Circulatory System

Circulatory System Red blood cells carry oxygen from your lungs to every cell in your body. Your blood also transports several other nutrients and waste products throughout the body.

What colour is an rbc? They are red if they are carrying O2. They are bluish-purple if they are not carrying O2. Each red blood cell has a millions of special proteins called hemoglobin. Each hemoglobin allows 4 oxygen molecules to bond to it. Hemoglobin is composed of iron.

Why is blood red? When hemoglobin binds to oxygen, it oxidizes the iron within the hemoglobin. This is the same principle as iron rusting.

Do you have one of these? Why should you have a carbon monoxide detector, and what does it have to do with blood?

Review from Term 1 Where do red blood cells form? Red blood cells only live for approximately 120 days. When they die, they are broken down and ingested by white blood cells.

What is erythropoietin? This is a hormone that promotes the production of red blood cells. It exists naturally in your body. What would happen if you ingested yourself with erythropoietin?

Blood Doping

What’s good for your circulation? Your heart pumps blood everywhere it needs to go in the body. If it has a difficult time forcing blood through its vessels, it will work harder. This is bad!

How the heart works When your heart is filled with blood, it pumps it out. This is like squeezing water out of a water balloon. When the blood is fired out of your heart, it exerts the highest amount of pressure on your blood vessel walls. At the same time, the heart reloads with blood for its next heartbeat. While it reloads, the blood exerts the minimum amount of pressure on your blood vessel walls.

Blood Pressure When the heart pumps, the pressure is maximized. This is called systole. When the heart reloads (relaxes), the pressure is minimized. This is called diastole.

Measuring blood pressure This is done with a sphygmomanometer.

When the pressure drops, you can HEAR blood forcing through the artery with a stethoscope (Systolic) When you HEAR NOTHING, it means blood is flowing easily with no resistance in the arteries. (Diastolic)

Hypertension High blood pressure is known as hypertension. Hypertension risks: Heart failure (if your heart does not get enough oxygen) Stroke (if your brain does not get enough oxygen)

What causes hypertension? https://www.youtube.com/watch?v=Ab9OZsDECZw