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Today we are going to learn about what happens inside cells. We're also going to talk about how to visualize cells and practice comparing and contrasting parts of a cell.



What is happening here? What changes are taking place? Where could something like this be happening inside you?

Cells have special parts called organelles. Each part has a job to do. All cells can make exact copies of themselves through cell division. Does this remind you of the picture we looked at earlier?

= Jobs of a Cell = Cells do work that keeps you alive. They provide energy and help you grow, reproduce, and fight off sickness.

Cells provide energy by taking in nutrients that carry energy.

Cells multiply and help you grow.

Cells make copies of themselves. Every living thing reproduces through it's cells.

Cells help fight infection. Most of your cells have special jobs. One job is to stop sickness by attacking germs.

Part 2:

= Making New Cells = Every day your cells make new cells - billions of them!

Whenever your body needs new cells, a parent cell divides itself into two, making an exact copy of itself. The new cells are called daughter cells. Each daughter cell can become a parent cell.

Cells have a cycle. They are born, live, and work as a single cell. At the end of their cycle, they divide. Some cells divide once a day, others divide much less. The nucleus of the cell tells it when to stop dividing.



A cell's nucleus contains it's chromosomes (structures in the nucleus that contain information). This information gets passed off to the daughter cells. As the cells divide into two, the chromosomes make copies of themselves. There are then two sets of chromosomes. One set goes into each new cell.

Mitosis - the set of stages in division of the cell nucleus



You, like all living things, grow because your cells constantly divide. New cells replace old cells that have died. New cells also help you grow bigger and taller. Cell division helps you grow and stay healthy.

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