ZOO LAB MT
The Microscope
- instruments used to enlarge or enhance images
of minute objects so as they can be studies and
for observation purposes
- “Micro” ~ tiny; “scope” ~ view or look at
- Compound light microscope ~ contains two
lenses capable of magnifying, and a variety of
adjustment knobs to resolve or to focus the
image/specimen
a. Eyepiece - contains ocular lens
b. Nosepiece - holds LPO/HPO, can be rotated to
change magnification
c. Objective lenses (LPO/HPO) - ranges from 10x
to 40x
d. Stage clips - hold slide in place
e. Stage - support slide
f. Diaphragm - regulates amount of light
g. Coarse adjustment knob - allows stage to move
up and down for focusing
h. Fine adjustment knob - to sharpen image
Why must one center and focus the object in the field of
view under low power before switching high power?
- The depth of focus is great on the lowest power
objective
Magnification
- Size of photo
Resolution
- Clearness/ sharpness of photo
What is the total magnification produced when HPO is
used? Show calculation.
(4x)(10x) = 40x
(10x)(10x) = 100x
(40x)(10x) = 400x
Types of microscopes
TEM - can see insides of cell
SEM - see cell itself
Fluorescent microscope - uses dyes to see cell
The Cell
What is cell theory?
- all living organisms are composed of cells
(schleiden & Schwann)
- Cell is basic unit of life (schleiden & Schwann)
- All cells are produced by the division of
pre-existing cells (virchow)
1. SER - synthesis of lipids
2. Ribosomes - consists of rna and associated
proteins
3. Mitochondria - produces energy (ATP)
4. Centriole - two in animals, none in plants
5. Nucleus - control center; dna
6. RER - synthesis of proteins
7. Golgi apparatus - packaging of synthesized
proteins
8. Cell membrane - semipermeable membrane
layer which serves as protection of cells
9. Lysosomes - contains digestive enzymes for
waste disposal; suicidal bags
Endosymbiotic theory
- mitochondria and chloroplasts are free living
Stains
- methylene blue (cheek cell)
- Iodine solution (plants)
Importance of transport in the cell
- can happen inside the cell or from one cell to
another
- Transport materials for metabolic activities
Diffusion
- high to low concentration
- Molecule is Soluble
- No charge
