AP II

　




Fist sized, hollow, cone-shaped, 250 to 350 grams

　




Placed in the thoracic medial cavity (mediastinum)

　




Extends obliquely, tilted left, for 12 to 14 cm from the second rib to the fifth intercostal space

　




It rests on the superior surface of the diaphragm and

Lies anterior to the vertebral column and posterior to the sternum.

The lungs are on the lateral side

　




It's Tip (called apex), is the point of maximal intensity

　




The heart wall is a double-walled sac called

The loosely fitting superficial part of the sac is call fibrous pericadium: Is tough, dense connective tissue layer designed to do three things

The loosely fitting superficial part of the sac is called

The heart wall composed of three layers

The superficial epicardium is the visceral layer of what? Often filtrated with fat, especially in older people.

　



The heart wall is rich in blood supply, and made up of what kind of tissue?

　




the heart wall middle layer, has cardiac muscle, involved in contraction, form crisscrossing tissue fibers and arranged in spiral or circular bundles

　




Located in the heart wall is a sheet of squamous epithelium on a thin connective tissue layer.

　

　






Located on the inner myocardial surface of the heart wall





Located on the inner myocardial surface
•covers the fibrous skeleton of the valves.

The layer lines the heart chambers

　






Part of the heart wall this layer covers the fibrous skeleton of the valves.

How many chambers of the heart

What are the 4 chambers of the heart

　




This separates the atria longitudinally L and R

　



This separates the ventricles.

　




This ventricle forms most of the anterior surface

　




This ventricle dominates the inferoposterior aspect of the heart and forms the heart apex.

Otherwise known as the Receiving Chambers

　




it's Left and Right chambers, are small and thin-walled

　




In this chamber is pushes blood "downstairs" into the ventricles, low pressure

　




Blood enters the right atrium via these three veins

　






This vein returns blood to the heart from the body regions superior to the diaphragm

　






The vein returns blood to the heart from body areas below the diaphragm

　






This vein collects blood from the myocardium.

How many pulmonary veins enter the left atrium, transporting blood from the lungs back to the heart

What veins enter the left atrium? transporting blood from the lungs back to the heart

Using the pulmonary veins blood enter the left atriumfrom where?

Also know as the Discharging Chambers

　




make up most of the volume of the heart

　




It's internal walls have irregular ridges of muscle trabeculae carneae "crossbars of flesh", massive

　




Cone-like papillary muscles play a role in valve function, project into this cavity

　




The Left ventricle contracts to propel blood out of the heart into circulation via the?

this is the largetst artery

Which chamber pumps blood into the pulmonary trunk?

The right ventricle pumps blood into this; which routes the blood to the lungs where gas exchange occurs.

　




The R ventricle pumps blood into the pulmonary trunk, to the lungs for this reason?

　




The blood vessels that carry blood to and from the lungs for gas exchange is called what circuit

　




The blood vessels that carry blood supply to and from all body tissues is part of what circuit.

　




The functional blood supply to the myocardium; is the shortest circulation in the body

　




Function of the left side of the heart

　




This pathway of Oxygenated blood from the lungs to the LA to LV, pumped into the aorta

　




From the Aorta to smaller systemic arteries to the body tissues, where gases and nutrients are exchanged across the capillary walls support what pathway

　




Blood loaded with CO2 and depleted of O2, returns through the systemic veins to the R side of the heart

　




Through the superior and inferior venae cavae, the RA receives blood from what circuit

　




smaller systemic arteries carry to the body tissues, where gases and nutrients are exchanged across the capillary walls. As blood loaded with CO2 and depleted of O2, returns through the systemic veins to the R side of the heart, entering the RA through the superior and inferior venae cavae. This happens how often?

　




Function of the right side of the heart

Pulmonary Circulation

　




Blood returning from the body is O2 poor and CO2 rich in what circuit

　




From RA to RV, then to lungs the blood uses this

　




In the lungs, the blood unloads CO2 and picks up O2 during this circulation

　




The freshly oxygenated blood is carried by the pulmonary veins back to the left side of the heart during this circulation

True or false: the Pulmonary circulation pumps handles more blood volume than the Systemic Circulation
True False

　




Via the RV, this is a short, low-pressure circulation

　




via the LV, the blood takes a long pathway, encounters 5x friction, or resistance to blood flow in what circuit

　




The walls of the LV (which are nearly circular) are how many time as thick as compared to the wall of the RV

　




Which ventricle generates much more pressure than the other and is a far more powerful pump

　




The arterial supply of the coronary circulation is by which arteries, both arising from the base of the aorta and encircling the heart in the coronary sulcus

　




The LCA toward the L side of the heart and then divides into its major branches:

　






follows the anterior interventricular sulcus and supplies blood to the interventricular septum and anterior walls of both ventricles

　






Supplies blood to the left atrium and the posterior walls of the left ventricle.

　




The RCA courses to the right side of the heart, where it also divides into two branches

　






the artery that supplies blood to myocardium of the lateral right side of the heart

　






this artery runs to the heart apex and supplies the posterior ventricular walls

　






Near the apex, this artery merges (anastomoses) with the anterior interventricular artery

　






Together these branches of the RCA supply the right atrium and nearly all the right ventricle with blood

Blood flows in how many directions through the heart.

how many valves in the heart

　




There are 4 valves that open and close in response to what on their two sides?

Two of the four vales are located where?

The two valves at the Atrial-ventricular junction are designed to do what?

the right AV valve (Atrial-ventricular) has three flexible cusps (flaps of endocardium reinforced by connective tissue cores) the valve is called what?

The left AV valve (atrioventricular), with two flaps, is called

　




Two semilunar valves (half-moon)

The aortic and the The pulmonary

　






The valve that guards the bases of the aorta and prevent backflow into LV.

　






This valve guards the bases of pulmonary artery and prevent backflow into RV

　




What is the role of Cardiac skeletal muscles?

　




Large mitochondria account for how much of the volume of cardiac cells (only 2% in skeletal muscle)

What gives cardiac cells a high resistance to fatigue.

　




Cardiac muscle cells are self-excitableand can initiate their own what

Cardiac muscle cells initiate their own depolarization in a spontaneous and rhythmic way called what

　




In cardiac muscle, the heart either contracts as a unit or what happens?

　




The ability of cardiac muscle to depolarize and contract is

The depolarization wave travels across the heart from cell to cell via ion passage throught what type junction

　




An impulse (electrical excitation) located in the RA wall, excites ~ 75 times every minute

　




Sinoatrial node (SA) sets the pace for the heart (pacemaker) and its rhythm is called?

Sinus rhythm determines what

　




From the SA node, the depolarization wave spreads via atrial gap junctions to the what?

　




From the AV node, the impulse sweeps to this in the superior part of the interventricular septum (leads into the R and Left bundle branches)-apex.

　




impulse passes through long strands of barrel-shaped cells, penetrate into the heart apex, and then turn superiorly into the ventricular walls.

　




is a tracing of a single action potential of heart activity

　




ECG has three distinguishable waves or deflections, what are they

　






This wave lasts 0.08s, movement of the depolarization wave from the SA node through the atria

　






0.1 s after the P wave begins, what contracts?

　






This results from ventricular depolarization and precedes ventricular contraction, lasts 0.08 s.

　






This is caused by ventricular repolarization and lasts 0.16 s.

　






Why is theT wave more spread out and has a lower amplitude

　






What is the time called (about 0.16 s) from the beginning of atrial excitation to the beginning of ventricular excitation

　




1 contraction (systole)and 1 relaxation (diastole)

The contraction and relaxation periods during a cardiac cycle is called

　




At what point does the atria contract, compress the blood, rise in atrial pressure, pushes blood from the atria to the ventricles.

　




When the ventricles are in the last part of their diastole and have the maximum volume of blood they will contain in the cycle, a volume called

　




When the atria relax and the ventricles depolarize

　




Contraction of the ventricles -closing the AV valves.

　




for a split second, the ventricles are completely closed chambers and blood volume in the chambers remains constant

　




During this ventricular ejection phase, the aortic pressure is

　




brief phase following the T wave -the ventricles relax.

When the ventricles relax during early diastole the blood remaining in their chambers is referred to as

Pressures: Systemic Aortic or Arterial

Systolic –120 mm Hg;Diastolic: 80 mm Hg

　




Pressure: Pulmonary arterial

Systolic -24 mm Hg;Diastolic: 8 mm Hg

True or False do the two sides of the heart eject the same blood volume with each heartbeat
True False

　




defined as the volume of blood pumped out by one ventricle with each beat, is correlated with the force of ventricular contraction

　




is the amount of blood pumped out by each ventricle in 1 minute.
? = HR x SV

what is the Normal resting values for the heart beat and the stroke volume.

True or False: the SV tends not to be relatively constant
True False

The increase of the heart rate is also called

The decrease of the heart rate is also known as

　




imbalances of this pose real dangers to the heart

　




enhances heart rate and contractility.

　




increases metabolic rate and body heat production.

　






When released in large quantities, this causes a slower but more sustained increase in heart rate than that caused by epinephrine