Lab Drawings

Drawing is a very important skill in biology and is considered a type of data collection because drawings help to record data from specimens. Drawings can highlight the important features of a specimen.   A drawing is the result of a long period of observation at different depths of focus and at different magnifications.   

Drawing Materials:  All drawings should be done with a sharp pencil line on white, unlined paper.  Diagrams in pen are unacceptable because they cannot be corrected.  

Positioning:  Center drawing on the page.  Do not draw in a corner.  This will leave plenty of room for the addition of labels.

Size:  Make a large, clear drawing; it should occupy at least half a page.

Labels:  Use a ruler to draw straight, horizontal lines.  The labels should form a vertical list.  All labels should be printed (not cursive).

Technique:  Lines are clear and not smudged. Avoid ‘feathery’ pencil lines and gaps.  There are almost no erasures or stray marks on the paper. Color is used carefully to enhance the drawing. Stippling is used instead of shading.

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Accuracy:  Draw what is seen; not what should be there.  Avoid making “idealized”drawings.  Do not necessarily draw everything that is seen in the field of view.  Draw only what is asked for. Show only as much as necessary for an understanding of the structure – a small section shown in detail will often suffice.  It is time consuming and unnecessary, for example, to reproduce accurately the entire contents of a microscopic field. When drawing low power plans do not draw individual cells. Show only the distribution of tissues. When making high power drawings, draw only a few representative cells; indicate thickness of walls, membranes, etc.

Title:  The title should state what has been drawn and what lens power it was drawn under (for example, phrased as:  drawn as seen through 400X magnification).  Title is informative, centered, and larger than other text. The title should always include the scientific name (which is italicized or underlined).

Scale:  Include how many times larger the drawing is compared to life size and a scale line that indicates relative size.  To determine magnification, use the equation:

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For additional information, see the Drawing Skills Handbook or Steps to Success.