cardiovascular/circulatory system

cardiovascular system comprised of

heart, blood vessels, and blood

cardiovascular system functions

• Transportation of O2 and CO2, nutrients, and waste products

• Regulation of body temperature and internal organ function

• Protection via immune system fighting infection and limiting blood loss via clotting

lymphatic system comprised of

lymph nodes, lymph vessels, and lymph

lymphatic system functions

• Removes excess fluid from tissues, filters it, & returns it to the bloodstream

• Aids with fighting infection

base of heart location

behind sternum at height of 2nd intercostal space

apex of heart location

along left midclavicular line at height of 5th intercostal space

endocardium

inside tissue lining of heart

myocardium

muscular tissue layer

epicardium

outside tissue lining of heart

pericardium

fluid-filled sac that surrounds heart (epicardium)

chambers of heart

• Right atrium (RA)

• Right ventricle (RV)

• Left atrium (LA)

• Left ventricle (LV)

atrioventricular valves

• cause “lub” when they close

• tricuspid valve: between RA and RV

• mitral/bicuspid valve: between LA and LV

semilunar valves

• cause “dub” when they close

• pulmonic valve: between RV and pulmonary artery

• aortic valve: between LV and aorta

blood flow through the heart

1. Superior/Inferior vena cava

2. RA

3. tricuspid valve

4. RV

5. pulmonic valve

6. pulmonary arteries

7. lungs

8. pulmonary veins

9. LA

10. bicuspid valve

11. LV

12. aortic valve

13. aorta

14. body

conduction system of heart does not

rely on input from nervous system like skeletal muscle

SA node is the heart’s

“pacemaker”

transmission of heart conduction system

1. SA node

2. AV node

3. Bundle of His

4. Bundle branches

5. Purkinje fibers

heart rate (HR)

number of times heart beats per minute

stroke volume (SV)

volume of blood pumped with each heartbeat

cardiac output (CO)

volume of blood pumped per unit of time (CO = HR x SV)

influence from ANS: parasympathetic input

causes decreased HR

influence from ANS: sympathetic input

causes increased HR

electrocardiogram (ECG/EKG)

measures electrical activity of heart using surface electrodes

P wave

depolarization of atria

QRS complex

depolarization of ventricles

ST segment

delay before repolarization of ventricles

T wave

repolarization of ventricles