systems exam 2 content

3 functions of blood

transport, regulation, protection

what does the blood for transportation

o2 and nutrients to body cells, metabolic waste to lungs and kidneys

how does blood do regulation

• maintaining body temp by absorbing and distributing heat

• maintaining normal pH

• maintaining adequate fluid volume in circulatory system

how does the blood protect 

• prevents blood loss- platelets initiate clot formation 

• preventing infection: antibodies, white blood cells 

why do we give patients fluids when they are losing blood

bc 90% or blood is water, so fluids will replace that lost water

what are the formed elements 

rbcs, wbcs, thrombocytes(platelets)

what is plasma made up of 

90% water, nutrient, gases, hormones, wastes, protein, dissolved solutes 

what is blood made of

red blood cells, plasma, Buffy coat

what is the Buffy coat in blood

composed of white blood cells and platelets

erythrocytes

red blood cells, contain hemoglobin

what do erythrocytes lack 

a nuclei,(so no DNA) and organelles 

hemoglobin

protein in red blood cells to which oxygen and carbon dioxide reversibly combine, contain iron in the center

examples of blood vessels

arterties, arterioles, capillaries, venues, and veins

arteries

carry oxygenated blood away form heart

veins 

carry deoxygenated blood to heart

what are the circuits of blood flow

systemic and pulmonary

vessels involved in pulmonary circuit

pulmonary arteries, veins, capillaries

pulmonary circulation

carries oxygen-poor blood then returns oxygen rich blood 

systemic circulation

carries oxygen rich blood then returns oxygen poor blood

vessels involved in systemic circuit 

aorta, systemic arteries and capillaries, systemic veins, superior and inferior vena cava 

pressure

force exerted by blood, comes of the heart and into aorta

what is blood directional flow with pressure

flows from high to low pressure

what is the relationship between a vessel and pressure 

the lower the pressure, the further away the vessel is 

flow

volume of blood moved per unit time

resistance

how difficult it is for blood to flow between 2 points at any given pressure difference

factors that determine resistance

blood viscosity, total blood vessel length, blood vessel radius 

blood viscosity

friction btw molecules of a flowing fluid, affected by water volume and number of red blood cells

what does blood viscosity do to resistance

decerases resistance, makes blood flow more easily

does blood vessel length remain constant

yes

what decreases resistance when it comes to blood vessels

dilated vessels

what increases resistance when it comes to blood vessels 

constricted vessels 

what is the most important determinant of changes in resistance and why

blood vessel radius bc it does not remain constant

hematopoiesis

formation of all blood cells, occurs in red bone marrow

hematopoietic stem cells 

also known as hemocytoblasts, stem cell that gives rise to all formed elements 

do committed cells change

no

erythropoiesis

process of formation of RBC’s

reticulocytes

immature RBC’s, indicates the level/ rate of erythropoiesis also mark when blood transfusion is done

tissue hypoxia

too few RBCs

too many RBCs causes what? 

increase in blood viscosity 

dietary requirements for erthropoiesis

iron, vitamin B12 and folic acid

where is 65% of iron found

hemoglobin

where is the rest of iron found

liver, spleen, bone marrow

why does free iron bind to protein 

bc it is toxic 

what stores iron in cells

ferritin and hemosiderin

transferrin

protein that binds and transport iron in the bloodstream

what are vitamin B12 and folic acid necessary for

DNA synthesis for developing RBC’s

erythropoietin

hormone that stimulates formation of rbc, released by kidneys in response to hypoxia

causes of hypoxia

• decreased rbc numbers( hemorrhage or increased destruction)

• insufficient hemoglobin per rbc ( ex. iron deficiency)

• reduced availability of O2

what can inhibit epo production 

too many erythrocytes or high oxygen levels in blood 

what does epo do to erythrocytes

causes erythrocytes to mature faster

what in males enhances epo production and what does it lead to

testosterone, leads to higher rbc counts in males

what does artificial epo do 

increases hematocrit, which allows athletes to increase stamina and performance 

dangerous consequences of epo

it can increase hemotrit form 45%, leads to clotting, stroke or heart failure

how are rbc broken down

heme, iron and globin separate

where does iron go in rbc breakdown

binds to ferratin and hemosiderin and stored for reuse

bilirubin

yellow pigment heme is degraded to

what does the liver do with bilirubin

secretes bilirubin (in bile) into intestines, where degraded into urobilinogen

what happens to globin 

metabolized into amino acids and released into circulation 

anemia 

low o2 carrying capacity that is too low to support normal metabolism; symptoms: fatigue, pallor, chills, dyspnea 

iron-deficiency anemia

impaired absorption of iron, affect menstruating women

pernicious anemia

autoimmune disease destroys the stomach mucosa, produces intrinsic factors (via B12 absorption) or low dietary B12; tx: nasal gel or vitamin B12 injections

aplastic anemia

bone marrow failure due to toxic drugs or cancer, all formed elects are going to be low, clotting and immunity defects tx: bine marrow transfusion

renal anemia

inadequate secretion of EPO in kidney disease , tx: synthetic epo

hemolytic anemia

excessive destruction of erythrocytes, premature lysis of rbc’s

polycythemia

abnormal excess of rbc, increases blood viscosity

leukocytes 

white blood cells, make up <1% of total blood volume, function in defense against disease 

leukocytosis

Wbc count over 11,000ul, increases is a normal response to inffection

major categories of leukocytes

granulocytes and agranulocytes

granulocytes

contain cytoplasmic granules (neutrophils, eosinophils, basophils)

agranulocytes 

Agranulocytes: no cytoplasmic granules (lymphocytes, monocytes)

increase in neutrophil indicates

bacterial infection or inflammation

increase in lymphocytes indicates

viral infection, have b cells to produce antibodies and T cells that fight virus infected cells

increases in eosinophil indicates 

parasitic infection or allergic reaction or asthma 

what produces histamine

basophils

what do all leukocytes originate from

hemocytoblast stem cell

lymphoid stem cells

produce lymphocytes

myeloid stem cells

produce all other elements

leukopenia

abnormally low Wbc count, • Can be drug induced, particularly by anticancer drugs or glucocorticoids

leukemias 

Cancerous condition involving overproduction of abnormal WBCs
• Immature, nonfunctional WBCs flood bloodstream

Cancerous cells fill red bone marrow, crowding out other cell lines
• Leads to anemia and bleeding

death caused from internal hemorrhage or overwhelming infections

tx: irradiation, anitleukemic drugs, stem cell transplant 

Thrombocytopenia

deficient number of circulating platelets,
Platelet count <50,000/μl is diagnostic
• Treatment: transfusion of concentrated platelets

Petechiae(spots on the foot) appear as a result of spontaneous,
widespread hemorrhage

Impaired liver function
• Inability to synthesize procoagulants (clotting factors)
• Causes include vitamin K deficiency, hepatitis, or cirrhosis
• Liver disease can also prevent liver from producing bile, which is needed to absorb fat and vitamin K

Thrombus

a stationary clot, May block circulation, leading to tissue death

Emboli

moving clot, Risk factors: atherosclerosis, slowly flowing blood or blood stasis from immobility

pathway of blood

SVC + IVC → RA → Tricuspid valve → RV → Pulmonary valve → Pulmonary
trunk → R/L Pulmonary artery → Lungs → R/L Pulmonary veins →LA →
Mitral/Bicuspid valve → LV → Aorta → to the rest of the body  

what are the largest veins in the body

sva and ivc

what chambers receive blood

atria

what do valves prevent

backflow

what vein is an excerption that doesn’t carry 02 poor blood

pulmonary vein

foreman ovale

connect between ra and la in fetus, turns into fossa ovallis after birth

what side of the heart is the systemic circuit pump

left side

what side of the heart pumps blood to the lungs

right side

what are cardiac muscle cells called

myocytes

types of myocytes

contractile and pacemaker cells

contractile cells

responsible for contraction

pacemaker cells 

noncontractile cells that depolarize; Do not need nervous system stimulation,

how does the heart contract

as a unit, all cardiomyocytes contract as a unit, or none contract

what does the contraction of all cardiac monocytes ensure

effective pumping action

coordinated heartbeat is a function of

presence of gap junctions

intrinsic cardiac conduction system

• Network of noncontractile (autorhythmic) cells
  • Initiate & distribute impulses to coordinate depolarization and contraction of heart

what is required for the heart to contract

depolarization

3 parts of action potential initiated by pacemaker cells 

1. pacemaker potential: K+ channels are closed, but Na+ channel are open, causing interior to become more positive 

2. depolarization: pacemaker potential reaches threshold, ca2+ channels open (around 40mV), allowing huge influx of ca2+, leading to rising phase of action potential 

3. repolarization: ca2+ channel inactivate, k+ channels open, allowing efflux of K+, and cell becomes more negative