Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
What Is a Tissue? What Is a Tissue? Close your eyes and picture your school. It is probably a building with many different rooms. Each room has a special use. You eat in the cafeteria. You read books in the library. Together, all the separate rooms make up your school. A multicellular living thing is set up in a similar way. Multicellular living things are made of many cells. All people, plants, and animals are multicellular living things. They can have many different types of cells. Different types of cells look different and have different jobs. For example, the cells in your skin look different from the cells in your brain. The cells in your skin help protect your body, and the cells in your brain help you think. Cells of the same type group together to form tissues. You have different tissues in different parts of your body. Like the rooms in your school, each tissue has a special use. For example, in your body, special muscle cells group together to form heart tissue. Heart tissue helps the heart pump blood around your body. Although you have different types of tissues in your body, they can work together. Tissues that work together to do a job are part of a system. Complex living things have many different systems. Each system has a certain job. The heart tissue in your body works with tissues in the arteries, veins, and blood. Together, these tissues make up your circulatory system. The circulatory system brings blood to all parts of your body. You are a complex living thing. All your systems work together to keep you alive. Humans are complex, multicellular living things. Even your blood is made up of many different types of cells. Discovery Education Science © 2007 Discovery Communications, LLC Page 1 of 2 What Is a Tissue? Not all multicellular living things are complex. Sponges are simple multicellular animals that live in the ocean. They are made of only a few different types of cells. Each type of cell forms a tissue within the sponge. The cells in each tissue work together to do a job. The tissues work together to keep the sponge alive and healthy. A sponge is a simple multicellular living thing. Its tissues work together to help it take in food and survive. Discovery Education Science © 2007 Discovery Communications, LLC Page 2 of 2