True Book: Your Amazing Body

Discover the main systems of our amazing human body with this new series of books! Our muscular system covers our bodies from head to toe. It helps keep us upright and gives us the power to stand, sit, run, smile, and more. Did you know that your muscles make up one-third of your body weight? Or that your tongue is made up of eight separate muscles? Learn all this and more in Muscular System.

Discover the main systems of our amazing human body with this new series of books! Our respiratory system is responsible for cleaning the air that we breathe, supplying our bodies with oxygen, and getting rid of carbon dioxide. Did you know that you breathe in and out about 22,000 times a day? Or that your left lung is slightly smaller than your right? That leaves room in your chest for your heart! Learn all this and more in Respiratory System.

Discover the main systems of our amazing human body with this new series of books! Digestion starts the minute you put food or a drink in your mouth. And by the time the process ends, your body has taken every bit of nutrition possible from your food. Did you know that the average person produces enough saliva in one year to fill a bathtub? Or that the small intestine is the longest part of the digestive system? Learn all this and more in Digestive System.

Discover the main systems of our amazing human body with this new series of books! The blood that flows through your body constantly brings food and oxygen to your muscles, organs, and bones and carries away waste. And it is all powered by that magnificent muscle, your heart. Did you know that your heart beats about 100,000 times a day? Or that the blood in your body travels a total of 12,000 miles daily? That's more than four times the width of the United States from coast to coast! Learn all this and more in Circulatory System.

Discover the main systems of our amazing human body with this new series of books! The human brain is a natural wonder-the command center that, through a network of nerves, runs every other system in our bodies. Did you know that there are 100,000,000,000 neurons in your brain? Or that your funny bone is actually a nerve in the elbow, not a bone? Learn all this and more in Nervous System.