Heart Physiology definitions Flashcards

A muscular organ that pumps blood through the circulatory system by rhythmic contraction and relaxation, divided into atria and ventricles, and regulated by electrical signals.

A vital fluid circulating through the heart, arteries, veins, and capillaries, delivering oxygen and nutrients to cells and removing waste products, while also playing a role in immune defense and temperature regulation.

Blood vessels that carry oxygen-rich blood away from the heart to the body's tissues, characterized by thick, muscular walls to withstand high pressure from heart contractions.

Thinner, less muscular heart chambers that receive blood from veins and transfer it to the ventricles for pumping into the arteries.

Muscular heart chambers that pump blood into arteries, playing a crucial role in the cardiac cycle by contracting during systole and relaxing during diastole to maintain blood circulation.

The contraction phase of the cardiac cycle where the heart muscles contract, pumping blood from the ventricles into the arteries.

The heart's relaxation phase, allowing chambers to fill with blood, crucial for maintaining efficient blood circulation.

The largest veins in the body, responsible for returning deoxygenated blood from the body to the right atrium of the heart.

Valves between the atria and ventricles that prevent backflow of blood during ventricular contraction, ensuring unidirectional flow from atria to ventricles.

Valves in the heart that prevent backflow of blood from the arteries into the ventricles during ventricular diastole, ensuring unidirectional blood flow.

Electrical signals generated by ion movement across cell membranes, crucial for initiating and propagating heart contractions, moving between heart cells via gap junctions.

A group of specialized cells in the right atrium that initiates and regulates the heart's rhythmic contractions by generating electrical impulses, often referred to as the heart's natural pacemaker.

A cluster of cells in the heart that delays electrical impulses, allowing the atria to fully contract and empty blood into the ventricles before they contract.

Specialized fibers in the heart's ventricles that rapidly conduct electrical impulses, ensuring coordinated contraction from the apex upwards, optimizing blood ejection into the arteries.

The volume of blood pumped by the ventricles per minute, calculated by multiplying heart rate (beats per minute) by stroke volume (blood per beat).