Term
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Definition
| differences in intensity between two objects or between an object and its background |
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| The most common microscope |
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Definition
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Term
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Definition
the specimen is made to appear light against a dark background.
prevent light from directly entering the objective lens.
light rays are reflected inside the condenser, so that they pass into the slide at such an oblique angle that they completely miss the objective lens.
increases contrast and enables observation of more details than are visible in bright-field microscopy. |
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Definition
| use the alignment or misalignment of light waves to achieve the desired contrast between a living specimen and its background |
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Definition
| use invisible ultraviolet light to cause specimens to radiate visible light |
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Definition
| use lasers to illuminate fluorescent chemicals in a thin plane of a specimen |
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Term
| Two Types of Bright Field Microscopes |
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Definition
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Term
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Definition
| contains a single magnifying lens, is more similar to a magnifying glass than to a modern microscope |
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Term
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Definition
| did not invent the microscope, he was the finest lens maker of his day. Capable of 300x magnification. |
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Term
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Definition
| uses a series of lenses for magnification |
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Term
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Definition
the lens immediately above the object being magnified.
a series of lenses that not only create a magnified image but also are engineered to reduce aberrations in the shape and color of the image. |
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Term
| Types of Objective Lenses |
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Definition
scanning objective lens (4×)
low-power objective lens (10×)
high-power lens or high dry objective lens (40×)
oil immersion objective lens (100×) |
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Term
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Definition
| have three or four objective lenses mounted on it |
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Definition
| increases magnification and resolution |
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Term
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Definition
historically, cedarwood oil; today, more commonly a synthetic oil.
Because light is traveling at a uniform speed through the slide, the immersion oil, and the glass lens, it does not refract. |
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Term
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Definition
| the distance between the lens and the specimen |
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Definition
the lenses closest to the eyes.
Magnifies an addition (10x) |
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Term
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Definition
| Microscopes with a single ocular lens |
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Term
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Definition
| Microscope with two ocular lenses |
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Term
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Definition
| determined by multiplying the magnification of the objective lens by the magnification of the ocular lens |
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Term
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Definition
| directs light through the specimen AND one or more mirrors or prisms that deflect the path of the light rays from an objective lens to the ocular lens |
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Definition
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Definition
| A photograph of such a microscopic image |
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Definition
Used to examine living microorganisms or specimens that would be damaged or altered by attaching them to slides or staining them.
treats one set of light rays differently from another set of light rays |
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Term
| Types of Phase Microscopes |
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Definition
| phase-contrast and differential interference contrast microscopes |
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Term
| phase-contrast microscopes |
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Definition
produce sharply defined images in which fine structures can be seen in living cells.
e.g. cilia and flagella |
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Term
| Differential interference contrast microscopes |
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Definition
AKA: Nomarski microscopes.
significantly increase contrast and give an image a dramatic three-dimensional and shadowed appearance.
can also produce unnatural colors, which enhance contrast. |
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Term
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Definition
composed of a single basic dye, such as crystal violet, safranin, or methylene blue.
used to determine size, shape, and arrangement of cells. |
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Term
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Definition
| involve no more than soaking the smear in the dye for 30–60 seconds and then rinsing off the slide with water |
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Term
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Definition
Most stains used in microbiology are these.
use more than one dye so that different cells, chemicals, or structures can be distinguished when microscopically examined. |
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Term
| Common Differential Stains |
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Definition
Gram Stain.
Acid fast stain.
Endospore stain.
Gomori methenamine silver stain.
hematoxylin and eosin stain |
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Term
| Gram Stain invented by ____ in ____. |
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Definition
| Hans Christian Gram ; 1884 |
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Term
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Definition
| differentiates between two large groups of microorganisms: purple-staining Gram-positive cells and pink-staining Gram-negative cells |
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Term
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Definition
Smear is made and heat fixed.
1. Crystal Violet, 1 minute. (Primary stain).
2. Gram's Iodine for 1 minute, then rinse with water.
3. Rinse with ethanol and acetone, 10-30 seconds, then rinse with water.
4. Safranin, 1 minute. then rinse with water.
Blot dry the slide. |
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Term
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Definition
| a substance that binds to a dye and makes it less soluble |
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Term
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Definition
Ethanol and acetone.
breaks down the thin cell wall of Gram-negative cells, allowing the stain and mordant to be washed away |
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Term
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Definition
safranin.
provides a contrasting color to the primary stain. |
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Term
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Definition
| 95% ethanol (instead of acetone/ethanol mixture). |
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Term
| Reasons to classify organisms |
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Definition
1. to bring a sense of order and organization to the variety and diversity of living things.
2. to enhance communication, to make predictions about the structure and function of similar organisms
3. to uncover and understand potential evolutionary connections. |
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Term
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Definition
| sorts organisms on the basis of mutual similarities into nonoverlapping groups |
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Definition
the science of classifying and naming organisms.
Consists of classification, nomenclature, identification. |
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Definition
| the assigning of organisms to taxa based on similarities |
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Definition
| the rules of naming organisms |
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Definition
| the practical science of determining that an isolated individual or population belongs to a particular taxon |
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Definition
| Created Our current system of taxonomy |
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Definition
similar organisms that can successfully interbreed.
a group of organisms that interbreed to produce viable offspring. |
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Definition
| populations of cells that arose from a single cell |
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Definition
AKA: phage.
a virus that inserts its DNA into a bacterium. |
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Definition
| Many phages are so specialized for their particular bacterial strain that scientists have used phages to identify and classify bacteria |
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Definition
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Definition
| genera sharing common features |
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Definition
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Definition
| orders are groups into these |
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Definition
| classes are grouped into these |
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Definition
| phyla are grouped into these |
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Term
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Definition
Domain.
Kingdom.
Phylum.
Class.
Order.
Family.
Genera.
Species. |
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Definition
used in naming.
always contains only lowercase letters and is usually an adjective. |
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Definition
| use of 2 words in the name |
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Definition
sequenced the nucleotides of the smaller subunits of ribosomal RNA (rRNA) in an effort to unravel the relationships among these organisms.
Defined Domains: eukarya, bacteria, archea |
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