MICR 290 EXAM 5 QUESTIONS WITH 100%
CORRECT ANSWERS!!
Bacterial Cell Walls: Peptidoglycan
A complex polysaccharide composed of two types of alternating sugar molecules, called:
N-acetylglucosamine (NAG)
&
N-acetylmuramic acid (NAM)
Both sugars are structurally similar to glucose
How do Prokaryotic cells Reproduce
All reproduce asexually via three main methods:
Binary fission (most common form of asexual reproduction)
Snapping division (variation of binary fission)
Budding (bud formation)
Binary fission
1-Cell replicates its DNA
2-The cytoplasmic membrane elongates, separating DNA molecules
3-Cross wall forms; membrane invaginates
4-Cross wall forms completely
5-Daughter cells may separate
,Most common form of asexual reproduction
Snapping fission
Only the inner portion of the cell wall is deposited across the diving cell
Causes tension to put on the outer layer of the old cell wall and eventually the outer wall "snaps"
at its weakest point
Daughter cells remain hanging together, held at an angle by a small remnant of the outer wall
that acts as a hinge
Snapping fission (occurs)
In some Gram + species
Budding
1-DNA, which is attached to the cytoplasmic membrane, is replicated
2-Cell elongates to form a bud; the expanding cytoplasmic membrane carries one attached DNA
molecule in the bud
3-Young bud is formed
4-Young bud separates to form a daughter cell
Bacteria Cellular Shapes and Arrangements
-Coccus
-Coccobacillus
-Bacillus
,-Vibrio
-Spirillum
-Spirochete
-Pleomorphic
-Star
Arrangements result from 2 aspects of division during fission
Cell walls help give bacterial cells their characteristic shapes
Arrangements result from two aspects of division during binary fission:
1-The planes in which cells divide during binary fission
2-Whether or not the daughter cells separate completely or remain attached to each other
Bacteria Cellular Shapes and Arrangements (Coccus Arrangments)
Diplococci (2)
Streptococci (short chain)
Tetrads (square)
Sarcinae (cube)
Staphylococci (cluster)
Coccus (Diplococci)
cocci cells that remain attached in pairs
, Coccus (Streptococci)
cocci that form long chains
Coccus (Tetrads)
cocci that divide in two planes and remain attached
Coccus (Sarcinae)
cocci that divide in 3 planes to form cuboidal packets
Coccus (Staphyloccocci)
cocci that look like bunches of grapes and form when the planes of cell division are random
Bacteria Cellular Shapes and Arrangements (Coccobacillus)
Bacteria Cellular Shapes and Arrangements (Bacillus Arrangement)
Bacilli are less varied in their arrangements than cocci because they divide transversely
(perpendicular to the long axis)
-Single
-Diplobacilli
-Streptobacilli
-Palisade
-V-shape
Bacillus (Single bacillus)
Bacillus (Diplobacilli)
Bacillus (Streptobacilli)
Bacillus (Palisade)
CORRECT ANSWERS!!
Bacterial Cell Walls: Peptidoglycan
A complex polysaccharide composed of two types of alternating sugar molecules, called:
N-acetylglucosamine (NAG)
&
N-acetylmuramic acid (NAM)
Both sugars are structurally similar to glucose
How do Prokaryotic cells Reproduce
All reproduce asexually via three main methods:
Binary fission (most common form of asexual reproduction)
Snapping division (variation of binary fission)
Budding (bud formation)
Binary fission
1-Cell replicates its DNA
2-The cytoplasmic membrane elongates, separating DNA molecules
3-Cross wall forms; membrane invaginates
4-Cross wall forms completely
5-Daughter cells may separate
,Most common form of asexual reproduction
Snapping fission
Only the inner portion of the cell wall is deposited across the diving cell
Causes tension to put on the outer layer of the old cell wall and eventually the outer wall "snaps"
at its weakest point
Daughter cells remain hanging together, held at an angle by a small remnant of the outer wall
that acts as a hinge
Snapping fission (occurs)
In some Gram + species
Budding
1-DNA, which is attached to the cytoplasmic membrane, is replicated
2-Cell elongates to form a bud; the expanding cytoplasmic membrane carries one attached DNA
molecule in the bud
3-Young bud is formed
4-Young bud separates to form a daughter cell
Bacteria Cellular Shapes and Arrangements
-Coccus
-Coccobacillus
-Bacillus
,-Vibrio
-Spirillum
-Spirochete
-Pleomorphic
-Star
Arrangements result from 2 aspects of division during fission
Cell walls help give bacterial cells their characteristic shapes
Arrangements result from two aspects of division during binary fission:
1-The planes in which cells divide during binary fission
2-Whether or not the daughter cells separate completely or remain attached to each other
Bacteria Cellular Shapes and Arrangements (Coccus Arrangments)
Diplococci (2)
Streptococci (short chain)
Tetrads (square)
Sarcinae (cube)
Staphylococci (cluster)
Coccus (Diplococci)
cocci cells that remain attached in pairs
, Coccus (Streptococci)
cocci that form long chains
Coccus (Tetrads)
cocci that divide in two planes and remain attached
Coccus (Sarcinae)
cocci that divide in 3 planes to form cuboidal packets
Coccus (Staphyloccocci)
cocci that look like bunches of grapes and form when the planes of cell division are random
Bacteria Cellular Shapes and Arrangements (Coccobacillus)
Bacteria Cellular Shapes and Arrangements (Bacillus Arrangement)
Bacilli are less varied in their arrangements than cocci because they divide transversely
(perpendicular to the long axis)
-Single
-Diplobacilli
-Streptobacilli
-Palisade
-V-shape
Bacillus (Single bacillus)
Bacillus (Diplobacilli)
Bacillus (Streptobacilli)
Bacillus (Palisade)
