chap 7

Vocabulary flashcards covering key terms and concepts from Chapter 7 of the cardiovascular system and its control.

Cardiovascular System

A system responsible for the circulation of blood and lymph through the heart and blood vessels.

Major Functions

Key roles of the cardiovascular system including delivering oxygen and nutrients, removing waste, transporting hormones, and regulating body temperature.

Myocardium

The heart muscle responsible for pumping blood; it has a highly oxidative capability and is similar to type I muscle fibers.

Heart Chambers

Four chambers of the heart: right atrium, left atrium, right ventricle, left ventricle.

Diastole

The relaxation phase of the cardiac cycle in which the heart chambers fill with blood.

Systole

The contraction phase of the cardiac cycle where the heart pumps blood out.

Stroke Volume (SV)

The volume of blood pumped from each ventricle during each heartbeat.

Ejection Fraction (EF)

The percentage of end-diastolic volume (EDV) that is pumped out of the heart with each heartbeat.

Cardiac Output (Q)

The total volume of blood the heart pumps per minute.

Cardiac Conduction System

A collection of heart cells that generate and spread electrical signals to coordinate heartbeats.

SA Node

The sinoatrial node, known as the heart's natural pacemaker.

AV Node

The atrioventricular node that relays electrical signals from the atria to the ventricles.

Intrinsic Heart Rate

The heart rate defined by the SA node independently of neural innervation, approximately 100 beats/min.

Parasympathetic Nervous System

A part of the autonomic nervous system that slows heart rate and reduces force of contraction.

Sympathetic Nervous System

Part of the autonomic nervous system that increases heart rate and force of contraction.

Vasoconstriction

The narrowing of blood vessels to reduce blood flow.

Vasodilation

The widening of blood vessels to increase blood flow.

Atherosclerosis

A disease in which plaque builds up inside arteries, leading to coronary artery disease.

ECG (Electrocardiogram)

A recording of the heart's electrical activity, used as a diagnostic tool.

Bradycardia

An abnormally slow heart rate, typically below 60 beats per minute.

Tachycardia

An abnormally high heart rate, typically above 100 beats per minute.

Blood Pressure

The pressure exerted by circulating blood against the walls of blood vessels.

Systolic Pressure (SBP)

The highest pressure in the arteries during the contraction of the heart.

Diastolic Pressure (DBP)

The lowest pressure in the arteries during relaxation of the heart.

Mean Arterial Pressure (MAP)

The average pressure in a patient's arteries during one cardiac cycle.

Metabolic Mechanisms

Regulation of blood flow based on local metabolic by-products.

Intrinsic Control of Blood Flow

The ability of local tissues to regulate their own blood supply by altering vessel diameter.

Functional Syncytium

The coordinated contraction of cardiac muscle fibers acting as a single functional unit.

Cardiac Cycle

All mechanical and electrical events occurring during one heartbeat.

Coronary Arteries

The arteries that supply blood to the heart muscle.

Chambers of the Heart

Includes the two atria and two ventricles responsible for receiving and pumping blood.

Blood Vessels

Includes arteries, veins, and capillaries that carry blood throughout the body.

Norepinephrine

A neurotransmitter that increases heart rate and force of contraction upon sympathetic stimulation.

Acetylcholine

A neurotransmitter released by the parasympathetic nervous system that decreases heart rate.

Arterioles

Small blood vessels that control blood flow and feed capillaries.

Capillary Exchange

The process through which nutrients and waste are exchanged between blood and tissues.

Ventricular Hypertrophy

An increase in the thickness of the heart's ventricular walls due to increased workload.

Intracellular Calcium Release

The process in which calcium is released within heart cells to initiate contraction.

Blood Viscosity

The thickness of blood; influenced by the number of red blood cells.

Hematocrit

The percentage of blood volume occupied by red blood cells.

Red Blood Cells (Erythrocytes)

Cells that transport oxygen and carbon dioxide in the bloodstream.

White Blood Cells (Leukocytes)

Cells involved in the immune response and protection against infection.

Platelets

Cell fragments that play a critical role in blood clotting.

Plasma

The liquid component of blood, making up about 55% of its volume.

Functional Sympatholysis

Inhibition of sympathetic vasoconstriction to allow increased blood flow to muscles during exercise.

Atrial Contraction

The phase when the atria contract to push blood into the ventricles.

Ventricular Repolarization

The process where the ventricles recover their resting state after contraction.

Baroreceptors

Receptors that sense changes in blood pressure.

Venous Return

The flow of blood back to the heart through the veins.

Respiratory Pump

Mechanism that aids in venous return during breathing.