The Heart
The heart is an incredible organ. In vertebrates, it is a hollow muscular organ that pumps...
What kind of baby weighs 400 pounds and is eight feet long? This giant bundle of joy belongs to an orca. An orca is a type of whale. Baby orcas are amazing creatures. Soon after they are born, they can swim on their own. They live in all the oceans in the world. But they are most common in the Antarctic and Arctic oceans. When orcas grow up, they weigh 3,000 to 8,000 pounds. The fins on their backs can grow to be six feet tall. Because these whales are so big, they have no enemies in the natural world. People are the only thing that can threaten them. Orcas need 500 pounds of food a day. They eat just about everything, including fish, penguins, squid, and turtles. They even eat other whales. This is why they are also called killer whales.
The heart is an incredible organ. In vertebrates, it is a hollow muscular organ that pumps...
The earth's surface is composed of big slabs of rock called plates. Volcanoes are form...
The blue whale is the biggest animal that has ever lived on Earth. It is bigger than any d...