AIM: What do the organelles of plant cells look like
under a microscope?
DN: How do we find the magnification of a
microscope? Find the magnification of low power
(yellow) and high power (blue) under the microscope
in front of you.
HW: Castle Learning- cells
Cells Exam- Tuesday
–Cellular organization, cell theory, life
functions, cell organelles, microscope
Total Magnification
Ocular Lens X Objective lens= total magnification
Low Power (yellow): 10 X 10 = 100X
High Power (blue): 10 X 40 = 400X
Pre-Lab Questions
1. What is an organelle?
Structure inside a cell that carries out a specific
function.
2. What is the difference between a plant cell and
an animal cell?
Plant cell: chloroplast and cell wall
Animal Cell: centrioles
3. What is the function of the following
organelles?
• Cell Wall: Protection and Support
• Cell membrane: determines what can enter
and leave the cell
• Vacuole: storage of water/nutrients/waste
• Chloroplast: photosynthesis
• Cytoplasm: where all cellular activity takes
place
• Nucleus: controls all cellular activity
Elodea
Elodea: Invasive Species in NYS
Naja
How to make a wet mount slide
1. Prepare a wet mount slide
2. Focus under scanning on microscope (red)
3. Switch to low power (yellow)
1. Can turn coarse and fine adjustment to focus
2. Draw one row of cells across the middle- be sure to
count how many cells fit across!!
4. Switch to high power- don’t move coarse
adjustment before switching!!
1. Can only turn fine adjustment
2. Draw one row of cells across the middle
3. Label the chloroplasts and cell wall
Elodea:
yellow- low power 100X
Elodea:
blue- high power 400X
Cell Measurement
• 1mm = 1000um
• FOV= 2mm
2mm = _______________ um
• Divide FOV (um) by # of cells that fit across
To convert:
• mm  um: multiply by 1000 (move decimal 3
places to right)
• Um  mm: divide by 1000 (move decimal 3 places
to the left)