Sunday, October 16, 2011


What are those things called CELLS anyways?

Cells are the starting point of all living organisms on Earth. Every living organism is made of millions and millions of cells.

Think about this later...
Some cells have a nucleus (Eukaryotes) and some do not (Prokaryotes). Plant and animal cells both have a nucleus inside, so they are sometimes known as Eukaryotic cells.

Plant cells-

Strong walls keep a cell from getting squished by neighboring cells.
Plant cells have a cell membrane AND and cell wall surrounding the inside stuff. The cell wall is made of rigid material called cellulose. Since plants don't have skeletons like most animals do, it's important that each plant cell has strong walls to support the other cells that neighbor it. This keeps the cell from getting squished by all of the other cells that make up a plant.
Plant cells also have a nucleus that is the control center of the cell. It controls everything that happens inside the cell. Cytoplasm -the inside stuff- surrounds the nucleus and other parts of the cell. Plant cells have chloroplasts inside which are responsible for the green color of plants and photosynthesis. In other words, chloroplasts are like the factory in the cell where sunlight is turned into food for the plant.

The chloroplasts are the green jelly-bean-looking objects in this picture.

Plant cells also have a vacuole. It is the storage area for the plant cell. Things that might get stored in the vacuole are waste products, water, and other materials that could be harmful to the cell. Vacuoles are sometimes like the garbage bin, taking care of waste products and sometimes like a refrigerator, storing food and water for the cell.

Plant cells look like this underneath the microscope...

Animal cells-

Animal cells are surrounded by cell membranes. Cell membranes separate the inside of the cell from the outside environment. They are like the orange skin that we peel off an orange. Cell membranes are selectively permeable, which means they can select what things may or may not enter the cell. Animal cells also have a nucleus. The nucleus is the control center of the entire cell. It controls what happens inside of the cell. 
The clear stuff around the yellow is like the cytoplasm in a cell...
 The cytoplasm is what surrounds the nucleus and other parts of the animal cell. Think of an egg you just cracked into a pan...The clear liquid stuff is sort of like the cytoplasm and the yellow yolk in the middle is like the nucleus. The cytoplasm in an animal cell is mostly made of water (about 90%).

Animal cells look like this under the microscope...

What do you notice about the two different kinds of cells?

Look at the shapes of each cell. The animal cell has a round shape and the plant cell has a rigid shape. Why do you think this is?...

How are these two cells alike?...

How are these two cells different?...

Which cell is more interesting: Plant Cell, Animal Cell, or Both cells? Why?...

Which cell is more important: Plant Cell, Animal Cell, or Both cells? Why?...

If you would like to find out more about plant and animal cells, visit some of these sites:
Cell Structure
Virtual Cell Tour
Teacher Tube Plant Animal Cell Video
Biology For Kids

The Basics of Cell Life With Max Axiom Super Scientist
Christina Examines Plant Cells and Animal Cells
Biology: Life As We Know It!