Muscular System
The plasma membrane of a muscle fiber.
What is the sarcolemma?
This childhood disorder causes soft, weak bones due to a deficiency of vitamin D, calcium, or phosphate.
What is rickets?
The chamber of the heart that pumps oxygenated blood to the body.
What is the left ventricle?
This equation describes cardiac output.
What is CO = HR × SV?
An irregular heartbeat caused by abnormal electrical activity in the heart.
What is an arrhythmia?
The smallest functional contractile unit of muscle containing actin and myosin filaments.
What is a sarcomere?
This type of contraction produces tension but does not shorten the muscle.
What is an isometric contraction?
The valve located between the left atrium and left ventricle.
What is the mitral (bicuspid) valve?
The volume of blood ejected by the ventricle during one heartbeat.
What is stroke volume?
A condition in which the heart cannot pump enough blood to meet the body’s needs.
What is congestive heart failure?
The three functional characteristics of muscle tissue include excitability, contractility, and this ability to return to original shape after stretching.
What is elasticity?
This autoimmune disorder causes chronic inflammation of the joints and can lead to joint deformity.
What is rheumatoid arthritis?
The electrical impulse of the heart normally begins in this structure.
What is the sinoatrial (SA) node?
The amount of blood in the ventricle after it fills during diastole.
What is end-diastolic volume (EDV)?
This disorder occurs when fatty plaques build up in arterial walls.
What is atherosclerosis?
This theory explains muscle contraction as actin filaments sliding past myosin filaments without changing length.
What is the sliding filament theory?
This blood test is commonly elevated in patients with rheumatoid arthritis and is an antibody against IgG.
What is rheumatoid factor (RF)?
The phase of the cardiac cycle when the ventricles contract and eject blood.
What is systole?
This law states that increased ventricular filling stretches the myocardium and increases contraction strength.
What is the Frank-Starling law?
A life-threatening rhythm where the ventricles quiver instead of pumping blood.
What is ventricular fibrillation?
This structure stores calcium ions that are released to trigger muscle contraction.
What is the sarcoplasmic reticulum?
This condition describes a reversible decrease in the muscle’s ability to generate force due to ATP depletion and ionic imbalance.
What is muscle fatigue?
This structure carries oxygenated blood from the lungs to the left atrium.
What are the pulmonary veins?
This term describes the pressure the ventricle must overcome to eject blood.
What is afterload?
This condition involves severe hypotension that reduces blood flow to vital organs.
What is shock?