Class: Biology 2320
Name: Phuong Nguyen
1) What are the differences and similarities between prokaryotic and eukaryotic cells?
Similarities:



Differences:
Prokaryotic
Cell membrane
Genetic material
Ribosomes
Eukaryotic
-Internal membrane, absent
- Internal membrane, present
+ no nucleus
+ nucleus
+ no membrane- bound
+ membrane- bound organells
organells
- does not contain cellulose
-contain cellulose
- cilia absent
-cilia maybe present
2) What are function of cellular structures?
o Capsule- :
attach a bacterial cell to specific surfaces or to other cells
o Fimbriae-:
- To move across a surface via a process similar to pulling an object with a
rope (in bacteria)
- Slimy masses of microbes adhering to a substrate and conducting
electrical signals among cells (in biofilm)
o Cell wall-:
To give the cell strength and structure, and to filter molecules that pass in
and out of the cell.
o Cytoplasmic membrane-:
- Controlling the passage of substances into and out of the cell.
- Producing molecules for energy storage and for harvesting light energy in
photosynthetic bacteria.
o Flagella-:
 Rotation propels bacterium through environment (360o)
 Rotation reversible; can be counterclockwise or clockwise
 Bacteria move in response to stimuli (taxis)
-Runs: rotate counterclockwise
-Tumbles: rotate clockwise
 Do not rotate but undulate rhythmically
o Pili-:
Mediate the transfer of DNA from one cell to another via process termed
conjugation
o Ribosome-:
Making protein
o Endospore-:
Ensure the survival of a bacterium through periods of environmental stress
3)
What are the types of bacterial flagella distribution?
- Monotrichous
- Amphitrichous
- Lophotrichous
- Peritrichous
4) What are the differences and similarities between cell wall structure of G+ and Gbacteria?
- Similar: both have cytoplasmic membrane and Integral protein
- Differences:
Gram-positive
Gram-negative
+ Cell wall has thicker layer of
peptidoglycan
+Lipoteichoic acids that anchor the
wall to the cytoplasmic membrane
+ Cell wall has a thin layer of
peptidoglycan
+ An outer membrane composed of
lipopolysaccharide, phospholipids,
and proteins.