BIMM 120 – Midterm questions well answered graded A+

BIMM 120 – Midterm questions well answered
graded A+
1. 4 parts needed
-Cytoplasm
for Bacterial
-Connected singular chromosome
cells
-Plasma/cell membrane
-Cell wall

Phospholipid bilayer! ’Allowing for selective permeability
2. Cell
remember: hydrophilic head and hydrophobic tails
membrane
has...

3. Compare saturat- - saturated are straight tails
ed or -unsaturated are bent tails
unsaturat- ed
fatty acids




4. Main compo- -LPS: far outside; toxic (immune system can detect easily)
nents of the -Lipid A: anchors LPS to OM
out- er -Lipoproteins: anchors OM to cell wall
membrane: -Porins: for transport

5. The cell wall... Made up of peptidoglycan (differs from fungal and plant cell walls)

6. The staining
peptidogly-
can for gram
+/- is...


7. Describe
gram
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, BIMM 120 – Midterm questions well answered
graded A+
thick for gram positive and
thin for gram negative

1. Application of crystal
violet to gram +/-. Dyes
it purple.
2. Application of
iodine (mordant) forms
the iodine-crystal violet
complex in both but
makes the dye stick to
the gram + as it is
thicker peptidoglycan.
3. Alcohol wash will
decolorize the gram -
cells but not the gram
+.
4. Application of
safranin will act as a
counterstain, staining the
gram - which will turn
pink.
OVERALL: gram + is
purple and gram - is pink.




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