Lesson 1 and 2- stats and Microscope Flashcards
Compound microscope:
- has larger magnification (40x-1000x )
to see bacteria, tissue ets
Requires a slide
Revolving nose piece that has different objective lenses
Light source comes from the bottom and transmits light through the organism
Top lens is called ocular lens
Produces a 2D image
Dissecting microscopes
usually for something you can see
Can use slides
Has a separate light source (you need to bring a lamp)
Lens points down at the image (A)
Low magnification: 7x-30x
Produces a 3D image (since what you are handling are usually organisms or something)
Uses reflected light for opaque images
Stereoscopic
produces a 3D image
Light microscope
Magnifies image to make it look larger than it actually is
Focuses image
is paragocal and and parcentered
*both compound and dissecting are light microscopes
result of magnification and focussing is an increase in resolution
resolution
the ability to tell that two objects that are very close together are distinct objects rather than just one
all light/ compound microscopes have a
Illumination system
Illumination system
Light source
Condenser
Iris diaphragm
Condenser (Illumination system
focuses light from the light source onto the specimen (thing at the bottom of the slide)
Iris diaphragm (Illumination system
controls the amount of light. When its open, it is brighter and you loose contrast. Staining slides increase contract. When its closed, it gives more contrast.
Imaging system
Oculars
objectives
stage
Oculars (Imaging system)
can be monocular or binocular. (always provides 10x magnification), you can have either one ocular lens or two
objectives (Imaging system)
has many different magnifications
stage (Imaging system)
holds the microscope slide (you can clip it onto the stage)
should always be in the lowest setting
what is the smallest magnification you can see
The smallest magnification we can see is 40x (since ocular is 10 and lens is 4)
Total magnification
ocular magnification x objective magnification
Field of view
area that you are viewing in microscope. When objective increases, the field of view decreases. This varies from microscope to microscope
Stage micrometer
its a slide that is used as.as a ruler
Each of these hatch marks is etched at 0.01mm and 0.1 mm intervals (0.01 is the small ticks at the beginning)
Area of the FOV
Use diameter to calculate area. A + pi r^2 = pi (d/2)^2
how to calibrate the ocular micrometer
Stage micrometer can be used to calibrate the ocular micrometer
ocular micrometer
helps you to look at an image under the microscope and count how many ticks it is if its microscopic. There are no units because it depends on the magnification
callibrate ocular
line up with stage micrometer (known distance)
Count the stage lines and multiply it by 0.1 mm/ stage line
Divide this by the ocular units to get the answer
You might have to twist the ocular lens to calibrate it
microorganisms
organisms that are not visible to the naked eye
Research
answering a question using the scientific process.
Wet mounts
slides prepared in a wet medium (can be alive)
diagnosing
identify the nature of (an illness or other problem) by examination of the symptoms.
parafocAL
is one which, if it is in focus with one objective, when the objective is rotated, will remain (mostly) in focus.
paracentered
object in the center of view will remain in the center when the objective is rotated.
calculate mean
add up all numbers and calculate averag
median
middle number
range
lowest to higher number and subtract
standard deviation
do summation plus then take the button x with line on top, 2nd then square root x
variance
s squared
null hypothesis
states that nothing occured
how to calculate the confidence interval
mu = x(with a line) +/- t(s/rootn)
x(line) is sample mean
n is sample size used to calculate
s is standard deviation
t value of student t
what happens to confidence interval when sample size gets smaller
it gets larger since you are more unsure of the data
bar graph
include the confidence intervals, axis labels with graph and everything
write out the confidence interval eqn
mu = x(with a line) +/- t(s/rootn)
write out a sample bar graph
ah
write out a sample line graph
ah
histogram
1) divide data into groups of equal size and covers all categories
2) create axis with categories
3) put data point in the frequency that the data goes into that category ex 6 times people chose cats
4) connect the line
difference between histogram and bar graph
histogram shows what numbers occur the most and how they occur
metric conversions??
go look up is prefix unit conversions real quick
mean does not provide information about
RANGE, OUTLIERS, HOW DISTORTED DATA IS
review the whole lab and the graphing
ok
orientation in compound microscope
letters are flipped upside down
the image moves in the opposite direction as you move the slide to the right t and left
brightness
brightness decreases as you increase magnification
to find how much more area you can see in FOV
divide larger field by smaller field
always start with
slide in lowest position and lowest objective on
depth of field
you can’t see all things in focus at high magnification (ex threads)
high power requires the most __
light
dissecting microscope orientation
letter is facing the same way, image moves in the same direction that you move the slide
dissecting vs compound microscopes
dissecting uses reflected illumination while compound use transmitted illumination
go do some practice calculations from the powerpoint
PLEASE
go to page 23 on lab manual and name the lab microscope parts
PLEAS
Population
any set of individuals, objects or data
Sample
a random observed subgroup of the population
null hypothesis
state that nothing happened and then:
The observed difference in the means is due solely to change sampling variation.
