Cardiovascular System (Part I. Blood)

3 general functions of blood

transportation, regulation, protection

what does blood transport

gases, nutrients, hormones, waste products

what does blood regulate

pH, body temperature, osmotic pressure

what does blood protect

clotting, white blood cells, proteins

phrase for blood

liquid connective tissue

formed elements in blood

red blood cells, white blood cells, platelets

other names for red blood cells

RBCs, erthrocytes

other names for white blood cells

WBCs, leukocytes

other name for platelets

thrombocytes

blood plasma is made of

90% water, 10% solutes (primarily proteins)

solutes in blood plasma

albumins, clotting factors, antibodies, globulins

electrolytes, nutrients, enzymes, hormones, gases and waste products

blood is made of

red blood cells (45%), white blood cells, platelets, and plasma (55%)

red blood cells/erythocytes contain

hemoglobin

hemoglobin

oxygen-carrying protein

red blood cell shape

bioconcave disc which increases surface area

rbc plasma membrane

strong, flexible

rbcs lack

nucleus, mitochondria

surface of RBCs contain

agglutinogens

agglutinogens

genetically determined assortment of antigens

blood groups are based on the

presence or absence of various antigens

number of blood groups and antigens

at least 24 blood groups and more than 100 antigens

most important blood group and antigen classifications

ABO, Rh

antigens (Ag)

proteins that trigger immune responses

antibodies (Ab)

formed proteins of our immune response

Ab-Ag reactions protect us from

pathogens

Ab-Ag reactions can trigger

unwanted transfusion reactions

Types of ABO classifications

A, B, AB, O blood

A blood

carry the A antigen (and anti-B antibodies)

B blood

carry the B antigen (and anti-A antibodies)

AB blood

carry both A and B antigens (no antibodies)

O blood

carry both A and B antigens (no antibodies)

for transfusion compatibility

donor and recipient must be compatible

if a person with Type A blood, receives transfusion of Type B

Anti-B antibodies in recipients Type A blood will attack the RBCs of donated blood (B antigen)

Also – Anti-A in the B blood will attack the A of the recipient (but volumes are much less)

aggutination

occurs when RBCs stick together; happens when antibodies bind to incompatible antigens on RBC surfaces

hemolysis

occurs when RBCs rupture (break open); releases hemoglobin into the surrounding plasma; can happen following an incompatible blood transfusion.

agglutination and hemolysis can cause

kidney damage

Rh factor

an antigen (Rh D) found on the surface of red blood cells

Rh+ means

Rh D antigen is present on rbcs

Rh- means

Rh D antigen is absent on rbcs

A+ and AB+ indicate

the ABO blood type plus the presence of the Rh D antigen

Rh incompatibility occurs during pregnancy when

an Rh- mother carries an Rh+ fetus

during the first Rh+ pregnancy

fetal Rh+ blood may enter the mother’s blood, triggering anti-Rh antibodies

what happens in pregnancies after Rh sensitization

mother retains immune memory and can produce anti-Rh antibodies

why can a later Rh+ pregnancy be dangerous

maternal antibodies can cross the placenta and destroy fetal RBCs

hemolytic disease of newborn

destruction of fetal or newborn RBCs by maternal antibodies

how to prevent Rh-related hemolytic disease

anti-D immunoglobulin (RhoGAM) prevents Rh sensitization in eligible mothers

WBCs are part of our

circulatory and immune system

WBCs have

nuclei

WBCs do not contain

hemoglobin

WBC cell classifications

granular, agranular

granular leukoctyes

neutrophils, eosinophils, basophils

granular leukocytes structure

have dots

agranular leukocytes

lymphocytes, monocytes

general function of WBCs

immune response

WBCs non-specific immune responses (fast, general defense)

neutrophils, monoctyes, phagocytosis (engulf virus)

WBCs specific immune responses (adaptive immunity)

B and T lymphocytes (develop memory of previous infections)

WBCs allergic responses

basophils (histamine release)

platelets give us

protection when their is damage to our circulatory system (you are bleeding), hemostasis

platelet cell structure

disc-shaped with many veiscles, contain clot-forming chemicals, but no nucleus

platelet life span

5-9 days (short)

hemostasis

the body's normal physiological process that stops bleeding and prevents excessive blood loss after a blood vessel is injured.

steps of hemostasis

1. platelet plug

2. coagulation (if needed)

coagulation

blood clotting

platelet plug formation steps

damaged endothelium, platelet adhesion, secretion of inflammatory mediators, platelet aggregation

if more than platelet plug is needed…

a clot is formed

formation of fibrin strands (soluble fibrinogen → insoluble fibrin)

blood clotting factors

proteins (that get activated) and signal for coagulation cascade

blood clotting intrinsic pathway

within the damaged vessels, activation of blood-clotting factors

blood clotting extrinsic pathway

outside of the CV system (in the tissues); tissue factors help with this process

blood clotting is a

cascade effect

blood clotting pathway steps

1. inflammatory proteins (activation of blood clotting factors)

2. transform Prothrombin (II) to Thrombin (IIa)

3. transform Fibrinogen (I) (soluble) to Fibrin (Ia) (insoluble) 

thromoembolic disorders

too much blood clotting

hemophilia

missing clotting factors (factor VIII)

plasma

draw blood

collection tube is lined with anticoagulant

clotting factors (unactivated) remain in the plasma

serum

draw blood

leave blood without anticoagulant

clotting factors are activated, form clot

serum is plasma with no

clotting factors