Lab 4 & 5 Flashcards
after using a microscope always?
leave lowest power objective 4x in place
remove the slide
clean the stage
Parfocal
objective lenses
- means once focused on an object at lower power , will only have to make minor fine focus adjustments when you increase the magnification by switching to a higher power objective lens
total magnification
determined by all the lenses through which it is viewed
objective lens x ocular lens (10x) = total magnification
4 x 10 = 40
10 x 10 = 100
40 x 10 = 400
inversion
what you the object as, as you look through the microscope
- refers to the image being upside down and reversed
moving the slide up and left what happens to image?
goes opposite way
moves down and right
the objective lenses are concentrically mounted so the image seen at the higher magnification is?
the middle of the image seen at the lower power
depth of focus
the vertical distance that remains in focus at one time
depth of focus
as the stage moves upwards (or the objective moves downward) which object come into focus first? top middle or bottom?
top
Diameter of field
- the circle visible through the lens
- length across the lighted portion of the image from one edge to the other edge
the determination of the size of the Diameter of Field at each ojective power will help?
determine the approximate sizes of the specimens observed
1 mm = ? micrometer
1000 micrometer (um)
Objective Lens Magnification
4x
scanning lense
- red
Objective lens magnification
10x
low power lens
- yellow
Objective lens magnification
40x
High power lens
- blue
scanning magnification vs scanning diameter
4x = 40 = 5000 um
low power magnification (lpm) vs low power diameter (LPD)
10x = 100 = 2000 um
High Power Magnificationn (LPM) vs High Power Diameter (HPD)
40x = 400 = 500 um HPD = LPD x (LPM/HPM)
does low power or high power have a larger field of view that allows you to see more of the object?
low power
Which has a smaller field but magnifies to a greater extent?
high power
wet mount
specimen suspended in liquid
when drawing always label?
nucleus, cell membrane, and cytoplasm
What do you use to clean lenses?
special lens paper
plasma membrane
membrane at the boundary of every cell that acts as a selective barrier to the passage of ions and molecules into and out of the cell
- consists of phospholipid bilayer with embedded protein
cell wall
a protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists
- protects the cell and helps maintain its shape
