Circ System

1. Transport of nutrients, oxygen, hormones
2. Protection of body by leukocytes
3. Regulation: pH, temperature, water content of cells

45%

55%

98-99%

Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils

90%

8%

Albumin: regulates osmotic pressure between blood and tissues

Albumin, Globulin, Fibrinogen

lipid and metal ion transport

clotting factor

8 microns

120 days (4 months)

250 million

4

Globin, the protein part, is broken down into its component amino acids and recycled to blood plasma.
Heme is broken down into Fe and Bilirubin. Fe is bound to Ferritin, Hemosiderin, or Transferrin. Bilirubin is sent to liver, packaged into bile, converted to urobilinogen by intestinal bacteria, converted to stercobilin and eliminated with feces. Some urobilinogen is converted to urobilin and the kidney eliminates it with urine.

Granulocytes: granules that stain inside cytoplasm, irregular nucleus shape with lobes, smaller.

Agranulocytes: no granules in cytoplasm, regular nucleus shape, larger

Neutrophils
Eosinophils
Basophils

Lymphocytes
Monocytes

PMNs = polymorphonuclear leukocytes

1st leukocytes to arrive at infection site, contribute to pus formation

phagocytize antigen antibody complexes, active in fighting parasitic infection, and causing allergic response

release histamine to cause inflammation in response to tissue damage or pathogen invasion

the immune response (specific and nonspecific)

macrophages; actively phagocytic

hemopoiesis

erythropoiesis

hemocytoblasts

red bone marrow

hemocytoblasts make lots of hemoglobin, eject their nucleus (results in depression at center), convert to reticulocytes, and finally mature erythrocytes

in conditions of hypoxia, the kidneys release EPO (erythroprotein), which induces the red bone marrow to produce more erythrocytes

2 million per second

Fe, Vitamin B12, Folic Acid

CSFs- colony stimulating factors

hemocytoblasts -> megakaryoblasts -> megakaryocytes -> platelets (when plasma membrane infolds into cytoplasm and breaks it into fragments)

thrombopoiesis

1. vascular spasm, a constriction of blood vessels
2. platelet plug formation
3. blood clotting

1. platelets adhere to collagen fibers in damaged wall of blood vessel
2. platelets release ADP (to atract other platelets) and serotonin (vascoconstriction) and Thromboxinase A2 (vascoconstriction and attracting other platelets)
3. Platelets accumulate and form a loose mesh (plug)

13; they are named from I to XIII in order of their discovery

gel

Ca(2+) and Vitamin K

1. Factor X (activated via extrinsic or intrinsic pathway) combines with Factor V to form prothrombinase
2. Prothrombinase (with Ca2+) converts prothrombin to thrombin
3. thrombin converts fibrinogen to fibrin
4. fibrin forms long strands that binds platelets together to form a dense mat
5. thrombin also activates Factor XIII that helps fibrin strands cohere to one one another
6. the result is a clot

it's essentially the breakdown of a clot; healthy endothelial tissue secretes Plasminogen Activator that converts Plasminogen to Plasmin; the plasmin breaks down fibrin and the clot dissolves

pericardium

1. outer fibrous: anchors heart to surrounding structures
2. inner serous: there are 2 other layers (outer parietal and inner visceral) that make up this layer, with a serous fluid that provides a slippery surface for the movements of the heart

1. epicardium: visceral layers of serous pericardium
2. myocardium: contracting muscle cells and noncontracting Purkinje fibers
3. endocardium: smooth, inner lining of heart, continuous with inner lining of blood vessels

1. coronary sulcus: marks junction of atria and ventricles

2. anterior interventricular sulcus and posteriour interventricular sulcus: mark junction of ventricles

right atrium, right ventricle, pulmonary trunk, pulmonary arteries, lungs, pulmonary veins, left atrium, left ventricle, aorta, systemic circulation, right atrium

left: bicuspid or mitral valve

right: tricuspid valave

left ventricle; it needs to pump blood throughout the body so it needs to apply more force

papillary muscles are attached to apex end of the ventricles; chordae tendineae are attached papillary muscles and the AV valve; these cords limit the extent to which the AV valves can be closed and thus prevent the AV valve from being pushed too far into the atrium

1. foramen ovale: between interatrial septum
2. ductus aretriosus: between aorta and pulmonary trunk

they are joined with intercalated disks and adjacent cells are connected by desmosomes; they are electrically connected by gap junctions, whihc allow the transmission of an action potential

specialized self excitable cardiac muscle cells that are able to generate an electrical potential wihtout external stimulation by nerve cells

1. SA Node
2. AV Node
3. AV bundle/ Bundle of His
4. Purkinje fibers

located in upper wall of right atrium; it generates an action potential that spreads through both atria through the gap junctions of cardiac muscle fibers

located near the lower region of interatrial septum; delays transmission, allowing atria sufficient time to empty blood into ventricles

receive action potential from AV node and transmit it to ventricles by the way of left and right bundle branches

conduct action potential from interventricular septum, down to the apex, and then upward through the ventricles by the way of their large diameter fibers

atrial depolarization; atria contract and ventricles relax

depolarization of ventricles; ventricles contract and atria relax

repolarization of ventricles; both atria and ventricles relax

1. Isovolumetric ventricular relaxation: ventricles relaxed, both valves (AV and SL) closed
2. Ventricular Filling (rapid filling, then diastasis- slower filling, finally atrial systole - P wave - ventricles completely fill with blood, and this is the EDV - end diastolic volume)
3. Ventricular Systole- QRS complex - ESV - end systolic volume - volume remaining after ventricles contract

"lub-dup"

"lub" = AV valves close
"dup" = Semilunar Valves close

1. volume of blood pumped by one ventricle per contraction
2. number of beats per minute
3. volume of blood pumped by one ventricle per minute (SV * HR)

ratio between maximum and resting cardiac output

1. preload: degree to which cardiac muscle cells are stretched
2. contractility: degree to which muscle cells contract as a result of extrinsic influences
3. afterload: pressure that must be applied by ventricles to force semilunar valves open

the harder that cardiac muscle is stretched, the greater its force of contraction

1. increase contractility of chambers. ex: Ca2+ ions, hormones (epinephrine, thyroxine), drugs (digitalis)
2. decrease contractility. ex: drugs (Ca2+ channel blockers), elevated K+ levels

central cavity/opening of a blood vessel

1. Tunica Intima: inner layer facing the blood, simple squamous epithelium
2. Tunica Media: smooth muscle and elastic fibers
3. Tunica Adventitia: connective tissue

1. Elastic: largest, such as the Aorta and near branches; Tunica Media made up of large amounts of elastic connective tissue
2. Muscular: branch from elastic arteries; distribute blood to rest of the body; smooth muscle in Tunica Media; vascodilation or vascoconstriction; includes most named arteries in the body
3. Arterioles: All 3 tunics present; smooth muscle in Tunica Media, vascoconstrict and vascodilate; smallest arterioles have endothelium surrounded by single layer of smooth muscle

dense, interweaving networks of capillaries that penetrate most tissues

microscopic and thin walled; only the Tunica Media is present; some only have a single layer of endothelium

metarterioles have smooth muscle like arterioles in their tunica media (capillaries don't have a tunica media)

the tail end of metarterioles that connects to the venule and lacks smooth muscle

a ring of smooth muscle in capillaries that regulates blood flow through the capillary

1. continuous capillaries: continuous unbroken walls with cells connected by tight junctions; most capillaries are of this type
2. fenestrated capillaries: continuous walls, but cells have numerous pores (fenestrations) that increase permeability; found in kidneys, small intestine, and other areas where a high transfer rate is required
3. sinusoidal capillaries: large gaps between endothelial cells that permit the passage of blood cells; found in bone marrow, spleen, and liver

1. postcapillary venules: formed by merging capillaries as they leave the capillary bed; very porous, but with scattered smooth muscle fiber in Tunica Media
2. venules: porous enough to allow white blood cells to pass, but most have all three Tunic layers
3. veins: walls with all 3 layers: Tunica intima and tunica media much thinner than similarly sized arteries; few elastic or muscle fibers; well developed tunica adventitia in wall; many have valves, from folds of tunica intima that prevent the backflow of blood

points where arteries merge (since many tissues receive blood from 2 or more arteries); they allow tissues to receive blood even if one of the arteries supplying blood has been blocked

in arteries

120/80 (systole/diastole) (mmHg)

1. movement of muscles squeezes nearby veins, forcing blood to move in one direction, since valves block blood from moving in the opposite direction
2. respiration: inhalation increases pressure in abdominal region and decreases pressure in the thoracic cavity; the pressure difference acts upon the veins passing through the regions => blood flows toward the heart as it moves from regions of higher pressure (abdomen) to regions of lower pressure (chest and right atrium); when pressures are reversed during exhalation, valves prevent backflow

plasma has higher concentrations of proteins

plasma minus blood clotting proteins

liver