A Tool to Breathe Human skin and animal skin are similar in some ways. T ey are diff erent in others. Here’s one more way they’re diff erent. Frogs and other amphibians breathe through their skin. T at’s right. T eir skin is so thin that gases can pass through it. Oxygen moves into the body. Carbon dioxide moves out. Most amphibians also have lungs for


breathing. Yet these are oſt en not well developed. So when a frog chases aſt er an insect, it uses both lungs and skin for breathing. Humans can’t use their skin to breathe. Yet


think about some of the incredible ways this organ helps you. It protects you, controls your temperature, and gives you your sense of touch. We owe a lot to the skin we’re in.


Wordwise


cell: the smallest living part of an animal or plant


dermis: the middle layer of skin epidermis: the top layer of skin hypodermis: the bottom layer of skin


organ: a part of the body that does a specifi c job


skin: the body’s outer covering and largest organ


A pattern on this boa constrictor’s skin helps it hide in its environment.


This chameleon changes the color of its skin to communicate.


Skin Deep


Some animals use skin in different ways than we do.


Skin coated in slime protects this sea slug against predators.


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