vascular spasms? Compare the timeline of pain receptor mediated vs. smooth muscle injury mediated:
pain receptors - short duration
Smooth muscle injury - longer duration
Do all 3 hemostasis pathways involve platelets?
YES
Describe platelet plug formation:
broken vessel exposes collagen, platelet pseudopods stick to damaged vessel and other platelets forming a plug
- platelets then degranulate releasing various vasoconstrictive substances
Are platelets involved in positive or negative feedback cycle? And when does the cycle stop?
positive, stops when break in vessel is sealed
Describe clotting/coagulation:
most effective defense against bleeding,
- fibrinogen turns into fibrin threads to form framework of a clot
- liver produces clotting factors that activate in a reaction cascade
Coagulation involves a clotting pathway. Describe the steps of this pathway:
factor X –> prothrombin activator —> thrombin –> fibrin
-positive feedback
How long for clot retraction to occur?
30 minutes
What happens after a clot to heal the tissue?
platelet-derived growth factor secretes by platelets and endothelial cells which is a mitotic stimulant for fibroblasts and smooth muscle to multiply and repair the tissue/vessel
What is the dissolution of a clot?
fibrinolysis (fibrin in the clot material and lysis mean break up)
What is hemophilia?
hereditary diseases with deficiencies of blood clotting factors
What is hemophilia A? What is hemophilia B? C?
missing factor VIII
missing factor IX
missing factor XI
How do you treat hemophilia?
inject plasma or clotting factors. VIII can be produced by transgenic bacteria
What is a hematoma?
masses of clots, too much clotting
What is abnormal clotting called?
thrombosis
What is another name for a clot?
thrombus
What is a pulmonary embolism?
clot that breaks free from vein and travels to lungs
What is infarction?
tissue death, clot breaks blood supply to organ
What are some ways to prevent clots?
Vitamin K antagonist since vitamin K is required to make clotting factors - coumarin, warfarin, also can use aspirin (thromboxane)
What are some natural anticoagulants?
Heparin (from basophils) and mast cells as well as antithrombin which deactivates thrombin before it can act on fibrinogen to make fibrin.
