Introduction to Cardiovascular System

Cardiovascular system introduction

'Cardio' - Heart
'Vascular' - Veins/Arteries

The name cardiovascular tells us that this system includes the heart, blood, veins, and arteries.

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Cardiovascular

Multiple Select

The main goal of the cardiovascular system is to deliver blood to/from every living cell in your body.

Choose the substances that are delivered to each cell by blood.

• Hormones

• CO₂

• Wastes

• O₂

• H₂O

Multiple Select

The main goal of the cardiovascular system is to deliver blood to/from every living cell in your body.

Choose the substances that are taken away from each cell by blood.

• Hormones

• CO₂

• Wastes

• O₂

• H₂O

Arteries (red)
Capillaries
Veins (Blue)

• Arteries - They are tubes that lead blood away from the heart into capillaries

• Capillaries - Small tubes that carry blood to small places and back to the veins

• Veins - Veins return blood to the heart.

Both arteries and veins have layers that include endothelium, smooth muscle tissue, and a connective tissue coat; however, they have some differences. Most notable are the thicker walls of arteries and the presence of valves in veins. Thickened walls of arteries combat the pressure received from the pumping heart while valves prevent backflow when pushing blood back to the heart against the pull of gravity.

Veins vs. Arteries

Veins and arteries are larger near the heart. Blood leaves the heart with oxygen blood to deliver to the body through the aorta artery. Arteries become smaller and smaller until they become capillaries, the smallest blood vessel.

Capillaries then lead into small veins. Small veins lead to larger and larger veins as blood approaches the heart. Blood enters the heart from the superior and inferior vena cava where they enter the lungs. Oxygenated blood returns to the heart from the pulmonary veins. These vessels are the only veins that carry oxygenated blood.

Veins and arteries intersect at capillaries, a single cell thick, these are the thin epithelial cellular exchange areas.
Blood delivers hormones, oxygen, water, white blood cells, and nutrients​ to capillary exchange areas. Blood travels from arteries to capillaries.
Blood retrieves carbon dioxide and waste products. The wastes are delivered back to the heart through veins.

Capillary Exchange

Multiple Choice

Why do you need oxygen?

• To help you see in the dark
• To improve your memory
• To make you taller
• To facilitate cellular respiration and produce ATP

Multiple Choice

What type of tissue makes up the heart?

• Cardiac muscle tissue
• Skeletal muscle tissue
• Smooth muscle tissue
• Adipose tissue

The human heart is made of 4 chambers. To start, the heart is split into a left and right side using anatomical position. The top chambers of the heart are called atria. The bottom chambers of the heart that pump blood out are called ventricles.

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Heart Chambers

The Heart is a Double Pump

The heart receives oxygen-rich blood from the lungs that is pumped to the body from the left side of the heart.

At the same time, it receives de-oxygenated blood from the rest of the body and sends it to the lungs from the right side of the heart.

Poll

How many beats per minute (bpm) is the average human heartbeat?

• 72 bpm

• 55 bpm

• 110 bpm

• 128 bpm

To check your pulse, use your neck then place your index and third fingers on your neck beside your windpipe. To check your pulse at your wrist, place two fingers between the bone and the tendon over your radial artery. Count the number of beats in 15 seconds, then multiply by 4.
Using the ​

Pulse, Heart Rate

Open Ended

Who would have a slower average heart rate, a person with an active/athletic lifestyle or one with a sedentary lifestyle? Why?

Open Ended

When will you have a higher heart rate? When you are resting or when you are active? Why?

Hint: Cellular Respiration requires oxygen to create ATP.

Your blood is made of both cellular and liquid parts. The liquid portion of your blood is known as plasma. Plasma is 90% water and 10% proteins. White blood cells, also known as leukocytes, are the largest type of cell within our blood. They are also the least abundant type of cell in our blood. These large cells fight infection. Red blood cells, also known as erythrocytes, carry oxygen through our bloodstream. These 'oxygen-mailmen' are the most numerous cell in your blood. They are round, concave, and lack a nucleus. Without a nucleus, erythrocytes are not true cells. Platelets, or thrombocytes, are the smallest cells within your blood; however, they are also not true cells and are considered fragments. Platelets play a crucial role in hemostasis, or blood clotting.

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Blood

Multiple Choice

Which blood cell is most numerous?

• Leukocytes

• Thrombocytes

• Plasma
• Erythrocytes

Multiple Choice

Which blood cell is least numerous?

• Leukocytes

• Thrombocytes

• Plasma
• Erythrocytes