What are Chromosomes? Science Worksheets for Kids

What are chromosomes? Chromosomes hold information in your body the way your phone holds the information for your favorite app or game. Chromosomes store the information in your cells that make you the person you are and instruct your body to work properly. What do chromosomes do? Where are chromosomes located? How many chromosomes do we have?

Great questions! Download our free, printable worksheets about chromosomes, and keep reading! If you have a young scientist at home, are a classroom teacher, or a homeschool parent looking for a science unit study, we are sharing lots of learning and teaching resources too!

Black and white model of a chromosome worksheet lying on top of a blue-green sheet with multicolored letters on a light gray background. — chromosomes store your body’s blueprints for your traits and how your body works.

What are Chromosomes?

To understand what a chromosome is, you also have to understand DNA. You’ve probably heard of DNA on television, in a book, or asked about it because someone said you looked like your mom or dad.

Okay, so what is DNA?

DNA is the molecule that lives in your cells and acts as a blueprint for you and your body. Hair color, eye color, freckles, you can do that weird rolly thing with your tongue, it all comes from your DNA. DNA is also responsible for things in your body you can’t see; like determining your blood type, and how your body reacts to medicine.

DNA has sections called genes. You have two copies of each gene, one from your mom and one from your dad. Those genes together are called base pairs – they determine who you are, what your body looks like, and how your body works.

DNA Definition: DNA is the molecule that carries genetic information about who you are and how your body works. DNA is shaped like a ladder that twists, this shape is called a double helix.

Need a refresher on atoms and molecules? You can read more here: What is an atom?

Now… What is a Chromosome?

Chromosomes are the storage facility for your body’s blueprints. And they live in nearly every cell in your body. Chromosomes are made from DNA and a type of protein. The protein wraps itself around the DNA so that it rolls up kind of like a spool of thread. In fact, if you look under a microscope, chromosomes actually look a little like thread. Chromosomes are located in the nucleus of almost every cell in your body.

If the chromosomes didn’t wrap around your DNA like that, your DNA would be about six feet long from one end to the other –> crazy, right?!

Chromosome Definition: Chromosomes are bundles of tightly coiled DNA located inside the nucleus of almost every cell in our body. Chromosomes store the information that makes us who we are and tells our body how to function.

model of a chromosome worksheet - a simple drawing of a chromosome with blank rectangles and a word bank for kids to add the right answer. coloring page for kids shown in black and white printed pdf version from Kids activities blog — Let’s learn the parts of a chromosome!

Chromosomes are threadlike structures made of protein and a single molecule of DNA that serve to carry the genomic information from cell to cell. In plants and animals (including humans), chromosomes reside in the nucleus of cells.

National Human Genome Research Institute

How Many Chromosomes Do We Have?

Humans have 23 pairs of chromosomes for a total of 46 chromosomes. One molecule of DNA and one protein make up one chromosome.

How many chromosomes do other living things have?

If humans have 23 pairs of chromosomes, how does that compare to animals or plants?

Are you surprised to find out your family dog has 39 pairs or 78 total chromosomes!?
A chicken has 39 pairs of chromosomes.
A banana has 11 pairs of chromosomes.

Science is cool. And weird. But mostly cool.

Science Terms about Chromosomes

Chromosome: is made up of protein and DNA, located in the nucleus of the cell.

DNA: is the code for all genetic traits located in the nucleus and organized in the chromosomes. DNA actually stands for Deoxyribonucleic Acid. –> Wow. That’s a mouthful.

Gene: is a segment or unit of DNA inside the chromosomes of living things.

Double Helix: the twisting ladder shape of DNA.

Base Pairs: gene pairs in the chromosome. One of the genes in the pair comes from your mom, and one from your dad. Together they determine your traits.

Traits: a characteristic of a living thing that is determined by the genes passed down through reproduction.

Heredity: how traits are passed down from parents to kids.

model of a chromosome coloring pages - a simple drawing of a chromosome with the answer of each part of the chromosome. coloring page for kids shown in black and white printed pdf version from Kids activities blog — Genes occur in pairs in the chromosome. One of the pair from your mom and the other from your dad.

Resources We Love About Chromosomes

I found the difference between chromosomes, DNA, and genes very confusing. (Just me? Sigh.) I knew they all played a role in heredity but I didn’t really understand how those things worked together until I was an adult.

The Amoeba Sisters is my absolute favorite YouTube Channel for explaining biology to those of us who are not actually scientists. If you need a crash course in heredity, this video is for you! The Amoeba Sisters are entertaining and a little silly, perfect for your budding scientist at home or in the classroom.

This video does a spectacular job of explaining how chromosomes contain genes that contain DNA that express traits that make you who you are. (Did you get all that?)

I really like this resource from Stated Clearly. This video is much lighter on entertainment but it is the simplest explanation I’ve seen about how proteins and DNA work to code for something in living things.

Need a little more help understanding DNA and how it works? Check out this lesson. It definitely gets into more details than we cover in this article. But the beginning is really helpful and straightforward.

DOWNLOAD PRINTABLE chromosome worksheet

Model of a Chromosome Worksheets

Science Resources and Learning Tools We love

This post contains some affiliate links.

Cool Science Experiment Alert: This one might need parent help but you can do it in your kitchen with things you already have on hand.

Yes, you can isolate DNA in your kitchen. MEL Science is the best gift ever for the science kids in your life. There was a point in time when we were getting 4 kits a month. Ahem… yes, 4 kits a month. We had to stop, not because we wanted to but because we were doing the MEL Science kits faster than they produced new ones.

I can’t tell you how many times I have gone back to Everything You Need to Ace Science for answers I either never learned (oops!) or don’t remember. For the purposes of this article about Chromosomes and DNA, see chapter 29. You’re welcome.

everything you need to ace science book cover

I tried to convince myself this is a teaching tool. The truth is, my science kid saw it in a science museum gift shop and freaked out. How do you not get your science kid a stuffed chromosome???

purple plush toy in the shape of a chromosome

Homeschool Curriculum and Science Enrichment about Chromosomes and DNA

Jenny Ballif, otherwise known as Science Mom, has a wonderful online course on Microbiology that covers cells in Unit 1 and biomolecules in Unit 2. DNA and chromosomes are covered really well in the second unit. The program is aimed at kids in middle school. But I had a kid in elementary that loved it and I learned a lot too. So I think there is a lot of potential even if you are outside of the advertised age range. (I also love the guided notes she provides with the course are in the form of cartoons.)

colorful covert art with microscope and background images of microscopic organisms

The DNA Book became part of our library this year. The content is great but I especially love the full-color photography. It really helps with complex concepts if you can actually see it!