Circulatory System Review

What is the term used to describe general disorders with the arteries of the heart (that form over time)? What happens when you have it? Symptoms?

- Arteriosclerosis: walls of arteries thicken & lose elasticity. - chest pains, blood clots, shortness of breath, heart attack, or heart failure.

What are the AV Valves on the right side of the heart called? What about the left?

- Right side: AV (tricuspid) valves - Left side: AV (bicuspid) valves

What is stroke volume and why does it affect cardiac output?

- Stroke volume: amount of blood forced out of the heart with each heartbeat.

What are some treatment options for arteriosclerosis?

- clot-busting medicines - surgery: which force arteries open or create new pathways to bypass a blocked vessel.

What are the four chambers in the heart, and where are they?

- right atrium: top of the right side - right ventricle: bottom of the right side - left atrium: top of the left side - left ventricle: bottom of the left side

What are the 3 main types of blood vessels?

1. Arteries 2. Veins 3. Capillaries

What are the 3 pathways of the circulatory system, and what are they responsible for?

1. Pulmonary Pathway: carries O2 poor blood from heart to lungs, O2 rich blood from lungs to heart. 2. Systemic Pathway: carries O2 rich blood from heart to body tissues, O2 poor blood from tissues to heart. 3. Coronary Pathway: Provides blood to the heart itself.

What are the 3 major components of the circulatory system?

1. The Heart 2. The Blood Vessels 3. The Blood

List 2 indicators of good cardiovascular fitness.

1. low resting heart rate: stroke volume high, average cardiac output maintained w/ less work → efficient heart 2. Short heart rate recovery time after physical work.

What is the aorta?

A large artery which carries oxygenated blood to the body.

What is the septum (in the heart)?

A muscular wall that separates the two ventricles and atria.

What are capillaries?

A network of tiny blood vessels that join each artery and vein together.

Why does blood pressure increase when heart rate increases?

As heart rate increases, ventricles have to push more volume of blood per unit of time, therefore pressure increases.

What is blood pressure?

Pressure exerted against blood vessel walls as circulating blood passes through.

What does the left side of the heart do?

The left side receives oxygen-rich blood from the lungs and pumps it to the body.

What controls the rate and strength of a heartbeat?

The nervous system.

What does the right side of the heart do?

The right side receives oxygen poor blood coming from the body, and pumps it to the lungs.

What are the pulmonary veins?

They carry oxygen-rich blood from lungs to left side of heart.

When in the heartbeat make a lubb and dubb sound?

lubb sound: atria - systole, ventricle - diastole dubb sound: atria - diastole, ventricle - systole

What 2 factors affect cardiac output?

Stroke volume and heart rate.

What is the term used to describe heart disorders caused by genes? What are some common defects due to these defected genes?

- Congenital cardiovascular disorders - Common defects: heart murmur (misflow of blood in heart), valve defects (not opening/closing properly)

Why does heart rate affect cardiac output?

- Heart rate is the # of heartbeats/min THEREFORE... - related to volume of blood returning to heart.

List one characteristic of an artery and its importance.

- Highly elastic which allows them to expand and snap back as blood passes through. Helps to keep one-way blood flow.

What is the difference between arteries & veins in the systemic pathway, and arteries & veins in the pulmonary pathway?

- In the systemic pathway, arteries carry O2-rich blood & veins carry O2-poor blood. - In the pulmonary pathway, arteries carry O2-poor blood & veins carry 02-rich blood.

How is systolic and diastolic pressure used to express a blood pressure? What is another unit to express blood pressure?

- Systolic pressure presented over diastolic pressure in a fraction (ex. 120/80) - BP can also be shown in mm Hg (ex. below 120 mm Hg, above 80 mm Hg)

What is systolic and diastolic pressure?

- Systolic pressure: maximum pressure during a ventricular contraction. - Diastolic pressure: lowest pressure that occurs before ventricles contract again.

Since veins are not as elastic as arteries, how do they ensure one-way blood flow?

- The contraction of muscles around the veins ensure one way blood flow. - Veins also have valves that close after blood passes through so it can't go backwards.

Changes in blood pressure correspond to phases AND rate of the heart beat. Explain these changes.

- When ventricles contract (and force blood into pulmonary arteries & aorta) → pressure INCREASES. - When ventricles relax → pressure DECREASES. - When heart rate increases, pressure increases.

What are the vena cavae?

- both on right side - superior vena cava: receives oxygen-poor blood from head, chest, & arms - inferior vena cava: receives oxygen-poor blood from everywhere else

Trace the blood flow through the coronary pathway.

- capillaries receive blood from 2 coronary arteries that split off from the aorta. - each artery branches into smaller vessels and covers the entire heart - O2 moves through these vessels to capillary bed; gas exchange occurs. - O2 poor blood moves through vessels which get bigger and bigger → forms coronary veins - coronary veins go into right ventricle where it follows the pulmonary pathways.

What is systole and diastole?

- systole: phase of the heartbeat when the heart muscles contract and pumps the blood from the chambers to the arteries (systemic). - diastole: phase of the heartbeat when the heart muscles relax and allow the chambers to fill with blood.

How many valves does the heart have, what are they called, and why are they important?

- the heart has 4 valves - 2 of the valves are called: AV Valves - other 2 are called: semi-lunar valves - they ensure one way blood flow through the heart.

Trace the pulmonary and systemic pathway starting from oxygen-poor blood coming into the heart.

1. O2 poor blood enters the pulmonary pathway by flowing through the vena cave into the right atrium. 2. Atria contract, blood pumped into right ventricle. 3. Ventricle contract, pumps blood to pulmonary arteries. 4. Pulmonary arteries take O2 poor blood to lungs for gas exchange in the capillaries. 5. O2 rich blood transferred to the pulmonary veins. 6. Pulmonary veins lead to the left atrium. 7. Blood is now in the systemic pathway. 8. Atria contract again, blood pumped into left ventricle. 9. Ventricle contract, pumps blood to aorta where it goes to the body.

What are the 3 main functions of the circulatory system?

1. Transports gases (from respiratory system), nutrients (from digestive system), and wastes (from excretory system). 2. Regulates internal temperature & transports hormones. 3. Protects against blood loss from injury/disease.

Explain how capillaries help blood to exchange materials with body tissues (systemic pathway)?

Blood travels from an artery into the capillaries → in the capillaries, the gases & nutrients transferred into tissues cells → wastes move into blood → blood then moves out of the capillaries and into veins → blood goes back to heart.

What are the pulmonary arteries?

Both left and right pulmonary arteries take blood from the right side of the heart to the lungs.

Main function of the blood?

Carries nutrients, gases, and wastes through the body.

What are veins (in a systemic pathway)?

Carry oxygen-poor blood toward the heart (from body tissues).

What are arteries (in a systemic pathway)?

Carry oxygen-rich blood to the body. (i.e. see "aorta")

Main function of the heart?

Pushes blood through the body with its pumping action; generates blood flow.

How does regular cardiovascular exercise affect the heart?

Regular exercise increases resting stroke volume BECAUSE it increases stretchiness, strengthens the walls of, and enlarges the ventricular chambers. AS A RESULT, heart has more power to force out more blood.

Explain how the Sinoatrial (SA) and Atrioventrical (AV) nodes work to generate a heartbeat.

SA node (bundle of specialized muscle tissue in right atrium) generates electrical impulse → impulse causes atria to contract → when the atria contract, the electrical impulse from the SA node reaches the AV node → the AV node transmits the electrical impulse to the "bundle of His" (specialized fibre) → the bundle of His transmits this signal to the Purkinje Fibres → initiates contraction of ventricles → rhythmic heart beat as blood is pumped.

Main function of the blood vessels?

Serve as roadways for the blood to move through.

What is the circulatory system?

The system of vessels that transports blood - and the cells & substances within it - throughout the body.

What is cardiac output? What unit is is measured in? What does it indicate?

Amount of blood pumped by the heart. mL/min. Indicates level of O2 delivered to body, and amount of work that the body can perform.

What can you use to measure the electrical activity in the heart?

An electrocardiogram (ECG) machine.