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    Answer 6 out of 8 questions correctly.

Your body is a complex and organized system. It is made up of many smaller and simpler systems, including
cells.
An image of a human embryo
Early on, a human is a small number of unspecialized cells.
Humans are multicellular, or made up of more than one cell. In fact, an adult human body has about 37 trillion cells.
Like other multicellular organisms, a human starts as a single cell. That first cell grows and then divides to form more cells.
As a human body grows, it develops many types of specialized cells. Specialized cells have specific functions as well as specific structures that help carry out those functions. Different types of cells in the human body include skin cells, muscle cells, and blood cells. Together, all types of cells carry out the functions that the body needs to survive.
Click the blue words to correct the statement.

As multicellular organisms grow into adults, they become larger and less complex. They develop many types of specialized cells, which have the same structures and functions.

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