LP1 Microbiology Flashcards
Bright Field Illumination
Illumination produced by the passage of visible light through the condenser of a light microscope. Light is concentrated on the specimen and transmitted through the specimen, Objects are seen against a light background.
Total Magnification
Ocular Lens (i.e. 10X) x Objective Lens (i.e. 40X) = Total Magnification (10X x 40X= 400X)
Parafocal
The ability to change from one objective to another with only minimal adjustments for focusing. Increases the efficiency of the microscope. (“Par” means equal)
Transmission
Passage of light through an object.
Adsorption
Light rays do not pass or bounce off of an object but are taken up by the object.
Reflection
Light strikes an object and bounces back.
Resolution
The ability to see objects as separate and discrete entities. Oil is added to 100X objective lenses to improve clarity.
Refraction
The bending of light as it passes through different media. (i.e. Lens-glass slide-specimen-air) Causes a blurred image as light bends clarity is lost.
Fine Adjustment
Changes the distance between the objective lens and the specimen with small motor movements, aids in focusing the specimen.
Arm
Part of the microscope that you grab to move while supporting the bottom of the microscope.
Course Adjustment
Changes the distance between the objective lens and the sample with large motor movements, aids in focusing the specimen.
On/Off switch
Turns the light source on or off.
Nose piece
What holds the objective lenses
Eyepiece
Ocular lens
Objective lens
Magnifies the image before it passes through the body- tube to the ocular lens in the eyepiece.
Diopter Adjustment
Adjustment on the eyepiece/ocular lens
Joseph Lister
“Father of Antiseptic Surgery”. Initiated the use of Carbolid Acid (Phenol) to reduce infections during surgical procedures. Phenol is harmful to living cells.
Obligate Aerobe
A bacterium that must have free oxygen to grow.
DNA base pairs
Complementary base pairing ensures the accurate coding and decoding of cell information. Deoxynucleic Acid (DNA) pairs are Adenine (A)-Thymine (T), and Guanine (G) -Cytosine (C). Carries genetic information.
Plasmid
Also called extrachromosomal DNA; a small circular independently replicating piece of DNA in a cell that is not part of its chromosome and can be transferred to another cell.
Cytoplasm
Semi-fluid substances that supports organelles, site of chemical reactions in the cell.
Conjugation
The transfer of genetic information from one bacterial cell to another by means of conjugation pili.
Cell membrane/plasma membrane
Semi-permeable membrane regulating what goes in and out of the cell.
cell wall
Maintains the shape of the cell, prevents cell from busting when fluids flow into the cell via osmosis, based on molecular structure retains the stains during staining procedures.
transduction
The transfer of genetic material from one bacterium to another by a macrophage.
transformation
A change in an organism’s characteristics through the transfer of naked DNA.
transfer RNA
Carries the anti-codon for specific amino acids
Messenger RNA
Carries the message in the form of a codon for specific amino acids
Ribosomal RNA
Site of protein synthesis
Eukaryotic cell
A cell that has a distinct cell nucleus and other membrane-bound structures.
base
The part of a microscope that sits on a table or bench.
light source
The part of the microscope that illuminates samples.
iris diaphram
The part of the microscope that controls the amount of light on a sample.
condensor
The part of the microscope that collects and concentrates the light that illuminates the sample.
stage
The part of the microscope that the slide sits on.
slide holder
The part of the microscope that holds the slide. Clips.
Thayer-Martin Agar
A solid media that selects for pathogenic strains of the genus Neisseria.
Selective media
Selective media selects for certain bacteria while inhibiting the growth of other microorganisms.
Differential media
Differentiates between different organisms based on a macroscopic characteristics (i.e. sugar fermenting, pH color change, etc.)
MacConkey Agar
A solid media that selects for gram negative organisms and differentiates from lactose fermenting organisms.