Bacterial Cell Structure

Question 1

Compartmentalized with membrane-encased organelles with true nucleus and nuclear membrane

Answer 1

Eukaryotes

Question 2

Non-compartmentalized type of cell

Answer 2

Prokaryotes

Question 3

Many are specialized in hostile environments similar to prokaryotes in that they do not have a nuclei

Answer 3

Archaeobacteria

Question 4

Cytoplasmic Structures of Bacteria:

N, R, CG, ES/S

Answer 4

Nucleoid– DNA appears as a diffuse nucleoloid without nuclear membrane
Ribosomes– FREE (70s in size)
Cytoplasmic Granules– store energy sources; produce energy if lack of resource
Endospores/Spores– resist harsh environmental conditions

Question 5

Bacterial Genome is commonly: ss or ds

Answer 5

Double Stranded. Commonly double stranded, circular, coiled, compact, more than 1 chromosome in some

Question 6

Bacterial Ribiosome size is commonly: 70s or 80s

Answer 6

70s in size. 2 subunits (50s & 30s)

80s is for Eukaryotes

Question 7

Why are spores formed?

Answer 7

To resist harsh/ extreme environment

Question 8

Bacterial Plasma Membrane is composed of and functions as:

Answer 8

Bilayered Lipoprotein.

Plasma Membrane for bacteria functions as inflow & outflow of enzymes. It serves as the site of electron transport chain for energy production.
Since bacteria has no mitochondria, enzyme systems in outer membrane of the mitochondria is found in the plasma membrane of bacteria.

Question 9

Cell Envelope Structures:

PM, CW, C, CA (F,P)

Answer 9

Plasma Membrane– bilayered lipoprotein (NOT PHOSPHOLIPID BILAYER *not same)
Cell Wall– (g+, g-, acid fast)
Capsule– virulence factor; help evade phagocytosis
Cell Appendages– Flagella (locomotion) & Pilli (attachment & gene exchange)

Question 10

What is the function and importance of capsule?

Answer 10

Virulence factor, Help evade Phagocytosis

Keep moisture in cells & resistant to drying. Protects Bacteria

Question 11

What is the difference of Pili/ fimbriae & flagella

Answer 11

Pili is used for attachment & gene exchange while flagella is used for locomotion

When a bacteria is referred as “non-motile”– no flagella

Question 12

Flagellar Arrangement:

Monotrichous

Answer 12

1 polar flagellum (==)~

Question 13

Flagellar Arrangement:

Amphitrichous

Answer 13

(both sides) 1 flagellum at each end of cell ~(==)~

Question 14

Flagellar Arrangement:

Lophotrichous

Answer 14

(tuft) 2 or more flagella at 1 or 2 poles of cell

(==)~~~~~
~~~~~(==)~~~~~

Question 15

Flagellar Arrangement:

Peritrichous

Answer 15

(around) flagella distributed OVER entire cell

~~(==)~~

Question 16

Principal Component of g+ cell wall

Answer 16

Peptidoglycan Layer

Question 17

Unique to g+ cell wall

Answer 17

Teichoic Acid & Lipoteichoic Acid

Question 18

2 Layers of g- cell wall:

IPL, OM

Answer 18

Inner Peptidoglycan Layer

Outer Membrane

Question 19

Has a thin Peptidoglycan Layer

Answer 19

g-

Question 20

Components of outer membrane of g- bacteria:

LPS, CP, AOSP, LA/E

Answer 20

Lipopolysaccharide
Core Polysaccharide
Antigenic O-specific polysaccharide
Lipid A/ endotoxin

Question 21

what structure makes g+ different from g- bacteria?

Answer 21

Peptidoglycan layer

g+ (thick)
g- (thin)

Question 22

Has a thick Peptidoglycan Layer & no outer membrane

Answer 22

Acid-Fast Cell Wall

Question 23

When Acid fast bacteria is stained with gram stain, will it appear g- or g+?

Answer 23

g+

They retain carbolfuchsin & not decolorized by acid alcohol

Question 24

What makes acid fast cell walls unique?

Answer 24

Mycolic Acid

Question 25

Mycoplasma & Ureaplasma lacks…

Answer 25

Cell wall

Their cell membrane contains sterols

Question 26

Rod-like shaped bacteria. Largest Variety

Answer 26

Bacilli

Question 27

Spherical Shaped bacteria

Answer 27

Cocci

Question 28

Spiral and flexible bacteria

Answer 28

Spirochetes

Question 29

shorter than the usual bacillus and sometimes mistaken as cocci

Answer 29

Coccobacillus

Question 30

comma shaped bacillus

Answer 30

vibrio

Question 31

Spiral and rigid with polar flagella

Answer 31

Spirilla