Circulatory System Review

A set of flashcards covering key vocabulary and concepts related to the circulatory system, including types of circulation, heart structure, blood composition, and cardiovascular health.

Circulatory System

Transports nutrients, gases, hormones, and waste products.

Gastrovascular cavity

Internal cavity responsible for both digestion and circulation of nutrients, found in cnidarians and flatworms.

Circulatory system

An internal transport system composed of a circulatory fluid, a series of tubes, and a muscular pump.

Open circulatory systems

Circulatory fluid is pumped into a series of open-ended vessels, flowing among organs and tissues; fluids called hemolymph.

Hemolymph

Circulatory fluid in open systems that does not differ in composition from interstitial fluid.

Closed circulatory systems

Fluid is always contained in vessels; the circulatory fluid is blood.

Annelids

Type of organism that has a closed circulatory system.

Nematodes

Type of organism that has a closed circulatory system.

Chordates

Type of organism that has a closed circulatory system.

Single circulation

Type of circulation with one path through the heart, common in fish.

Double circulation

Blood makes two circuits through the heart; includes pulmonary and systemic circuits.

Pulmonary circuit

Carries deoxygenated blood from the heart to lungs and oxygenated blood back to heart.

Systemic circuit

Carries oxygenated blood from the heart to the tissues and deoxygenated blood from the tissues back to the heart.

Three-chambered heart

Heart structure where deoxygenated blood enters on the right side and oxygenated on the left; found in amphibians and some reptiles.

Four-chambered heart

Heart structure with complete separation of oxygenated and deoxygenated blood; found in crocodilians, birds, and mammals.

Erythrocytes

Red blood cells that transport oxygen and lack a nucleus.

Leucocytes

White blood cells involved in the immune response.

Platelets

Cell fragments that play a crucial role in blood clotting.

Plasma

Watery matrix of blood containing water, ions, proteins, and transported substances.

Fibrinogen

A plasma protein converted to fibrin during blood clotting.

Clotting factors

Proteins in blood plasma that amplify the clotting process during blood vessel injury.

Atherosclerosis

Accumulation of plaque in the inner lining of arteries.

Angina pectoris

Chest pain due to partial blockage of a coronary artery.

Myocardial infarction

Heart attack due to complete blockage of a coronary artery.

Cardiac cycle

The complete cycle of filling and pumping of blood in the heart.

Diastole

Relaxation phase of the cardiac cycle when chambers fill with blood.

Systole

Contraction phase of the cardiac cycle when blood is pumped out of the heart.

Sinoatrial node (SA node)

Pacemaker of the heart that generates electrical signals.

Atrioventricular node (AV node)

Receives signals from the atria and delays them slightly for coordinated contraction.

Blood pressure

The force exerted by circulating blood on the walls of blood vessels.

Systolic pressure

Pressure in arteries during ventricular contraction.

Diastolic pressure

Pressure in arteries during ventricular diastole.

Cardiovascular disease

A group of disorders that affect the heart and blood vessels.

Hypertension

High blood pressure caused by reduced flexibility or partial blockage of an artery.

Stroke

Occurs when a cranial arteriole bursts or is blocked, causing lack of oxygen to part of the brain.

Congestive heart failure

Condition where the heart does not pump enough blood, leading to fluid build-up.

Factors affecting cardiovascular health

Includes smoking, drug abuse, alcohol consumption, weight gain, diet, and exercise.

Precapillary sphincters

Muscles that regulate blood flow through capillary beds.

Capillaries

Thin blood vessels that allow exchange between blood and interstitial fluid.

Arteries

Blood vessels that carry blood away from the heart.

Veins

Blood vessels that carry blood toward the heart.

Aorta

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

Superior vena cava

Vein that carries deoxygenated blood from the upper body to the heart.

Inferior vena cava

Vein that carries deoxygenated blood from the lower body to the heart.

Pulmonary arteries

Carry deoxygenated blood from the heart to the lungs.

Pulmonary veins

Carry oxygenated blood from the lungs to the heart.

Heart valves

Structures that prevent the backflow of blood in the heart.

Septum

Muscular wall separating right and left sides of the heart.

Electrocardiogram (ECG)

A recording of electrical signals in the heart.

Defibrillation

Application of an electrical current to the heart to restore normal rhythm.

Lymphatic vessels

Return excess fluids lost from capillaries back to the circulatory system.

Atrial fibrillation (A-fib)

Irregular or rapid contractions of the atria which can lead to clots.