3: Cardiovascular II: Conduction and Development

The sound of the heart valves closing during the cardiac cycle.

The first heart sound, 'Lub', is created by the closing of the atrioventricular (AV) valves at the beginning of systole (heart contraction).

The second heart sound, 'Dub', is created by the closing of the semilunar valves at the beginning of diastole (heart relaxation).

The process of listening to sounds within the body, specifically focusing on the heart, using a stethoscope.

Visceral sensory information related to blood pressure and blood composition is carried by chemoreceptors and baroreceptors to the CNS.

Specialized cardiac muscle cells that coordinate contraction of atria and ventricles, ensuring efficient and unidirectional excitation and contraction.

Located at the crista terminalis near the superior vena cava (SVC) and right atrium, this node is the primary pacemaker of the heart, initiating each heartbeat.

Situated at the opening of the coronary sinus, it relays electrical impulses from the atria to the ventricles.

A specialized bundle of conductive fibers extending from the AV node, dividing into left and right bundle branches, which distribute impulses to the ventricular walls.

Subdivisions of the atrioventricular bundle, these branches further divide into Purkinje fibers, allowing for synchronized contraction of the ventricular myocardium.

The autonomic nervous system controls heart rate and force of contraction.

Sympathetic nerves increase heart rate and force of contraction.

Parasympathetic nerves decrease heart rate and force of contraction.

Cardiac plexus is formed by parasympathetic (Vagus nerve) and sympathetic fibers.

Referred pain is when pain from internal organs is felt in another area of the body.

Somatic and visceral sensory neurons share pathways in the spinal cord leading to confusion in the sensory cortex.

Cardiac muscle is striated, branching, has large round nuclei, and has intercalated discs.

Intercalated discs are specialized junctions between cardiac muscle cells, allowing for efficient communication and synchronized contractions.

The functional unit of a muscle cell, containing the proteins responsible for contraction.

The outer layer of the heart, composed of connective tissue, fat, nerves, and blood vessels.

The middle layer of the heart, composed primarily of cardiac muscle tissue, responsible for the heart's pumping action.

The inner layer of the heart, lining the chambers and composed of connective tissue and endothelium.

The nucleus of a cardiac muscle cell, located centrally within the cell.

Striated muscle tissue responsible for the rhythmic contractions of the heart.