3.51 Blood Facts

Explore the interesting world of blood and discover some facts about blood. Explore the components of blood and what each part does, investigate the process the body uses to make blood, and finally, learn about different blood types.

What Is Blood Made Of?

If you have ever scraped your knee, you have seen blood up close. But what exactly is that red liquid? Where does it come from? The thought of blood might gross you out, but blood has many important jobs in our bodies: it delivers oxygen, helps get rid of waste and helps us fight infections.

How are a bowl of chicken noodle soup and blood alike? Both soup and blood are made of liquid and solid ingredients.

Chicken noodle soup is made of broth, the liquid part you slurp off your spoon, and solid noodles. Your blood is made of a liquid called plasma and three different types of cells. Each ingredient in your blood does a special job.

Check out this diagram:

In this up close view of blood, you can see its main ingredients: plasma, red blood cells, white blood cells and platelets. The solid cells are floating in the liquid plasma.
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1. Main points:

Blood is a vital fluid in our bodies that performs important functions like delivering oxygen, removing waste, and fighting infections. It consists of plasma and three types of cells: red blood cells, white blood cells, and platelets.

2. Questions:

• Content Analysis: What are the main components of blood and what do they do?
• Contextual Analysis: Why is the comparison made between chicken noodle soup and blood in the text?
• Linguistic Analysis: How does the text describe the function of blood in a way that is easy for kids to understand?

3. Further Discussion:

• If you could be one component of blood, which would you choose and why?

4. Answers:

• Content Analysis: "Your blood is made of a liquid called plasma and three different types of cells."
• Contextual Analysis: "How are a bowl of chicken noodle soup and blood alike? Both soup and blood are made of liquid and solid ingredients."
• Linguistic Analysis: The text uses simple comparisons like "Chicken noodle soup is made of broth, the liquid part you slurp off your spoon, and solid noodles. Your blood is made of a liquid called plasma and three different types of cells." to explain the function of blood.

Plasma

Over half of blood is made of a yellow liquid called plasma. Plasma transports things, like nutrients and proteins, throughout the body. Plasma also works like a garbage truck because it carries away waste made by the cells in your body.

Red Blood Cells

Red blood cells are the most common type of cell found in your blood. Their main job is to carry oxygen to all of the other cells in your body, from your head to your toes.

White Blood Cells

Did you know that your blood has an army of germ fighters? White blood cells help protect your body from infection by attacking and killing germs.

Platelets

The smallest cells that make up your blood are called platelets. Platelets are sticky little cells that work like bandages. If a blood vessel is broken, like when you cut yourself, platelets stick to the break to stop the bleeding and fix the broken vessel.

1. Main points:

Blood consists of plasma, red blood cells, white blood cells, and platelets, each performing unique and crucial functions like transporting nutrients, carrying oxygen, fighting infections, and aiding in blood clotting.

2. Questions:

• Content Analysis: What are the specific functions of each component of blood?
• Contextual Analysis: How does the text explain the importance of each blood component in a way that is relatable to everyday experiences?
• Linguistic Analysis: What language techniques does the text use to make the information about blood components engaging for kids?

3. Further Discussion:

• If you could see these blood components under a microscope, what do you think they would look like and why?

4. Answers:

• Content Analysis: "Plasma transports things, like nutrients and proteins… Red blood cells… carry oxygen… White blood cells help protect your body from infection… Platelets… stop the bleeding and fix the broken vessel."
• Contextual Analysis: The text relates plasma to a "garbage truck" and platelets to "bandages," making the functions of these components understandable through familiar objects.
• Linguistic Analysis: The text uses analogies and simple, vivid descriptions, like plasma working like a "garbage truck" and platelets being "sticky little cells" that act like "bandages," to engage kids’ interest and understanding.

How Is Blood Made?

Red blood cells, white blood cells, platelets, plasma, oh my! Blood sure has a lot of different parts. Your body makes all of these parts, so you could say you are a blood-making machine!

The solid parts of blood – red blood cells, white blood cells and plasma – are made by your bone marrow, the tissue in the middle of your bones. Plasma is mostly made of water, which your intestines absorb from the stuff you eat and drink.

Types of Blood

Not everyone’s blood is exactly the same. There are four main types of blood. The letters A, B and O are used to describe blood types. Each letter stands for the type of protein found on a person’s red blood cells.

People that only have A proteins on their cells have type A blood, while people with only B proteins have type B blood. People with both A and B proteins have type AB blood.

Some people do not have any proteins on their red blood cells. These people have type O blood. This is easy to remember because an O looks like a zero and these people have zero proteins!

Blood Facts

Let’s wrap up by taking a look at a couple of interesting facts about blood.

• The average person has 1 and ½ gallons of blood in their body.
• It takes less than one minute for your blood to travel throughout your entire body.
• Not all blood is red. Earthworms have green blood and crabs have blue blood!

1. Main points:

Blood is composed of various parts produced by the body, including red and white blood cells, platelets, and plasma. There are four main blood types determined by specific proteins on red blood cells. Interesting facts about blood include its quantity in the human body and its different colors in other species.

2. Questions:

• Content Analysis: What are the four main blood types and how are they determined?
• Contextual Analysis: How does the text make the concept of blood types easier to understand for kids?
• Linguistic Analysis: What language techniques does the text use to engage young readers in learning about blood?

3. Further Discussion:

• Why do you think different creatures, like earthworms and crabs, have different colored blood?

4. Answers:

• Content Analysis: "The letters A, B and O are used to describe blood types. Each letter stands for the type of protein found on a person’s red blood cells."
• Contextual Analysis: The text uses a simple analogy, "an O looks like a zero and these people have zero proteins," to explain type O blood in an easy-to-remember way.
• Linguistic Analysis: The text employs engaging language and relatable analogies, like comparing the O in type O blood to zero, to make the concept of blood types interesting and memorable for kids.

Lesson Summary

Blood is made of plasma, red blood cells, white blood cells and platelets.

• Plasma transports things, like nutrients and proteins, throughout the body.
• Red blood cells carry oxygen throughout your body.
• White blood cells protect your body from germs.
• Platelets are sticky little cells that work like bandages. There are four main types of blood: type A, type B, type AB and type O.