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Transcript
CELLS AND THEIR ENVIRONMENT: Homeostasis and Diffusion HOMEOSTASIS and diffusion LIFE’S BALANCING ACT When we are too cold we shiver, it warms us up. When we are too hot we sweat, it cools us down. Your body is made up of cells. And, just like your body, cells must stay balanced too. They must have just the right amount of materials to maintain the proper environment for your body. HOMEOSTASIS The balance that all living things have to maintain is called HOMEOSTASIS. Everything we eat and drink is made of small particles called molecules. These particles are always moving around and bumping into each other. They will move from areas that are crowded to areas that are less crowded until they spread out evenly. The movement of particles in our cells from areas that are more crowded to areas that are less crowded is called DIFFUSION. mmore crowded less crowded Diffusion happens in cells. nucleus ???? mitochondria ???? cytoplasm ???? Cell membrane ???? Remember the cell? How many of these parts do you remember? This is a cell membrane. Can you find the parts where particles might go in and out of the cell? Click to check your answer. This is one of five channels in the diagram that moves particles in and out of the cell. The cell membrane is like the doors of a school. It has special entryways that allow particles to move into and out of the cell. Like in the cell membrane, students only go into and out of school through the doors. Students are like the particles in cellular diffusion. They move from the crowded buses into the school through the doors. Once inside, they spread out relatively evenly into their classrooms.