Drawings for laboratory reports
What makes a good drawing
Here
is a good drawing of an Amoeba proteus cell drawn live. This
image is slightly less than full size.

What
makes this drawing good. Accuracy; it actually looks like the specimen.
Anyone can recognize it. all major parts of the organism are clearly and
ccurately portrayed. The major parts of the cell are clearly labeled.
Notice that not all of the detail is shown. The finer details are filled
in in only part of the drawing. This is OK. There is enough to
give the viewer a good idea of the appearance of the cell. As this was
an observation on a living specimen, it is important that patterns of
movement are noted. This could have been done a bit more clearly, for
example, indicating the pattern of cytoplasm out of the uroid portion
of the cell, as well as the patern of flow in the oldest of the pseudopodia.
Notice
the use of lables and marginal notes. These are important.
Why
was the mark on this drawing 8.5 and not higher? The contractile vacuole
was plainly visible in these specimens and was missed. It is usually located
in the region between the nucleus and the uroid. As mentioned bove, the
pattern of cytoplasmic movement might have been dealt with in a more complete
manner.
For
comparison, here is another drawing, below, of the same species that is
not so good. This drawing lacks detail. A good point is the indication
of the direction of cytoplasm movement. The designation of the nucleus
is incorrect. This is close to the minimum acceptable standard s you can
tell by the mark assigned. The mark is as high as it is because the labeling
is largely correct. It is not particularly clear what the student saw,
or that it was interpreted correctly.

What
is the difference? The difference in is realism, clarity and accuracy.
Notice that the mark for this drawing is not a 5. There are some good
features. It is relatively carefully done. The lines are clear and firm,
structures are labeled, even if wrong, curves are closed. While not particularly
good, this work is not careless or slipshod. There is clearly some observation
behind it, as well as a fair amount of care in its execution.
The
following pair of drawings are of a stained Arcella specimen.
The dark granular material in the drawing below is the chromidial net,
a massive construction of rough endoplasmic reticulum that is involved
in synthesis of proteins to form the text for the next generation. The
two round bodies with dark centres are nuclei.

This
drawing above is really quite good. The nuclei, coromidial net and the
test are well drawn. Notice, however that the nuclei and the endosome
within the nucleus is not labeled. The chromidial net and the test are
properly labeled. Better labeling would have resulted in a higher mark
for this drawing

This
drawing is not as good. The labeling is potentially better than in the
drawing above, but some of the structures are improperly interpreted (e.g.
secretory granules). The drawing lacks detail and is not particlarly easy
to interpret. As you can see this was given a mark of 7/10.
Below
we have a well labeled drawing of Acanthamoeba.

Here
is another drawing of a different specimen of Acanthamoeba. This
drawing would win no prise for artistic merit. That is, however, only
a secondary issue. It is basically correct and is correctly labeled, even
though it lacks detail.
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