BIOL 1692 Terms (Units 5-8)

Angina (pectoris)

Chest pain caused by reduced blood flow to the heart muscle, often due to atherosclerosis.

Artery

A blood vessel that carries oxygenated blood away from the heart to the body.

Atherosclerosis

A condition in which fatty deposits (plaques) build up inside arteries, narrowing them and restricting blood flow.

Atrioventricular (AV) valves

The valves between the atria and ventricles that prevent backflow of blood.

Atrium

One of the two upper chambers of the heart that receive blood from the veins.

AV node (Atrioventricular node)

A part of the heart’s electrical system that delays impulses before they pass to the ventricles.

Bradycardia

A slower-than-normal heart rate, typically below 60 beats per minute.

Capillary

The smallest blood vessels where gas, nutrient, and waste exchange occur between blood and tissues.

Cardiac arrest

A sudden loss of heart function, often due to electrical disturbances.

Cardiac output

The amount of blood the heart pumps per minute, calculated as stroke volume × heart rate.

Chordae tendineae

Tendinous cords that anchor the AV valves to the heart’s ventricles.

Coronary arteries

Blood vessels that supply oxygen-rich blood to the heart muscle.

Coronary veins

Blood vessels that drain deoxygenated blood from the heart muscle and return it to the right atrium.

Diastole

The phase of the cardiac cycle when the heart relaxes and fills with blood.

Ectopic

Refers to an abnormal location or abnormal heartbeat originating outside the SA node.

Electrocardiogram (ECG/EKG)

A test that records the electrical activity of the heart.

Endocardium

The inner lining of the heart chambers and valves.

Epicardium

The outermost layer of the heart, part of the pericardium.

Fibrillation

Rapid, irregular heartbeats; atrial fibrillation affects the atria.

Heart rate

The number of heartbeats per minute.

Medulla (oblongata)

The part of the brainstem that regulates vital functions, including heart rate.

Myocardial infarction

Death of heart muscle tissue due to a blocked coronary artery.

Myocardium

The thick, muscular layer of the heart responsible for contractions.

Myocyte

A muscle cell, specifically referring to cardiac muscle cells.

P wave

The part of an ECG representing atrial depolarization.

Pacemaker

A device or natural structure that regulates the heart’s rhythm.

Parasympathetic

Part of the autonomic nervous system that slows heart rate.

Pericardium

A protective sac surrounding the heart.

Pulmonary

Referring to the lungs; the pulmonary circulation carries blood between the heart and lungs.

QRS complex

The part of an ECG that represents ventricular depolarization.

SA node (Sinoatrial node)

The heart’s natural pacemaker.

Semilunar valves

The aortic and pulmonary valves that prevent blood from flowing back into the ventricles.

Stroke volume

The amount of blood ejected from the ventricle per heartbeat.

Sympathetic

Part of the autonomic nervous system that increases heart rate.

Systemic

Refers to the circulation that delivers oxygenated blood to the body.

Systole

The phase of the cardiac cycle when the heart contracts.

T wave

The part of an ECG representing ventricular repolarization.

Tachycardia

A fast heart rate, typically over 100 beats per minute.

Thrombus

A blood clot that can block blood flow.

Vein

A blood vessel that carries deoxygenated blood back to the heart.

Ventricle

One of the two lower chambers of the heart that pump blood.

Anastomoses

Connections between blood vessels that allow for alternate routes of blood flow.

Aneurysm

A weakened, bulging section of an artery.

Angiotensin II

A hormone that constricts blood vessels and increases blood pressure.

Aorta

The largest artery in the body, carrying oxygenated blood from the heart.

Arteriole

A small artery that leads into capillaries.

Baroreceptor

A pressure-sensitive sensory receptor in blood vessels.

Blood colloid osmotic pressure

The pressure exerted by plasma proteins that pulls water into capillaries.

Brachiocephalic trunk

A major artery that branches from the aortic arch.

Carotid artery

A major artery in the neck that supplies blood to the brain.

Chemoreceptor

A sensory receptor that detects chemical changes.

Diffusion

The passive movement of molecules from higher concentration to lower concentration.

Edema

Swelling caused by excess fluid accumulation in tissues.

Fenestrated

Refers to capillaries with small pores for the exchange of larger molecules.

Filtration

The movement of fluid and solutes out of capillaries.

Hemorrhoid

Swollen veins in the rectum or anus.

Hypertension

High blood pressure, a chronic condition.

Hypotension

Low blood pressure, causing dizziness and fainting.

Jugular vein

A major vein in the neck that returns deoxygenated blood.

Mean arterial pressure (MAP)

The average blood pressure in arteries during a single cardiac cycle.

Natriuretic peptides

Hormones that promote sodium and water excretion.

Pulmonary trunk

The large artery that carries deoxygenated blood from the right ventricle.

Pulmonary veins

Veins that carry oxygenated blood from the lungs.

Pulse pressure

The difference between systolic and diastolic blood pressure.

Reabsorption

The process of taking back water and solutes from filtrate.

Sinusoid

A type of capillary with large openings for extensive exchange.

Stroke

A medical condition caused by lack of blood flow to the brain.

Subclavian artery

A major artery supplying blood to the arms.

Total peripheral resistance (TPR)

The resistance of blood flow in the circulatory system.

Tunica externa

The outermost layer of a blood vessel.

Tunica intima

The innermost layer of a blood vessel.

Tunica media

The middle layer of a blood vessel.

Varicose

Refers to enlarged, twisted veins.

Vena cavae

The two largest veins returning blood to the heart.

Venule

A small vein that collects blood from capillaries.

Albumin

A protein in blood plasma that helps maintain osmotic pressure.

Anemia

A condition with a deficiency of red blood cells.

Antibody

A protein produced by the immune system that binds to specific antigens.

Antigen

A substance that triggers an immune response.

Basophil

A type of white blood cell involved in inflammatory responses.

Eosinophil

A white blood cell involved in allergic reactions and fighting infections.

Erythrocyte

A red blood cell responsible for oxygen transport.

Erythropoiesis

The process of red blood cell production.

Erythropoietin (EPO)

A hormone produced by the kidneys stimulating red blood cell production.

Fibrinogen

A plasma protein converted into fibrin during blood clotting.

Globulin

A group of proteins in the blood that assist with immune function.

Hematocrit

The percentage of blood volume occupied by red blood cells.

Hemoglobin

A protein in red blood cells that binds oxygen.

Hemopoiesis

The process of blood cell formation.

Hemostasis

The process that stops bleeding.

Jaundice

A condition characterized by yellowing of the skin due to excess bilirubin.

Leukocyte

A white blood cell that is part of the immune system.

Leukopoiesis

The process of white blood cell formation.

Lymphocyte

A type of white blood cell involved in adaptive immunity.

Lymphoid

Refers to tissues and organs involved in immune responses.

Macrophage

A large immune cell that engulfs pathogens and debris.

Monocyte

A type of white blood cell that differentiates into macrophages.

Myeloid

Refers to blood cells derived from bone marrow.

Neutrophil

A white blood cell that is the first responder to infections.

Phagocytosis

The process of engulfing pathogens and debris.