What Makes a Reptile a Reptile?


Have you ever spotted a lizard sunbathing on a warm rock? Or maybe you have watched a turtle peek its head out of a pond. Lizards, snakes, turtles, and alligators might look very different from each other, but they all belong to the same animal group. They are all reptiles! Scientists group animals together when they share special features. So, what makes a reptile a reptile?
First, all reptiles are vertebrates. A vertebrate is an animal with a backbone. Just like humans, dogs, and birds, reptiles have a bony skeleton inside their bodies. This skeleton protects their organs and helps them move. Even a long snake, which can bend and twist into tight coils, has hundreds of tiny bones running down its spine.
Second, reptiles are cold-blooded. This does not mean their blood is always freezing cold! Instead, it means their bodies cannot make their own heat. When humans feel chilly, our bodies shiver and burn energy to warm up. Reptiles cannot do that. Their body temperature changes depending on the world around them. When a reptile feels cold, it crawls out into the bright sunshine to soak up heat. When it gets too hot, it creeps into the shade or digs a hole underground to cool down.
- vertebrates:
- Animals that have a backbone or spinal column inside their bodies.
- skeleton:
- The inner frame of bones that supports and protects an animal's body.
- cold-blooded:
- Having a body temperature that changes according to the temperature of the surroundings.
- keratin:
- A tough, protective protein that forms materials like scales, claws, and fingernails.
- predators:
- Animals that hunt and eat other animals to survive.
- reproduce:
- To create offspring or produce young of the same kind.
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About this explanatory article passage for Upper Elementary
“What Makes a Reptile a Reptile?” is a explanatory article reading passage about Reptiles, written for Upper Elementary. It takes about 3 minutes to read (445 words) and comes with an interactive quiz and a printable worksheet with comprehension questions and an answer key.


