heart anatomy
What is the size of the average adult human heart?
about he size a fist
Which side of the heart is primarily responsible for pumping deoxygenated blood to the lungs?
the right side
What causes the "lub-dub" sound of the heartbeat?
The closing of the heart valves.
What does an EKG (or ECG) record?
The electrical activity of the heart.
About how many times does the human heart beat in a single day?
100,000
about the size of a plum
What is the primary function of heart valves?
To prevent the backflow of blood and ensure it flows in only one direction.
What is the medical term for the contraction phase of the heartbeat when blood is pumped out?
Systole.
What is the average resting heart rate for a healthy adult?
Between 60 and 100 beats per minute.
On average, how many gallons of blood does the heart pump each day?
2,000
Which major organ system relies on the heart to function
the cardiovascular system
Which blood vessels carry oxygen-rich blood away from the heart to the rest of the body?
arteries
What is the relaxation phase of the heart called, when the chambers fill with blood?
Diastole.
What happens to your heart rate when the sympathetic nervous system is activated (e.g., during exercise or stress)?
It increases.
Roughly how many miles of blood vessels are in the adult human body?
about 60,00 miles
how many chambers are in the heart
4 chambers
What is the name of the largest artery in the human body?
The aorta.
What are the specialized cells in the right atrium that act as the heart's natural pacemaker?
The sinoatrial (SA) node.
In an ECG wave, what does the P-wave represent?
The electrical depolarization of the atria right before they contract.
What medical device was historically wheeled around on carts before becoming portable?
The first artificial pacemakers.
What is the innermost, smooth layer of tissue that lines the heart's chambers and valves?
What is the exact sequence of the four heart valves that a red blood cell passes through starting from the right atrium?
Tricuspid valve --> Pulmonary valve -->rMitral (bicuspid) valve --> Aortic valve.
In the cardiac cycle, what is the isovolumetric contraction phase?
The brief period where the ventricles begin to contract while all four valves are closed, causing pressure to rise rapidly without a change in blood volume.
What is the Frank-Starling law of the heart?
The principle that the stroke volume of the heart increases in response to an increase in the volume of blood filling the heart (end-diastolic volume) before contraction.
Which condition is characterized by the medical event where all of the internal organs (including the apex of the heart) are mirrored on the opposite side of the body?
Situs inversus.