Chapter 11 - The Cardiovascular System: Heart, Blood Vessels, and Circulation

What does each side of the heart do?

What does each side of the heart do?

Left Side - Collects oxygen-rich blood from the lungs and propels it through the rest of the body.

Right Side - Collects oxygen-poor blood from the body and pumps it to the lungs.

Where in the thoracic cavity does the heart lie?

In the mediastinum (region that extends from the sternum to vertebral column and between the lungs)

What is the pericardium?

A protective sac that surrounds the heart.

What is an atrium and how many does the heart have?

A chamber that Collects blood from the circulation (right atrium and left atrium)

What is a ventricle and how many does your heart have?

A pump that delivers blood to the circulation (right ventricle and left ventricle).

What is the purpose of valves in the heart?

It helps to keep the blood flowing in the proper direction.

What is the myocardium?

The middle layer of the heart wall, composed of cardiac muscle.

What is the endocardium?

A protective layer that lines the inner chambers of the heart.

What does the Superior vena cava do? What about the inferior?

Brings blood from the heart from the head, upper body, and arms.

Brings blood from the lower body

What do the left and right coronary arteries do?

Carry blood to the heart muscle itself.

What do pulmonary arteries do?

Carry blood from the heart to the lungs.

What does the aorta do?

The artery that carries blood away from the heart to the body.

What is the cardiac conduction system?

A network of specialized muscle cells is found in the heart's walls that control heart beats.

What is an EKG/ECG?

It records the electrical changes accompanying a heartbeat.

What is arrhythmia?

An irregular heart rhythm.

What are some casues of arrhythmia?

Diseases, stress, drugs/other chemicals.

What are some examples of arrhythmia?

Supraventricular tachycardia, atrial flutter.

What is a systole?

The contraction phase of the cardiac cycle in which blood moves out of the heart chamber.

What is a diastole?

The relaxation phase of the cardiac cycle in which the heart chamber is resting and filling with blood.

How long is each cardiac cycle?

0.8 seconds

What is stroke volume?

The amount of blood ejected during each beat.

How can cardiac output (the volume of blood ejected from the heart per minute) be affected?

Through the autonomic nervous system (stress), hormones, age, gender.

What are anastomoses?

When blood vessels branch so blood can reach specific cells.

What do anastomoses help to do?

Maintain sufficient blood supply to an organ when one of the branches is blocked.

What are the conditions called when blood flow in the coronary arteries gets partially and totally blocked?

myocardial ischemia and myocardial infarction

What are the three functions of blood vessels?

Carries blood away and to the heart, exchanges substances, obtains nutrients and transports oxygen.

What is the lumen?

A hollow area in arteries that blood flows.

What are the walls of arteries and arterioles called?

tunics

What is it called when the arterial walls contract and narrow the lumen?

vasoconstriction

What is it called when the arterial walls relax and expand the lumen?

vasodilation

What are the three walls called that surround the lumen in arteries and arterioles? (go from outer to inner)

Tunica externa, tunica media, tunica intima.

What is a capillary?

A thin-walled, microscopic vessel containing of only an endothelial layer and a basement membrane.

How are nutrient-rich fluids moved out of the capillar?

Through filtration

What is autoregulation?

The ability of tissues to adjust blood flow based on local conditions

What are valves?

Inward folds of the tunic intima (innermost layer of veins and venules) that prevent blood from flowing backwards.

What is the skeletal muscle pump?

A collection of skeletal muscles that aid the heart in the circulation of blood

How does the respiratory pump work?

When you breathe in, the diaphragm moves downward, which increases the pressure in the abdominal cavity, moving the blood into thoracic veins.

What happens in pulmonary circulation?

The pulmonary arteries carry deoxygenated blood while the veins carry oxygenated blood.

What happens in hepatic portal circulation?

THe liver receives venous blood through a portal vein (called the hepatic portal vein).

What is a portal vein?

A vein that carries blood from one capillary network to another.

What favors increase blood pressure?

Increased force of contraction, drugs, increased blood volume.

What are the two neutral mechanisms that regulate blood pressure?

The cardiac and vasomotor centers.

What do the cardiac anvasomotor centers do?

They regulate blood pressure by using baroreceptors (neurons capable of responding to changes in blood), proprioceptors (sense movements), chemoreceptors (sense pH).

What is the baroreceptor reflex?

It uses hormones and receptors to detect changes in blood pressure and controls the heart to get it back to normal.

What is hypertension?

Chronic high blood pressure.

What are some effects of hypertension?

Stroke, heart failure, kidney failure.

What hormones maintain blood pressure?

Angiotensin II (AII) (this increases it), Antidiuretic hormone (increases water absorption), and ANP (causes a reduction in blood volume AKA lowers blood pressure).