BIO 210- LAB MIDTERM EXAM
QUESTIONS AND ANSWERS 100%
ANSWERED.
Ex. 1 Parfocal - ANSWERability of a microscope to remain in focus when changing from
one objective lens to another with little or no adjustment; when focusing on a specimen,
start with the lowest power objective first and increase magnification by rotating more
powerful lenses into position
Ex. 1 Components of the scope - ANSWER1. arm- connects base to body tube that
contains lenses
2. base- light source, on/off switch/voltage regulator)
3. oculars len- eye pieces (10x magnification)
4. revolving nose piece with different objective lenses (10x, 40x, 100x [immersion oil])
5. course adjustment knob- large knob on either side of arm that moves stage up or
down rapidly to focus specimen
6. fine adjustment knob- small knob in center of course adjustment knob that moves
stage up or down slightly to adjust sharpness of specimen focus
7. stage- platform that hold specimen (mechanical stage knobs- moves specimen
around on stage)
8. condenser- directs and condenses rays from light source at base; can be moved up
or down by knob on right side of arm below focus knobs
9. diaphragm- opens and shuts condenser aperture to allow more or less light through
condenser to specimen
10. blue filter- blue glass in condenser
Ex. 1 How to calculate total magnification - ANSWERproduct of the magnifying power of
the ocular lens times the magnifying power of objective lens
*ocular lens (10x) X objective lens (40x) = total magnification (400x)*
Ex. 1 Resolution and 4 ways to minimize resolution - ANSWERability of a microscope to
separate or distinguish between small objects that are close together
1. raise condenser
2. open diaphragm
3. use blue filter
4. use immersion oil with 100x objective
Ex. 1 Proper viewing procedure - ANSWER- start at lowest objective
- look for wax pencil mark
1. hold slide up and see where smear is
2. put it on slide and center it
3. scope off, dial towards you
, 4. scope on, dial all the way up
5. put on yellow
6. bring stage all the way up
7. course knob towards you
8. fine knob 1-1 1/2 turns, if bad go the other way
Ex. 1 How to use immersion oil - ANSWER******use on 100x*******
Ex. 7 Ubiquity - ANSWERthe state or capacity of being everywhere
Ex. 7 How bacterial growth appears on/in different types media - ANSWERbacterial
growth is indicated by:
1. turbidity of liquid
2. colony solid
Ex. 8 General characteristics of fungi - ANSWER- allergies, lab contamination,
decomposition
- heterotrophic
1. eukaryotic: fungi, worms, plants, animals
2. non photosynthetic
3. no tissues
4. chitin: cell walls
5. propagate using spores
6. non motile
Ex. 8 Basic difference between molds and yeasts - ANSWERMolds
- filamentous growth that gives them a "fuzzy" appearance
- hyphae: filaments with terminal spores
1. septate hyphae: have cross-walls
2. non-septate hyphae: no cross-walls
- mycelium: mass of hyphae that intertwines into a mat of growth
- types of asexual spores
1. sporangiospores: spores encased in a membranous sac called a sporangium
2. conidia: spores are not encased in a sac - formed on a specialized hypha called a
condiospore
- types of molds (3)
1. rhizopus: has long non-septate hyphae with sporangiospores and root-like hyphae
called rhizoids; rarely the hyphae are septate. Mycelial growth is gray with black
sporangiospores edges
2. aspergillus: has septate hyphae with conidia. Mycelial growth is black from dense
conidia concentration
3. penicillium: has septate hyphae with conidia. Mycelial growth is bluish-green
Yeasts
- form moist, smooth round colonies of growth on agar surface
- cells are oval in shape, and may form budding cells that break away from parent cel
QUESTIONS AND ANSWERS 100%
ANSWERED.
Ex. 1 Parfocal - ANSWERability of a microscope to remain in focus when changing from
one objective lens to another with little or no adjustment; when focusing on a specimen,
start with the lowest power objective first and increase magnification by rotating more
powerful lenses into position
Ex. 1 Components of the scope - ANSWER1. arm- connects base to body tube that
contains lenses
2. base- light source, on/off switch/voltage regulator)
3. oculars len- eye pieces (10x magnification)
4. revolving nose piece with different objective lenses (10x, 40x, 100x [immersion oil])
5. course adjustment knob- large knob on either side of arm that moves stage up or
down rapidly to focus specimen
6. fine adjustment knob- small knob in center of course adjustment knob that moves
stage up or down slightly to adjust sharpness of specimen focus
7. stage- platform that hold specimen (mechanical stage knobs- moves specimen
around on stage)
8. condenser- directs and condenses rays from light source at base; can be moved up
or down by knob on right side of arm below focus knobs
9. diaphragm- opens and shuts condenser aperture to allow more or less light through
condenser to specimen
10. blue filter- blue glass in condenser
Ex. 1 How to calculate total magnification - ANSWERproduct of the magnifying power of
the ocular lens times the magnifying power of objective lens
*ocular lens (10x) X objective lens (40x) = total magnification (400x)*
Ex. 1 Resolution and 4 ways to minimize resolution - ANSWERability of a microscope to
separate or distinguish between small objects that are close together
1. raise condenser
2. open diaphragm
3. use blue filter
4. use immersion oil with 100x objective
Ex. 1 Proper viewing procedure - ANSWER- start at lowest objective
- look for wax pencil mark
1. hold slide up and see where smear is
2. put it on slide and center it
3. scope off, dial towards you
, 4. scope on, dial all the way up
5. put on yellow
6. bring stage all the way up
7. course knob towards you
8. fine knob 1-1 1/2 turns, if bad go the other way
Ex. 1 How to use immersion oil - ANSWER******use on 100x*******
Ex. 7 Ubiquity - ANSWERthe state or capacity of being everywhere
Ex. 7 How bacterial growth appears on/in different types media - ANSWERbacterial
growth is indicated by:
1. turbidity of liquid
2. colony solid
Ex. 8 General characteristics of fungi - ANSWER- allergies, lab contamination,
decomposition
- heterotrophic
1. eukaryotic: fungi, worms, plants, animals
2. non photosynthetic
3. no tissues
4. chitin: cell walls
5. propagate using spores
6. non motile
Ex. 8 Basic difference between molds and yeasts - ANSWERMolds
- filamentous growth that gives them a "fuzzy" appearance
- hyphae: filaments with terminal spores
1. septate hyphae: have cross-walls
2. non-septate hyphae: no cross-walls
- mycelium: mass of hyphae that intertwines into a mat of growth
- types of asexual spores
1. sporangiospores: spores encased in a membranous sac called a sporangium
2. conidia: spores are not encased in a sac - formed on a specialized hypha called a
condiospore
- types of molds (3)
1. rhizopus: has long non-septate hyphae with sporangiospores and root-like hyphae
called rhizoids; rarely the hyphae are septate. Mycelial growth is gray with black
sporangiospores edges
2. aspergillus: has septate hyphae with conidia. Mycelial growth is black from dense
conidia concentration
3. penicillium: has septate hyphae with conidia. Mycelial growth is bluish-green
Yeasts
- form moist, smooth round colonies of growth on agar surface
- cells are oval in shape, and may form budding cells that break away from parent cel
