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## Form 3 Biology - Order This CD Today

Quadrat.

A quadrat is a square of a wooden or metallic frame of a known area. It can be 1square metre, 0.5square metre or any area.It is made by joining four pieces of wood/metal together.

The following are the steps followed when using a quadrat.

• Identify a selected area
• Toss the quadrat over the shoulder in the selected area
• Make a table with rows indicating the number of throws while the columns have the titles to show results after every throw.
• Count the number of the organism of interest and record.Sometimes it is impossible to say where one plant stops and another begins. In this case use a percentage area of the quadrat covered.
• Repeat the above procedure for at least four times for a good sampling
• Add the total number of all the values of organism obtained and divide by the number of throws done to get an estimate of the population.

Play the video below to see secondary school students estimating population using the quadrat method.