Page 496 - Canadian BC Science 9

6. If you do use colour, try to be as accurate as you can and choose colours that are as close as possible to the colours in the object you are observing.
7. Label your drawing carefully and completely, using lower-case (small) letters. Think about what you would need to know if you were looking at the object for the first time. Remember to place all your labels to the right of the drawing, if possible. Use a ruler to draw a horizontal line from the label to the part you are identifying. Make sure that none of your label lines cross.
8. Give your drawing a title. The drawing of a human skin cell shown below is from a student’s notebook. This student used stippling to show darker areas, horizontal label lines for the cell parts viewed, and a title—all elements of an excellent final drawing.
estimate the actual size of the object being viewed. Here are some steps to follow when making scale drawings of magnified objects. 1. Use a mathematical compass to draw an
accurate circle in your notebook. The size of the circle does not matter. The circle represents the microscope’s field of view.
2. Imagine the circle is divided into four equal sections (see the diagram below). Use a pencil and a ruler to draw these sections in your circle, as shown here.
3. Using low or medium power, locate an object under the microscope. Imagine that the field of view is also divided into four equal sections.
4. Observe how much of the field of view is taken up by the object. Note the location of the object in the field of view.
5. Draw the object in the circle. Position the object in about the same part of the circle as it appears in the field of view. Draw the object so that it takes up about the same amount of space within the circle as it takes up in the field of view, as shown in the diagram.
drawing made to scale (100x)
=
field of view under
the microscope (100x)
divided into four equal sections
The stippling on this drawing of a human skin cell shows that some areas are darker than others.
Drawing to Scale
When you draw objects seen through a microscope, the size of your drawing is important. Your drawing should be in proportion to the size of the object as the object appears when viewed through the microscope. This type of drawing is called a scale drawing. A scale drawing allows you to compare the sizes of different objects and to
Instant Practice—Scale Drawings
Design a scale drawing of your bedroom, using the shape of the floor rather than a circle like the example given above. Include scale drawings of the furniture in your room. When you are finished, label the fire escape routes.
478 MHR • Science Skill 6