Cardiovascular and Nervous System

Tonometry is a diagnostic test that measures intraocular pressure (IOP) within the eye. It is primarily used to screen for and monitor glaucoma, a condition where increased eye pressure can damage the optic nerve and lead to vision loss.

The average human heart beats about 72 times per minute at rest. Over 24 hours, this equals approximately 72 × 60 × 24 = 1,03,680 beats. This matches option A (1,03,689), which accounts for normal variations in heart rate throughout the day due to activity, stress, and sleep cycles.

The typical cardiac output for a healthy adult at rest is 5-6 liters per minute. This represents the total volume of blood pumped by both ventricles combined. Values of 1-4 liters are too low for normal cardiac function. The heart pumps approximately 70-80 mL per beat, and at 70 beats per minute, this equals about 5 liters per minute.

The average healthy adult human has a resting pulse rate of approximately 72 beats per minute, with normal range typically 60-100 bpm. Options like 16 bpm are far too low (bradycardia), while 100 bpm is at the upper limit of normal. 65 bpm is within normal range but 72 is the standard average.

The pericardium is a protective, fluid-filled double-layered sac that encloses the heart and reduces friction during heartbeat. Myocardium is heart muscle tissue, ventricle is a chamber, and septum is the dividing wall between heart chambers.

The sinoatrial (SA) node initiates each heartbeat by generating electrical impulses that spread through the heart's conduction system, earning it the 'pacemaker' designation. The AV node delays impulses, Purkinje fibers conduct them to ventricles, and endocardium is the heart's inner lining.

Angina pectoris is chest pain or discomfort due to coronary heart disease. It manifests as pressure or squeezing (distractor 2) and can become unstable (distractor 3) when occurring at rest or with increased frequency.

Hypertension is the medical term for chronically elevated blood pressure. Hypotension refers to low blood pressure, which is the opposite condition. Malignant hypertension is a severe form of high blood pressure, but not the general term.

The heart sounds ('lub-dub') are created by the heart valves closing. The first sound (lub) comes from the mitral and tricuspid valves closing, and the second sound (dub) comes from the aortic and pulmonary valves closing. The correct answer is True.

Blood pressure readings consist of two numbers expressed as a fraction (e.g., 120/80 mmHg). The upper number represents systolic pressure, which is the pressure in arteries when the heart beats and pumps blood out. The lower number is diastolic pressure, which is the pressure when the heart rests between beats.

Women's hearts typically beat faster than men's - about 78-82 beats per minute for women versus 70-72 for men. This difference is due to women generally having smaller hearts that must work harder to pump blood.

Beta-blockers work primarily by blocking the effects of epinephrine (adrenaline) on beta receptors, which results in decreased heart rate and reduced blood pressure. They do not prevent clots (that's antiplatelets/anticoagulants), dilate veins (that's vasodilators), or increase heart rate (that would be counterproductive for their purpose).

ECG (electrocardiogram) records the heart electrical activity and is the primary diagnostic tool for cardiac arrhythmias, heart attacks, and other heart conditions. It does not diagnose brain, kidney, or lung conditions - those use EEG, renal function tests, and spirometry respectively.

A normal adult resting heart rate is approximately 60-100 beats per minute, with 72 bpm being a commonly cited average. Option B (70) falls within this normal range.