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okay so there should be a pretty quick
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video here kind of the basics of
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microscope drawings you know what's
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expected and maybe some of the errors
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that we can try to avoid along the way
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so let's get started okay so here's our
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microscope and we're gonna select to get
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started the lowest magnification
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possible the lowest power objective lens
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and we'll look through the eyepiece of
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course and when we do we're gonna see a
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round view this is what's called our
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field of view it's the view that you can
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actually see when you're examining the
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specimen now pretend we're looking at
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these cells right here these were cells
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taken from an onion skin an onion peel
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well now we have some needs to address
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so the first need I want to address is a
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title tell the viewer of your drawing
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your observation what the specimen is
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what are you actually looking at the
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next would be what is the total
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magnification of the microscope remember
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science is repeatable and if you have a
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really interesting observation that you
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are sharing the only way you're going to
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be able to repeat it is if you address
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what the total magnification of the
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microscope is well then we have to do
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our drawing an accurate depiction an
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accurate drawing of what you're able to
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see and then finally we can add some
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labels some identifying characteristics
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to help point out what it is we are
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observing well let's get ready to do our
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drawing here's our blank field of view
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that we're gonna assume draw in and our
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first decision is should we use a pen or
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a pencil now this should be an easy
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answer I hope we're gonna do a drawing
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there is a high probability of making a
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let's go ahead and select the pencil
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it's cleaner if you do make a mistake it
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erases better so we're gonna use a
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pencil now the first thing is let's
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select the title how about microscope
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drawing after all we're making a
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microscope drawing I hope you realize
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maybe cells cells for a title after all
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these ourselves again too vague be
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specific tell the viewer what it is
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you're looking at cells taken from an
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okay so next I'm gonna focus on the
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magnification now earlier I said we're
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gonna select the microscope for the
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lowest power possible so there we go
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low power well I hope you see the
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problem low powers not specific tell the
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viewer of your drawing what is the
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actual microscope set for and in this
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case pretend the lowest power was a
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hundred times magnification
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now that might vary depending on your
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microscope you are using don't assume
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that every microscope in the world has a
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low power of 100 so be specific and tell
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the viewer what the magnification is and
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now we can you know start to focus on
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the drawing now let's say prior to doing
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the activity that you're doing in class
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let's say you were reading through your
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book and you saw a real nice diagram of
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a plant cell maybe an animal cell
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side-by-side for comparison and then
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when you look through the microscope
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should we just start to draw from our
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memory all these beautiful cells that we
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saw in our textbook well one of the
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things I hope you'll get from this video
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is no draw an accurate representation of
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what you're actually seeing and so when
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I look at this picture right here an
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accurate representation of this picture
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I'm gonna begin with my pencil and I'm
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gonna do my drawing here and notice I
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only filled about half the view what
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about this other half well notice how
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the half that I completed looks pretty
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much like the half they did not complete
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so because the entire field of view that
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fits this pattern here I'm okay you
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don't need to fill in the entire field
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of view as long as you know what you did
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fill in is a fair representation so we
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can go ahead and just kind of leave it
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like this now let's just focus on the
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drawing you know from this picture I can
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tell that there are really three parts
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I'm gonna have to label you know one
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being the cytoplasm you know cells have
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an interior fluid filled space called
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the cytoplasm and these are eukaryotic
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plant cells taken from an onion so
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there's their nucleus and
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cuz these are plant cells I know the
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outer boundary is the cell wall so I've
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gone ahead and I've labeled neatly the
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characteristics that I'm able to
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identify you know let's take a moment to
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focus on some errors that I've seen over
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the years what if I label the cell wall
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like this with an arrow well the error
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would be to use the arrow straight lines
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touching the cell part and the reason is
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look what the arrow head it's actually
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touching the cytoplasm but it's pointing
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towards the line so there's a little bit
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of confusion what am I actually
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identifying with the arrow we can fix
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that by using a straight line that's
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actually touching the cell part you are
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identifying another common error would
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be to do this labeling the nucleus
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inside of the field of view the labels
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really should be on the outside for a
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very simple reason whatever you include
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inside of your field of view you are
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claiming you can actually see underneath
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the microscope you can't actually see
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the word nucleus typed underneath the
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microscope so a straight line touching
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the nucleus off to the side of the field
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of view and how about this label and the
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cytoplasm like this well I hope you see
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that the common mistake here would be
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the criss crossing of the lines it gets
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a little messy if you have to label four
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or five six seven different parts when
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you have you know multiple lines Criss
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crossing one another so a nice straight
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line to the center of the of the object
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you are identifying in the cytoplasm
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now I've already labeled the nucleus but
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I can still show you another common
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error I've seen over the years again one
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of the things that I want you to focus
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on is horizontal lines and horizontal
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labels if you have to label four or five
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six seven things and they're all written
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like this it gets really sloppy and
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really confusing so a nice straight line
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with a nice horizontal label and and
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there you have a good drawing
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now remember we said earlier our
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microscope was at the low power which in
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this example was a hundred times
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magnification let's zoom on into a
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higher magnification so right now I just
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have it labeled high but let's say we've
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zoomed in our microscope to the highest
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power possible on your particular
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microscope well now we have to do
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another drawing again a fair
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representation of what we're seeing we
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said earlier these are cells from an
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onion peel no reason to change the title
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now the difference being is the
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magnification in this picture let's say
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that this was a magnification of 400 X
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400 times stronger than what the human
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eye is able to see naturally well now we
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have to do our drawing and so when we do
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our drawing we're trying to do a fair
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representation of what we're seeing and
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hopefully this looks okay to you now if
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I focus on labels I can start by you
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know labeling horizontal lines touching
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the actual part the cell wall maybe next
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I can identify the cytoplasm
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maybe next I can identify a nucleus now
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notice inside of some of the nuclei
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there's a darker spot inside the nucleus
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that would be the nucleolus so with a
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higher power you can see more detail
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often which means there's more parts to
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identify and here we have another
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example of a microscope drawing so as I
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wrap up this video I want to point out
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one other common error that I've seen
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over the years here we have a hundred
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magnification onion skin cell peel on
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the left and a 400 magnification of the
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same specimen on the right when we do
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our drawing try to draw a fair accurate
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representation as we've said before same
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thing with the the picture on the right
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try to draw a fair accurate
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representation and notice this is the
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common error I've seen from time to time
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is the cells virtually look identical
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even though the picture on the right was
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magnified 400 times in the picture on
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the left only 100 so this has to be a
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mistake here because again the cells
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400 should appear much larger if I do a
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fair representation of what I'm actually
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seeing maybe it comes out looking like
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this and I can clearly see more detail
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on the picture to the right than the
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picture to the left so try to focus on
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drawing an accurate representation of
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what you're seeing so I hope you found
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this video helpful and thank you for
