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The Cell

The living things around us – plants and animals which inhabit every part of the world – differ from non-livingthings because they take in food, they grow andreproduce their kind. Animals andplants have several other activities which distinguish them from non-living things.

If we examine a very thin piece of a plant under a microscope, we'll see that it has a honeycomb structure; it is divided into a great many compartments called cells. Animal tissue, like plant tissue, is made up of cells and in large organisms the number of cells runs into many millions. In such organisms there are many types of cells; they differ in function and also in shape and size. Each cell is surrounded by a cell wall or membrane as it is generally called.

The cell walls of plants are formed of a substance called cellulose, which gives strength to the plant. Within the cell there is a thick jelly-like substance called protoplasm.

Protoplasm is the substance of which the living contents of the cell are composed. It is far more complex in its composition than cellulose, consisting of carbon, hydrogen, oxygen and nitrogen, and some other elements of which phosphorous and sulfur are the chief. It is soft and jelly-like in structure, never truly fluid. At times it is homogeneous and transparent, more often it is granular in appearance. There is always a quantity of water present, which, especially in the older cells, collects in drops or vacuoles. The protoplasm is the living part of the cell and possesses considerable power of movement.

In most living cells there is a nucleus, a rounded or oval structure embedded in the protoplasm. It plays an extremely important part in the life of the cell.

A B

To inhabit to be all around something

To distinguish to recognize the differences between things

To examine to live in a particular place

Compartment to look at something carefully

To surround to arrange the parts of something in order to get a particular effect

To compose one of the separate parts of the container or place where things are stored

Fluid to fix something firmly

Transparent the amount of something

Quantity likely to change

To possess thin enough for you to see things through

To embed to own something

Read the text make up its plan and do the assignment after it.

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