Overview of the Circulatory System and Blood Functions

What is the primary function of the circulatory system?

To transport blood, oxygen, carbon dioxide, nutrients, and other molecules around the body.

What are the four main functions of blood?

1. Transport nutrients and molecules 2. Regulate body temperature 3. Protect against pathogens 4. Clotting to prevent blood loss.

Why is the left ventricle thicker than the right ventricle?

It has to pump blood a further distance at high pressure.

What are the three types of blood vessels?

1. Arteries - carry blood away from the heart 2. Veins - carry blood towards the heart 3. Capillaries - enable the exchange of materials at tissues.

What is the role of valves in the circulatory system?

To prevent backflow of blood, ensuring it flows in one direction.

What is the function of red blood cells?

To transport oxygen from the lungs to tissues.

What is the role of white blood cells?

To provide immunological protection by engulfing and destroying pathogens.

What is plasma?

The pale-yellow liquid portion of blood that transports proteins, nutrients, waste products, hormones, and antibodies.

What is the function of platelets in the blood?

To play a role in blood clotting.

What adaptations do red blood cells have for their function?

1. Biconcave shape for a large surface area to volume ratio 2. Small and flexible to squeeze through capillaries 3. No nucleus to maximize space for hemoglobin.

How do phagocytes adapt to their function?

1. Can change shape to engulf foreign material 2. Flexible membrane to squeeze through capillary walls 3. Contain enzymes to digest pathogens.

What are the two circuits in the double circulatory system of mammals?

1. Pulmonary circuit - deoxygenated blood goes to the lungs for gas exchange. 2. Systemic circuit - oxygenated blood is pumped to tissues and organs.

What happens in the pulmonary circuit?

Deoxygenated blood goes to the lungs where gas exchange occurs in the alveoli and capillaries.

What happens in the systemic circuit?

Oxygenated blood is pumped from the left side of the heart to the tissues and organs.

What is the structure of the heart?

The heart consists of chambers (atria and ventricles), valves (tricuspid, bicuspid, semilunar), and major blood vessels (vena cava, pulmonary artery, aorta).

What is cardiovascular disease (CVD)?

A group of diseases affecting the heart or blood vessels, often caused by atherosclerosis.

What are common risk factors for cardiovascular disease?

1. High blood pressure 2. High blood cholesterol 3. Smoking 4. Obesity 5. Lack of exercise 6. Poor diet 7. Family history and genetics.

What is atherosclerosis?

The buildup of fatty deposits (atheromas) on the walls of arteries, which reduces blood flow.

What is the role of the tricuspid valve?

To prevent backflow of blood from the right ventricle to the right atrium.

What is the role of the semilunar valve?

To prevent backflow of blood from the arteries into the ventricles after blood has been pumped out.

What is the difference between arteries and veins?

Arteries carry blood away from the heart under high pressure, while veins carry blood towards the heart under low pressure.

What is unique about pulmonary arteries and veins?

Pulmonary arteries carry deoxygenated blood from the heart to the lungs, while pulmonary veins carry oxygenated blood from the lungs to the heart.