Circulatory System part II (Blood and Blood Vessels)

hematopoesis

formation, development, and differentiation of blood cells; occurs in bone marrow and completed in lymphoid tissue (only some types of blood cells)

hematopoetic stem cells

multipotent (can only become one types of blood cells), unspecialized cells found in bone marrow and lymphatic structures, mature into different types of blood cells

red blood cells

erythrocytes, lack nucleus and organelles, contain pigment hemoglobin, 2.5 million produces and broken down every second

hemoglobin

found in RBCs, binds to oxygen for transport 

• contains 4 polypeptide chains (globins) which each contain a heme (iron containing) group 

• carry 4 oxygen per molecule → 1 RBC can carry 1 billion oxygen

erythropoetin (EPO)

Hormone produced by the kidneys that stimulates increased rate of RBC production from bone marrow

Erythropoeisis

the production of RBCs; development begins in bone marrow and completes final stages in bloodstream

hypoxia

cellular oxygen deficiency; not enough oxygen in the blood results in increased rate of erythropoiesis (due to high altitude, anemia, circulatory problems)

• stimulates kidneys to produce erythropoietin

hematology

study of blood and its disorders

hematocrit

% of blood volume occupied by RBCs; used as a diagnostic tool to determine anemias

anemia

abnormally low RBC hematocrit/amount

polycythemia

abnormally high RBC hematocrit/amount

White Blood Cells

• leukocytes

• leave bloodstream and collect at points of pathogenic invasion or tissue damage

• combat pathogens through phagocytosis or production of antibodies

Pathogens

disease cussing against (ex. bacteria or viruses)

Phagocytosis

ingesting/engulfing pathogens

Antibody

proteins that attach to specific pathogens and destroy them

Leukocytosis

increase in # of WBCs; normal response to microbes/infection (ex. due to cancers such as lukemias)

Leukopenia

abnormally low # of WBCs (ex due to exposure ot radiation)

Platelets

thrombocytes (cell fragments)

• aid, along with specific blood proteins, in blood clotting where blood vessels have been damaged

hemostasis

stoppage of bleeding

thromboplastin

tissue factor 

• chemical released by damaged cells 

• combines with blood calcium to produce prothrombinase

prothrombinase

protein which along with calcium converts prothrombin into the enzyme thrombin

prothrombin

plasma protein produced by liver

thrombin

protein which catalyzes a reaction that converts fibrinogen into fibrin

fibrinogen

soluble plasma protein produced by the liver which forms mesh around blood clots

fibrin

forms the thread of the clot; formed elements of the blood are trapped

fibrinolysis

breakdown of a clot as a damaged blood vessel is repaired, during clot formation the plasma protein plasminogen is incorporated into the clot, the newly formed healthy endothelial tissue secretes plasminogen activator that converts plasminogen into plasmin (fibrinolysin) which breaks down fibrin leading to the dissolution of the clot

thrombus

clot attached to a vessel wall

embolus

free-floating clot; may lead to heart attack or stroke

anticoagulants

group of substances used as blood thinners 

• inhibit blood clotting

• ex. heparin

coagulation

formation of a blood clot

Aorta

delivers oxygenated blood from left ventricle to systemic circulation

pulmonary artery

delivers deoxygenated blood to the lungs from the right side of the heart

carotid arteries

delivers oxygenated blood to the brain, face and neck. Located laterally on both sides of the neck.

subclavian arteries

delivers oxygenated blood to the arms, shoulders, head, and neck. Located below the clavicle (collarbone).

Hepatic Artery

Delivers oxygenated blood to the liver (as well as other abdominal organs). Branches from celiac trunk and is found in upper right abdomen.

Mesenteric Arteries

Delivers oxygenated blood to the GI tract organs such as intestines, stomach and spleen. Branches from the aorta and is found between the celiac and renal arteries.

Renal artery

delivers oxygenated blood to the kidneys, branches from the abdominal aorta and located in the retroperitoneum

iliac artery

delivers oxygenated blood to the lower body including the pelvic region, and legs. Originates from the aorta and ends at the femoral arteries

jugular veins

transports deoxygenated blood away from the head, face and neck. 4 veins (2 found deeper the neck and 2 found more superficially on both sides of the neck). Drains into the subclavian vein.

Subclavian veins

transports deoxygenated blood from the arms and shoulder. Located underneath the clavicle. Begins at ribs and empties into the brachiocephalic vein

pulmonary veins

transports oxygenated blood away from the lungs to the left atrium of the heart

superior vena cava

transports deoxygenated blood from the heart, neck, arms, and chest to the right atrium of the heart. Runs vertically down the thorax and mediastinum.

Inferior Vena Cava

Transports deoxygenated blood from the lower body (including legs, abdomen, and pelvic organs) to the right atrium of the heart. 

Hepatic Vein

Transports deoxygenated blood away from the liver into the inferior vena cava.Found on the posterior side of the liver.

Hepatic Portal Vein

Transports deoxygenated blood away from GI tract organs to the liver where the blood is filtered and processed by the liver. The blood the joins the inferior vena cava. Located in upper right quadrant of the abdomen (form behind pancreas to hilum of liver).

Renal Veins

Transports deoxygenated blood from the kidneys to the inferior vena cava. Begins at the renal hilum. one vein for each kidney, left vein is longer because it must cross the body to reach inferior vena cava.

iliac veins

transports deoxygenated blood from the legs and pelvis to the inferior vena cava. Located in the pelvis and lower abdomen. 

albumin

protein founding blood plasma which maintains osmotic pressure (prevents water from leaking out of blood cells)

gamma globulins (antibodies)

globular protein found in blood plasma. Attacks foreign proteins by linking to antigen and inactivating it (shape dependent). Protein is produced by certain WBCs (B cells).

hypertension

chronic high blood pressure

poor diet, sedentary lifestyle, family history, weight, age, stress

causes of hypertension

spyhgmomanometer

blood pressure cuff

direct relationship

effect of heart rate/stroke volume on blood pressure

direct relationship

effect of blood volume on blood pressure

direct relationship

effect of blood viscosity on blood pressure

inverse relationship

effect of diameter of blood vessels

vasoconstriction

smooth muscles contract narrowing blood vessels → increases blood pressure

vasodilation

smooth muscles relax and enlarge diameter of blood vessels → decreases blood pressure

systolic blood pressure

force exerted by blood on walls of arteries during periods of ventricular contraction

diastolic blood pressure

force exerted by blood on walls of arteries during periods of ventricular relaxation

120/80

normal blood pressure (systolic/diastolic) units = mmHg