heart cardiovascular system anatomy physiology davis icc
Chapter 15 Cardiovascular System ICC:Davis
Serous membrane, double-layered sac that covers the heart and proximal ends of its large blood vessels.
The inner layer of the sac that covers the heart.
The outer layer of the sac that covers the heart.
The space between the visceral and parietal layers, filled with serous fluid to reduce friction.
Hollow, cone-shaped muscular pump.
Where is the heart located?
within the mediastinum of throacic cavity
Distributes oxygen and nutrients to cells, carries carbon dioxide and wastes from cells, maintains acid-base balance of blood, protects against disease, prevents hemorrhage by forming blood clots, and helps regulate body temperature.
____of the heart is the top and ____ is the bottom.
Same as the visceral pericardium, protective outermost layer, connective tissue covered by epithelium, includes blood and lymph capillaries, fat, and nerve fibers.
Middle layer of the heart wall, consists mainly of cardiac muscle that pumps blood out of chambers, has blood and lymph capillaries and nerve fibers.
Inner lining of the chambers and valves of the heart.
SPecialized cardiac muscle fibers made of epithelium and connective tissue with many collagenous and elastic fibers and blood vessels.
Where are purkinje fibers found?
The upper chambers of the heart which receive blood returning to the heart.
Earlike projections found outside of each atrium.
Lower chambers of the heart, which force blood out.
Seperates the left and right sides of the heart.
What seperates the left and right atria?
What seperates the right and left ventricles?
Opening between atrium and ventricle on each side, guarded by an AV valve.
Bring deoxygenated blood back to the heart.
What are the three veins which return blood to the right atrium?
superior vena cava
inferior vena cava
Returns blood from above the heart to the right atrium.
superior vena cava
Returns blood from below the heart to the right atrium.
inferior vena cava
Returns blood from the myocardium of the heart to the right atrium.
What are the four veins which return blood to the left atrium?
Return blood from the lungs. The only red veins.
The artery which carries blood away from the right ventricle.
Branches into the right and left pulmonary arteries that carry blood to each lung.
The artery which carries blood away from the left ventricle.
Distributes blood to all parts of the body other than the lungs.
Located in the atrioventricular orifice between the atrium and ventricle.
The valve betweeen the right atrium and right ventricle.
The valve between the left atrium and left ventricle.
bicuspid (mitral) valve
Valve between the right ventricle and its artery and between the left ventricle and its artery.
Valve between the right ventricle and the pulmonary trunk.
pulmonary (semilunar) valve
Between the left ventricle and the aorta.
aortic (semilunar) valve
Found in ventricles and contract when ventricles contract, helping to close the tricuspid and bicuspid valves.
Fibrous strings that attach muscles and valves.
Papillary muscles and chordae tendineae are not found here.
What is the path of blood through the heart?
superior vena cava
inferior vena cava
right/left pulmonary arteries
lungs (for oxygen)
right/left pulmonary veins
aortic semilunar valve
all parts of the body
Consists of blood vessels that carry blood from the heart to the lungs and back to the heart.
Consists of blood vessels that carry blood from the heart to all parts of the body, except the lungs, and back again.
Explain coronary circulation.
The first 2 branches of the aorta are the right and left coronary arteries which supply the heart tissues. Blood leaving heart tissue drains into cardiac veins that join the coronary sinus which empties into the right atrium.
Hooks together the arteries which lead to the digestive organs and hepatic vein.
hepatic portal system
Provides oxygen to the stomach, liver, duodenum, pancreas, and spleen
Provides oxygen to the pancreas, small intestine, and large intestine.
superior mesentric artery
Where does the hepatic portal system begin and end?
How is blood drained from the abdominal viscera?
by way of the hepatic portal system
Capillaries from the stomach, intestines, pancreas, and spleen carry blood to the hepatic portal vein leading where?
Hepatic portal blood is low in oxygen but rich in what?
digestive substances or nutrients
Stores nutrients such as glucose, regulates/monitors the level of glucose, and detoxifies poisons and destroys bacteria.
Carries digestive substances into the liver where it breaks up into a network of capillaries or sinuses.
hepatic portal vein
When blood leaves the liver through a series of hepatic veins, where does it go?
inferior vena cava
A series of contractions that constitutes a complete heart beat.
Blood moves through the heart due to contractions and the natural flow from ___ pressure areas to ____ pressure areas.
When the ventricles contract.
When the ventricles relax.
During ventricular contraction when A-V valves are closing, what sound do you hear?
During ventricular relaxation when the pulmonary and aortic valves are closing, what sound do you hear?
What sound does the heartbeat make?
An abnormal sound caused by a valve not closing properly and blood leaks by through the valve.
A mass of merging muscle fibers that act as a unit.
What are atrial cyncytium and ventrical cyncytium connected by?
fibers of the cardiac conduction system
Specialized muscle tissue that initiates and conducts impulses causing cardiac muscle to contract.
cardiac conduction system
A-V bundle/bundle of His
What are the components of the cardiac conduction system?
S-A node, A-V node, A-V bundle, purkinje fibers
Found in the posterior wall of the right atrium, this sets the basic pace for the heart rate and initiates each cardiac cycle.
Located in the floor of the right atrium near the interatrial septum, impulses travel from here to the A-V bundle.
Branches that lead to purkinje fibers.
Located in the endocardium of the ventricles, impulse travels along these to cardiac muscle causing ventricles to contract.
A recording of waves that reflect the electrical changes in the myocardium during a cardiac cycle.
Small upward waves on an ECG.
Leads to the contraction of the atria, the spread of an impulse from the S-A node through the two atria.
Small downward, then large upright wave on an ECG which ends as a downward wave.
Leads to the contraction of the ventricles, the spread of the impulse through the ventricles.
Upward wave on an ECG
On an ECG, what is happening during a T-wave?
Skeletal muscles require more blood so the heart rate increases in response.
Cause heart action to decrease, arising from the medulla oblongata and are part of the vagus nerve.
Cause heart action to increase, arising from the spinal cord and are part of the accelerator nerves.
What does increased temp do to your heart rate?
increases heart rate
What does decreased temp do to your heart rate?
decreases heart rate
What does excess K+ do to heart rate?
decrease rate and force of contractions
What does excess Ca2+ do to heart rate?
increase heart action
Fast heartbeat (over 100/min), causes: increase in body temp, stimulation by sympathetic fibers, drugs and hormones, heart disease, excitement, exercise
Slow heart rate (less 60/min) Causes: decreased body temp, stimulation from parasympathetic fibers, drugs, sleeps, athletes.
(Premature) impulse originates from site other than the S-A node.
Heart contracts regularly but very rapidly (250-350/min)
Uncoordinated contractions, atrial not life threating but ventricular may be fatal.
General pathway of blood vessels.
Arterial wall made of endothelium of squamous epithelium for a smooth interior surface, connective tissue with elastic and collagenous fibers.
Arterial wall made of smooth muscle and elastic connective tissue.
Arterial wall made of a thin layer of connective tissue that attaches to surrounding tissue.
Branches in arterioles that join capillaries.
Bypass capillaries and lead to venules.
Connect arterioles and venules.
Flow in capillaries is regulated by ____, open when cells are low in O2 and nutrients.
Permits transfer of substances between tissues and blood.
capillary exchange (microcirculation)
Bidirectional governed by concentration gradients. Most important means of transport.
Caused by blood pressure and osmotic pressure do to the effect of plasma proteins.
Another name for blood pressure
At the arteriolar end of the capillaries, bp is higher than osmotic pressure, so ____ predominates.
At the venular end, the osmotic pressure stays the same, but the bp decreases, so ____ predominates.
Filtration ____ along the capillary
Normally, more fluid leaves the capillaries than returns. Excess fluid is collected by ____ and returned through the ____.
Fluid in the blood minus the plasma proteins.
Connect capillaries to veins with walls that are similar to arteriole walls but thinner and less muscle/elastic tissue is present.
Return blood to the heart, similar walls to arteries but thinner with less muscle and elastic tissue, and can contain valves.
70% of blood is found here and is referred to as what?
Due to decreased filtration at the venules and the inability of the right ventricle of the heart to pump blood out as rapidly as it enters, ____ may occur.
Functions as blood reservoirs so that bp will be maintained in times of blood loss.
How much blood volume can be lost and still maintain normal blood flow?
An accumulation of fatty material (plaque) inside an artery
The state of atherosclerosis in which the arteries harden.
An artery dilates and forms and pulsating sac.
An inflammation of a vein.
The presence of abnormal dilations in superficial veins.
What are the risk factors of varicose veins?
heredity (more common in women)
prolonged periods of standing
The force exerted by the blood against the inner walls of blood vessels.
Where is blood pressure normally taken?
Normal systolic pressure/diastolic pressure.
Blood pressure ____ as it moves through the arterial system.