Comprehension Activities

Donuts and sprinkles to understand blood types: https://www.lifeblood.com.au/news-and-stories/trending-research/blood-types-and-doughnuts
CBC Cookies: https://video.link/w/XSLvd
Blood Model in a Jar: https://www.myjoyfilledlife.com/components-blood-activity-kids/
Operation Ouch—What is Blood Made of?: https://video.link/w/wSLvd
A Drop of Blood book: https://www.harpercollins.com.au/9780060091101/a-drop-of-blood/
A Drop of Blood read aloud on video, with hilarious vampire voice: https://video.link/w/cULvd


Some people faint at the sight of it, but we couldn’t live without it! This is your Squiz Kids Shortcut to blood—the podcast where we dive into the who, what, when, where, why and how of the big news stories. I’m Amanda Bower.

And I’m Bryce Corbett.

Bryce, I heard an amazing fact the other day. Over our lifetimes, one in three Australians will need to be receive blood as part of medical treatment… but only one in 30 Australians donates blood!

With World Blood Donor Day coming up on June 14, we thought it was a good time to take you through WHAT exactly blood is; WHY doctors test your blood when you’re sick; and HOW you can have fun learning about blood.

Listen carefully – there’s a Squiz at the end!

Bryce, I like to think of blood as the body’s public transportation system. You have a whole network of blood vessels—kind of like underground train tunnels—and the blood travels through them, dropping off and picking up passengers along the way. It takes things like oxygen, nutrients, cells, and hormones where they need to go… and it transports carbon dioxide and other waste products away.

Nice metaphor. Now, the heart is kind of the engine room of this transport system, pumping the blood around your body.

Ooh, way to extend the metaphor! Nice one. Yes, the average adult’s heart is responsible for constantly moving just under 5 litres of blood around the body. For a kid weighing 35 kilos, it’s about two-and-a-half litres.

And what IS blood, exactly?

It’s made up of four things: plasma, and three kinds of blood cells

Plasma like a plasma screen TV?

No… In primary school you often learn that there are three states of matter: liquid, gas, and solid. But there’s actually a fourth: plasma. It’s a charged gas with special properties, and you’ll get to it in highschool. The plasma in TVs and other tech products is that kind. The stuff in your blood is a liquid, mostly made up of water. It transports hormones, vitamins, and more around our bodies, and it also contains proteins that fight infections and help our blood to clot.

And then there are three different kinds of blood cells in that plasma?

Exactly right. Red blood cells are the reason our blood is red. Their job is to carry oxygen throughout our body, and then take carbon dioxide away. Then we have white blood cells. They lead the charge in fighting infection in our bodies. Most of our white blood cells are actually in other parts of our body, so if we have a lot in our blood, it’s a sign that our body’s really struggling against a disease. Finally, we have platelets. They’re much smaller than the other blood cells, and their job is to make the blood clot when we get a cut, and stop us from losing blood. They basically clump together to form a plug.

So it’s platelets we have to thank when we get a little cut and it stops bleeding. Now Amanda, sometimes when you’re sick, the doctor will take a little bit of blood to run tests on it. WHY is that?

Bryce, have you ever watched a medical show where they say “Get me a CBC, Chem 7, stat!”

I’ve always wondered what that meant!

CBC stands for complete blood count. They’re looking at how many of the three different blood cells are in your blood. If there are extra white blood cells, you could be fighting an infection. There are also some diseases of the blood that will show up on your CBC results. Chem 7 looks at the amount of 7 different substances in your blood. We’re not in medical school yet, so I’m not going to go into all of them, but they’ll give doctors information that could help them diagnose all kinds of diseases. But Bryce, doctors don’t just test our blood when we’re sick… they also do it when women are pregnant.

Oh yeah… I remember that. Why is it again?

They’re testing to see what blood TYPE the biological mother and father are. It’s not a problem if they’re different, but they may need to give a medicine to the mum.

How many blood types are there?

There are 4 main blood groups—A, B, AB and O. Now, we don’t have time here to go into why that is, but the Red Cross has a completely excellent deep dive into this, explaining blood types with the help of donuts and sugar sprinkles. My kind of teaching. I’ll put a link in your episode notes!

The blood group you belong to is determined by the genes you inherit from your parents.

That’s right. And each of those four groups can then be something called Rhesus factor positive or negative, which the donuts and sprinkles explain in more detail.

That means in total there are 8 blood groups… and I believe, Amanda, that the Red Cross is especially excited about your blood type.

Yep, I’m O negative, and they are very happy when I come in for the free snacks in return for a bit of blood. Sorry, Squiz Kids… you have to be over 18 to get those snacks… I mean, donate life-saving blood.

You’re funny. Speaking of fun, HOW on earth can kids have fun learning more about blood?

This is where I get to put my teacher hat on and share a bunch of fun experiments and resources. Obviously, most kids are not going to want to make a hole in their skin just to watch the blood leak out. But you can look at your blood without getting hurt! Bryce, you’re going to need a torch…

Got it.

Now go into a dark place with the door shut, and stick the torch in one of three places. Most fun – but only if the torch isn’t for sharing – is inside your mouth, with the light shining through your cheek. But you can also put it behind your ear, or up against your fingers. What colour is the light that’s coming through your body?

I’m not going to give it away… but coooool…

I’ve also put links in your episode notes to a recipe for cookies that represent those seven things measured in a Chem 7… another link showing a way to make a model of blood in a glass jar that involves jelly beans, marshmallows, and sprinkles … and a video about blood from the “Operation Ouch” team

Oh, I love them! Twin doctors who make videos about all the important medical stuff… like what would happen if you never brushed your teeth…

And one on lighting farts on fire. They are definitely a kid-friendly educational outfit! And Bryce for my final trick, I’ve put in a link to a fabulous book with a vampire narrator, called “A Drop of Blood”.

I can’t wait to take a bite out of that.

I see what you did there.

The S’Quiz
This is the part of the podcast where you get to test how well you’ve been listening…
1.Which blood cells are responsible for the colour of our blood?
2. If you scrape your knee, which type of blood cell helps the bleeding to stop?
3. What dessert can be used to explain blood types?