Circulatory system Flashcards
(32 cards)
What are the four chambers of the heart?
2 atria and 2 ventricles
What major veins are associated with the heart?
Superior vena cava and pulmonary veins
What are the major arteries of the heart?
Aorta and pulmonary trunk
What is the pulmonary circuit?
The blood pathway between the right side of the heart, to the lungs, and back to the left side of the heart
What is the systemic circuit?
The pathway between the left and right sides of the heart
What are the functions of the heart?
- Generating blood pressure
- Routing blood
- Ensuring one-way blood flow
- Regulating blood supply
What is the role of the pericardium?
Covers and protects the heart
What are the three layers of the heart wall?
- Epicardium
- Myocardium
- Endocardium
What is the function of the sinoatrial (SA) node?
Times heart beats and causes atria to contract
What heart rate is considered tachycardia?
Heart rate in excess of 100 bpm
What heart rate is considered bradycardia?
Heart rate less than 60 bpm
What does the cardiac cycle consist of?
- Systole (contraction)
- Diastole (relaxation)
What type of circulatory system do humans have?
Closed circulatory system
What are the functions of the circulatory system?
- Transport nutrients, O2, CO2, hormones, blood cells, enzymes
- Nourishment
- Immunity / fighting diseases
- Thermoregulation
- Regulation of pH
- Homeostasis
What is systolic pressure?
Pressure when the heart contracts (120 Torr)
What is diastolic pressure?
Pressure between heart beats (80 Torr)
What causes the first heart sound or ‘lubb’?
Closure of atrioventricular valves and surrounding fluid vibrations at the beginning of ventricular systole
What causes the second heart sound or ‘dupp’?
Closure of aortic and pulmonary semilunar valves at the beginning of ventricular diastole
What is intrinsic regulation of the heart?
Results from normal functional characteristics, not on neural or hormonal regulation
What is Starling’s law of the heart?
The intrinsic regulation of heart function based on the heart’s filling
What is the role of parasympathetic stimulation in heart regulation?
Decreases heart rate, supplied by the vagus nerve
What is the role of sympathetic stimulation in heart regulation?
Increases heart rate and force of contraction, involves epinephrine and norepinephrine
What is hypertension?
High blood pressure that puts people at risk for heart disease
What is a heart murmur?
An abnormal heartbeat caused by valve problems
