Circulatory System - Video Lecture Flashcards

Flashcards reviewing key concepts from the circulatory system lecture, including blood components, heart anatomy, vessels, and circulation.

What are red blood cells (RBCs) and what is their primary job?

Red blood cells, or erythrocytes, are the most abundant blood cells that carry oxygen from the lungs to the rest of the body and transport carbon dioxide back to the lungs.

What gives RBCs their red color?

Hemoglobin, an iron-containing protein that binds oxygen.

How big is the human heart and where is it located?

About the size of your fist; located beneath the sternum near the center of the chest.

What surrounds the heart?

A double-walled sac called the pericardium.

How many chambers does the heart have, and what separates the two sides?

Four chambers; the left and right sides are separated by the interventricular septum.

Name the three main components of the circulatory system mentioned in the notes.

The heart, the blood, and the blood vessels (arteries, veins, and capillaries).

What is the general function of arteries?

Arteries carry blood away from the heart; most arteries carry oxygen-rich blood, with the pulmonary artery carrying deoxygenated blood to the lungs.

What is the largest artery in the body and what is its function?

The aorta; it carries blood from the heart to the systemic circulation.

Which vessel carries blood from the heart to the lungs for oxygenation?

The pulmonary artery.

What are capillaries and why are they important?

Capillaries are delicate vessels with thin walls that deliver nutrients and oxygen to cells, remove carbon dioxide and waste, and connect arteries to veins to enable exchange.

What are veins and what is special about pulmonary veins?

Veins carry deoxygenated blood back to the heart; pulmonary veins carry oxygenated blood from the lungs to the left atrium.

What are heart valves and what do they do?

Heart valves control the direction of blood flow by opening and closing, ensuring blood moves in the correct direction.

Name the four heart valves.

Pulmonary valve, Aortic valve, Tricuspid valve, and Mitral valve.

What is the interventricular septum?

The wall that separates the left and right ventricles, preventing mixing of oxygenated and deoxygenated blood.

What are the right and left atria, and what do they do?

The right atrium receives deoxygenated blood from the body and pumps it to the right ventricle; the left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle.

How many chambers are in the heart and what are they called?

Four chambers: two atria (right and left) and two ventricles (right and left).

What are white blood cells and platelets?

White blood cells are part of the immune system and fight infection; platelets are cell fragments that help in blood clotting.

What percentage of blood is plasma, and what is plasma made of?

55% of blood is plasma; plasma is about 90% water and 10% dissolved minerals, proteins, and other substances.

What is the buffy coat?

The layer containing white blood cells and platelets that sits above red blood cells in centrifuged blood.

What is the function of plasma and what does it carry?

Plasma carries blood cells, nutrients, waste, antibodies, clotting proteins, and other substances; it is the liquid component of blood.

What is the function of the vena cava and what are its two parts?

Vena cava returns blood to the heart; the superior vena cava drains blood from the head, neck, arms, and chest, while the inferior vena cava drains the lower body back to the heart.

What is the aortic root and what is its function?

The root portion of the aorta where blood first exits the heart; it acts as the main conduit to the body's circulatory system.

What is pulmonary circulation?

The part of the circulatory system that moves blood between the heart and the lungs; pulmonary arteries carry deoxygenated blood to the lungs and pulmonary veins carry oxygenated blood to the heart.

Trace the flow of blood through the heart starting at the right atrium.

Right atrium → Right ventricle → Pulmonary artery → Lungs → Pulmonary veins → Left atrium → Left ventricle → Aorta.