Activity 1 Flashcards
from the greek words “little” and “to see”
microscope
one of the most often used and useful tools in botany
compound microscope
- degree to which an object can be enlarged
- allows you to view the parts and components of an object at a deeper level by making it bigger and easier to see
magnification
- ability of a lens to distinguish two points from each other, allowing you to unveil details in an image
- measure of clarity
- lens’s ability to clarify and sharpen the image
resolution
instrument used to magnify small objects
microscope
essential part of microscope
lenses
a simple light micrscope manipulates how light enters the eye using a ____________, where both sides are curved outwards
convex lens
consists of 2 lenses
compound microscope
compound microscope is invented in ______ by _______________
1590
Zacharias
Hans Jansen
made some of the earliest microscopes
Antoine van Leewenhoek
“animalcules”
use multiple lenses to enlarge an image
modern microscope
magnifies an object to appear ten times its actual size
eyepiece
can be adjusted to choose the magnification that best suit the viewer’s needs
magnification
- can have up to 4 objective lenses of diff magnifications
- used to view specimens on glass slides, w high magnification objectives (4x-100x range)
compound microscope
parts of the compound microscope
eyepiece (ocular lens)
monocular or binocular head
arm
nosepiece
base
objective lenses
specimen or slide
stage or platform
stage clips
aperture
abbe condenser
coarse and fine adjustment knobs
stage height adjustment
illumination
- part that is looked through at the top of the compound microscope
- typically have a magnification between 5x and 30x
eyepiece (ocular lens)
structural support that holds and connects the eyepieces to the objective lens
monocular or binocular head
supports the microscope head and attaches it to the base
arm
- holds the objective lenses and attaches them to the microscope head
- this part rotates to change which objective lens is active
nosepiece
bottom base of the microscope that houses the illumination and supports the compound microscope
base
- usually 3-5 optical lens objectives on a CM each w diff magnification levels
objective lenses
total magnification of a CM is calculated by
multiplying the objective lens magnification by the eyepiece magnificaion level
object used to hold the specimen in place along with slide covers for viewing
- most slides and slide covers are thin glass rectangles
specimen or slide
- platform upon which the specimen or slide are placed
- height of the mechanical stage is adjustable
stage or platform
clips on the stage that hold the slide in place on the mechanical stage
stage clips
- disc or iris diaphragm
- circular opening in the stage where the illumination from the base of the CM reaches the platform of the stage
aperture
- lens condenses the light from the base illumination and focuses it onto the stage
- this piece of the CM sits below the stage and typically acts as a structural support that connects the stage to arm or frame of the microscope
abbe condenser
- adjusts the focus of the M
- increase or decrease the level of detail seen when looking at the slide or specimen through the eyepiece of the compound microscope
coarse and fine adjustment knobs
- adjusts the position of the mechanical stage vertically or horizontally
stage height adjustment
light used to illuminate the slide or specimen from the base of the microscope
illumination
most commonly used source of illumination for CM
low voltage halogen bulbs
OBJECTIVE LENSES
state the 4 diff OL, their color and their magnification
SPECIFIC OBJECTIVE
red
4x
LOW POWER OBJECTIVE
yellow
10x
HIGH POWER OBJECTIVE
blue
40x
OIL IMMERSION OBJECTIVE
white
100x
TYPES OF MICROSCOPES
light microscope
scanning electron microscope
transmission electron microscope
phase-contrast microscope
interference microscope
confocal LASER scanning microscope
stereomicroscope
- oldest and most straightforward type of microscope that uses a series of glass lenses, which first focus a bean of light onto or through an object, and convex objective lenses to enlarge the image formed
light microscope
- works by impacting a bean of high-energy electrons on the surface of the specimen and obtaining signals from the specimen surface to determine its properties
- gives 3d view w high magnification and high resolution
- mainly used to study the surfaces of cells and viruses
scanning electron microscope
- a focused electron beam is passed through an ultrathin specimen (less than 100nm thick), resulting in an interaction betwenn the specimen’s atoms and the electronic beam, and generating a projection image
- used to examine microanatomy of biological tissues, cells, and organisms
transmission electron microscope
- light microscopy technique used to enhance the contrast of images of transparent, colorless, unstained, living biological specimens (phase objects)
- light is diffracted (scattered) and retarded based on the refractive index of the object
- negative phase contrast:
- positive phase contrast:
phase-contrast microscope
background is dark, specimen is bright
specimen is dark, background is bright
- uses a prism to split light into 2 slightly diverging beams
- one beam pass through the specimen (and is retarded) and the other bypasses the specimen
- both beams are recombined with the help of a mirror
- provides 3d appearance of thicker specimens at higher magnification
interference microscope
- works by passing a laser beam through a light source aperture which is then focused by an objective lens into a small area on the surface of the sample
- an image is built up pixel-by-pixel by collecting the emitted photons from the fluorophores in the sample which allows for 3d reconstruction of a sample from high-resolution stacks of images
- used to observe organelles in cell biology and etc
confocal LASER scanning microscope
- aka dissecting microscope
- low power microscope which combines 2 optical paths for each eye to provide a 3d view of the specimen
- used to visualize surfaces of plant specimens, fabrics, jewelry, circuit components
stereomicroscope
