MCB 2010 QUESTIONS AND ANSWERS SURE A+
✔✔Fimbriae - ✔✔Used by bacteria to adhere to one another and to substances in
environment
✔✔Pili - ✔✔Bacteria typically have only one or two per cell.
Transfer DNA from one cell to another (conjugation)
✔✔Cytoplasmic Membrane - ✔✔phospholipid bilayer
Composed of lipids and associated proteins
Energy storage
✔✔endospore formation - ✔✔
✔✔Glycocalyes are different in prokaryotes and eukaryotes - ✔✔true
✔✔metric measurements - ✔✔meter- decimeter- centimeter- millimeter- micrometer-
nanometer
✔✔simple bright field microscopes - ✔✔contains one magnifying lense
✔✔compound bright field microscopes - ✔✔Series of lenses for magnification
Light passes through specimen into objective lens
Oil immersion lens increases resolution
Have one or two ocular lenses
Total magnification = magnification of objective lens × magnification of ocular lens
Most have condenser lens (direct light through specimen)
✔✔Dark-Field Microscopes - ✔✔Best for observing pale objects and external features
Only light rays scattered by specimen enter objective lens
Specimen appears light against dark background
Increases contrast and enables observation of more details
Useful for examining small or colorless cells
, ✔✔Phase Microscopes - ✔✔Used to examine living organisms or specimens that would
be damaged/altered by attaching them to slides or staining
✔✔Fluorescence Microscopes - ✔✔Direct UV light source at specimen
Specimen radiates energy back as a longer, visible wavelength
UV light increases resolution and contrast
Some cells are naturally fluorescent; others must be stained with fluorescent dyes
Used in immunofluorescence to identify pathogens and to make visible a variety of
proteins
✔✔Electron Microscopy - ✔✔greater resolving power and magnification
Magnify objects 10,000× to 100,000×
Detailed views of bacteria, viruses, internal cellular structures, molecules, and large
atoms
Two types:
Transmission electron microscopes
Scanning electron microscopes
✔✔Chromophore - ✔✔colored portion of the dye used for staining
✔✔Acidic dyes - ✔✔Stain alkaline structures
✔✔Basic dyes - ✔✔Stain acidic structures
✔✔Taxonomy - ✔✔consists of classification, nomenclature, and identification
Organize large amounts of information about organisms
Make predictions based on knowledge of similar organisms
Help understand evolutionary connections
✔✔Physical Characteristics - ✔✔distinct appearance
✔✔Biochemical Tests - ✔✔Laboratory scientists use these to identify pathogens
✔✔Serological Tests - ✔✔The study of antigen-antibody reactions in laboratory settings
✔✔Analysis of Nucleic Acids - ✔✔Nucleic acid sequence can be used to classify and
identify microbes
✔✔ Who made the first microscope? - ✔✔Antoni van Leeuwenhoek
✔✔Who were the two scientists that disproved spontaneous generation? - ✔✔Redi and
Pasteur
✔✔Fimbriae - ✔✔Used by bacteria to adhere to one another and to substances in
environment
✔✔Pili - ✔✔Bacteria typically have only one or two per cell.
Transfer DNA from one cell to another (conjugation)
✔✔Cytoplasmic Membrane - ✔✔phospholipid bilayer
Composed of lipids and associated proteins
Energy storage
✔✔endospore formation - ✔✔
✔✔Glycocalyes are different in prokaryotes and eukaryotes - ✔✔true
✔✔metric measurements - ✔✔meter- decimeter- centimeter- millimeter- micrometer-
nanometer
✔✔simple bright field microscopes - ✔✔contains one magnifying lense
✔✔compound bright field microscopes - ✔✔Series of lenses for magnification
Light passes through specimen into objective lens
Oil immersion lens increases resolution
Have one or two ocular lenses
Total magnification = magnification of objective lens × magnification of ocular lens
Most have condenser lens (direct light through specimen)
✔✔Dark-Field Microscopes - ✔✔Best for observing pale objects and external features
Only light rays scattered by specimen enter objective lens
Specimen appears light against dark background
Increases contrast and enables observation of more details
Useful for examining small or colorless cells
, ✔✔Phase Microscopes - ✔✔Used to examine living organisms or specimens that would
be damaged/altered by attaching them to slides or staining
✔✔Fluorescence Microscopes - ✔✔Direct UV light source at specimen
Specimen radiates energy back as a longer, visible wavelength
UV light increases resolution and contrast
Some cells are naturally fluorescent; others must be stained with fluorescent dyes
Used in immunofluorescence to identify pathogens and to make visible a variety of
proteins
✔✔Electron Microscopy - ✔✔greater resolving power and magnification
Magnify objects 10,000× to 100,000×
Detailed views of bacteria, viruses, internal cellular structures, molecules, and large
atoms
Two types:
Transmission electron microscopes
Scanning electron microscopes
✔✔Chromophore - ✔✔colored portion of the dye used for staining
✔✔Acidic dyes - ✔✔Stain alkaline structures
✔✔Basic dyes - ✔✔Stain acidic structures
✔✔Taxonomy - ✔✔consists of classification, nomenclature, and identification
Organize large amounts of information about organisms
Make predictions based on knowledge of similar organisms
Help understand evolutionary connections
✔✔Physical Characteristics - ✔✔distinct appearance
✔✔Biochemical Tests - ✔✔Laboratory scientists use these to identify pathogens
✔✔Serological Tests - ✔✔The study of antigen-antibody reactions in laboratory settings
✔✔Analysis of Nucleic Acids - ✔✔Nucleic acid sequence can be used to classify and
identify microbes
✔✔ Who made the first microscope? - ✔✔Antoni van Leeuwenhoek
✔✔Who were the two scientists that disproved spontaneous generation? - ✔✔Redi and
Pasteur
