fbpx

KidsKonnect

Blood Vessels Facts & Worksheets

Blood Vessels are the pathways or channels through which blood can flow or pass

Search for Worksheets

Worksheets /Science /Blood Vessels Facts & Worksheets
Premium
Not ready to purchase a subscription? Click to download the free sample version   Download sample

How can blood travel all throughout the body? Are they just scattered or do they have a channel where they can flow? Blood, much like cars, also has pathways or channels where they can flow or pass. These channels are called blood vessels.

See the fact file below for more information on Blood Vessels, or you can download our 27-page Blood Vessels worksheet pack to utilize within the classroom or home environment.

Key Facts & Information

WHAT ARE BLOOD VESSELS?

  • Blood vessels are channels that transport blood throughout the body. It forms a closed circuit or loop that starts and ends in the heart. 
  • There are two closed circuits that begin and end in the heart- the systemic and pulmonary vessels.
  • The pulmonary vessels deliver blood from the right ventricle to the lungs and then to the left atrium. The systemic vessels deliver blood from the left ventricle to the different parts of the body and the back to the heart through the right atrium.
  • Blood vessels are very tiny but they cover almost all parts of the body. The size of a blood vessel range from 2 to 12 micrometers.
  • However, the largest blood vessel is about 2 centimeters wide. 
  • Despite their small size, if you take out all of your blood vessels, they will stretch for over 60,000 to 100,000 miles.

TYPES OF BLOOD VESSELS

  • There are three types of blood vessels: artery; vein; and capillary.
  • Arteries carry blood away from the heart while veins carry blood toward the heart. Then, we have the capillaries that form the connection between the arteries and veins.

ARTERIES

  • Arteries mostly carry oxygenated blood from the heart to the different parts of the body. But, did you know that there’s a set of arteries that carry deoxygenated blood? These are the pulmonary arteries.
  • Pulmonary arteries carry deoxygenated blood from the right ventricle to the lungs. Meanwhile, systemic arteries are the ones that carry oxygenated blood from the heart to the different parts of the body.
  • The ventricles of the heart are responsible for pumping blood away from the heart. Blood will be pumped by these chambers to large elastic arteries that branch out to smaller and smaller arteries. Microscopic arteries are called arterioles.
  • The walls of an artery have three layers: tunica externa; tunica media; and tunica interna.
  • Starting from the outermost layer, the tunica externa. This layer attaches the blood vessel to the tissues surrounding it. This layer is made up of connective tissues with collagenous and elastic fibers.
  • The middle layer is called the tunica media. This layer is mainly composed of smooth muscle tissues.
  • This is also the thickest layer of the arterial wall and responsible for providing support to the blood vessel. Aside from this, tunica media also changes the vessel diameter to help regulate blood flow and blood pressure.
  • Lastly, the innermost layer called the tunica interna, is made up of simple squamous epithelial cells and is surrounded by connective tissue with elastic fibers.

CAPILLARIES

  • The smallest type of blood vessel. This is responsible for connecting the arteries and veins. Also, its main function is to facilitate the exchange of material between the blood and cells. 
  • Thus, this type of blood vessel has the thinnest walls to allow diffusion to take place.
  • The distribution of capillaries throughout the body differs based on metabolic activities. 
  • Liver, kidney, and skeletal muscle tissues have an extensive capillary network as they are metabolically active and require a huge supply of oxygen and nutrients. 
  • While some have an abundant capillary network, some do not have a capillary network. Examples of these are the epidermis of the skin and the cornea of the eye.

VEINS

  • In contrast with the arteries’ function, veins mostly carry deoxygenated blood toward the heart except for pulmonary veins. These veins carry oxygenated blood from the lungs to the heart. 
  • After the blood passes through the capillaries, it will enter the smallest veins called venules. 
  • Blood will flow until it reaches the biggest veins, the inferior and superior vena cava, which will drain deoxygenated blood from the body to the right atrium. 
  • The walls of a vein are composed of the same layers that make up the walls of the artery. However, the walls of the vein contain a lesser amount of connective tissue, making it thinner than the arteries. 
  • This is also related to the fact that the blood flowing in the arteries has higher pressure while those flowing in the veins have lower pressure. 
  • Due to the structure and characteristics of the walls of the veins, they can hold more blood than the arteries. In fact, almost 70% of the blood is in the veins. 
  • Veins also contain a structure called valves which prevent the backflow of blood due to the pull of gravity. These venous valves are mainly found in medium to large veins.

BLOOD FLOW THROUGHOUT THE BODY

  • The blood vessels are the channels that transport blood thus, they also allow blood to flow throughout the body.
  • Let us begin the journey of the blood with the vena cava. Deoxygenated blood from the upper and lower parts of the body flows through the superior and inferior vena cava respectively. 
  • These two veins will drain the blood to the right atrium which then passes it to the right ventricle. 
  • The blood will then be pumped to the lungs and will pass through the pulmonary artery. 
  • Inside the lungs, oxygenation will take place. The air sacs, also called alveoli, are surrounded by capillaries. The exchange of gases between the alveoli and blood in capillaries will take place through diffusion. 
  • Blood will drop off carbon dioxide in the alveoli and will pick up oxygen, becoming oxygenated blood.
  • Oxygenated blood will be delivered to the left atrium of the heart via the pulmonary vein. 
  • The left atrium will pass the blood down to the left ventricle, which will then pump the blood to the largest artery of the body, the aorta.
  • The aorta will then pass the blood to the smaller arteries until it reaches the capillaries surrounding the different tissues of the body. Another gas exchange will take place as carbon dioxide will be picked up by the blood and oxygen will be dropped off. Then, the cycle repeats for as long as we are alive.

KEEPING YOUR BLOOD VESSELS HEALTHY

  • Blood vessels play a very important role in ensuring that an organism functions properly and efficiently. Thus, it is necessary to keep them healthy. However, there are a lot of disorders/diseases that affect the blood vessels. In the U.S.A.,  almost half of all adults have high blood pressure.
  • How can one prevent vascular disorders/diseases such as high blood pressure? Here are some tips on how you can prevent them.
  • Maintaining a healthy lifestyle is necessary to also keep our blood vessels healthy. Exercising and a healthy diet is necessary to avoid diseases such as atherosclerosis and high blood pressure.
  • Adding color to our diet is also essential. Fruits and vegetables in our diet add bioflavonoids which aid in circulation. Also, these foods are rich in fiber which can improve cholesterol and are also linked with artery and vein health.

Blood Vessels Worksheets

This is a fantastic bundle that includes everything you need to know about Blood Vessels across 27 in-depth pages. These are ready-to-use worksheets that are perfect for teaching kids about Blood Vessels, the pathways or channels through which blood can flow or pass.

Complete List of Included Worksheets

Below is a list of all the worksheets included in this document.

  1. Blood Vessels Fact File
  2. Crossword
  3. Fact Check
  4. Self-Check
  5. A-V-C
  6. Essential To Life
  7. Cause and Effect
  8. Vascular Health
  9. Run For Your Life
  10. World Hypertension Day
  11. Comic Strip

Frequently Asked Questions

How long are human blood vessels?

The human body has about 650,000 miles of blood vessels. If you took all of the blood vessels out of a person and put them in a line, the line would be 60,000 kilometers long. An adult might be 100,000 kilometers long. Blood vessels are divided into three categories: arteries, veins, and capillaries.

What do the blood vessels do?

The vessels in your body keep the blood flowing. This is important because it supplies your tissues with oxygen and nutrients. It also helps keep your organs healthy, including your heart. In embryos, specialized cells form the lining of blood vessels. Other cells build up into the layers of these vessels.

Do blood vessels grow back?

Over time, damage to the bloodstream’s vessel lining- called the endothelial lining- occurs from regular wear and tear. Nevertheless, our bodies have developed a way of regenerating this molecular activity so it can repair itself.

Link/cite this page

If you reference any of the content on this page on your own website, please use the code below to cite this page as the original source.

Link will appear as Blood Vessels Facts & Worksheets: https://kidskonnect.com - KidsKonnect, October 8, 2022

Use With Any Curriculum

These worksheets have been specifically designed for use with any international curriculum. You can use these worksheets as-is, or edit them using Google Slides to make them more specific to your own student ability levels and curriculum standards.

Related Resources