The heart is divided into four chambers. The upper chambers are referred to as atria and the lower chambers are referred to as ventricles. The septum consists of a thick wall of tissue that separates the right and left sides of the heart.

Red blood cells play an important role in carrying oxygen and carbon dioxide throughout the body.

Air flows through the trachea, which branches into the bronchial tubes, which lead to the lungs. The lungs are made of millions of balloon-like structures called alveoli, which are surrounded by capillaries.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "The In Crowd" by Dobie Gray.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Get It On" by T Rex.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Everybody Wants To Rule the World" by Tears for Fears.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Earth Angel" by the Crew Cuts.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Many Rivers To Cross" by Jimmy Cliff.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "It Don't Mean a Thing If It Ain't Got That Swing" by the Mills Brothers.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Midnight Hour" by the Commitments.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "It's a Kind of Magic" by Queen.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "You Couldn't Be Cuter" by Al Bowlli.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Stand by Me" by Ben E. King.

Exquisite animal footage filmed around the globe and classic pop tunes combine to create a series of short educational and entertaining programs that will grab and hold students attention while leading them toward an understanding of animals, their behavior, and their habitats. Featured song: "Mio Rambino Carro" by Puccini.