Bacterial Cell

Question 1

Macromolecules in Each Cell

Answer 1

proteins, polysaccharide, phospholipid, nucleic acid

Question 2

protein

Answer 2

amino acid

Question 3

3 architectural regions of a Bacterial cell

Answer 3

1. Appendages (attachments to the cell surface}
2. Cell envelope
3. Cytoplasmic region

Question 4

Appendages (attachments to the cell surface}

Answer 4

Flagella

Pili (or Fimbriae)

Question 5

Cell envelope

Answer 5

Capsule
Q Cell wall
Q Plasma membrane

Question 6

Cytoplasmic region

Answer 6

Nucleoid (DNA)
Q Ribosomes
Q Inclusions

Question 7

Threadlike (filamentous) protein appendages extending
outward from the plasma membrane and cell wall
» Slender, rigid structures, about 20nm across and up to
15 or 20 um long
» Allows a cell to move (swimming movement)

Answer 7

Flagella

Question 8

Flagellar distribution

Answer 8

Polar — one or more flagella arising from one or both
poles of the cell
o Peritrichous — flagella are spread fairly evenly over the
whole cell surface

Question 9

Short, fine, hairlike protein structures on the surfaces of

prokaryotic cells but not involved in motility

Answer 9

pili/fimbria

Question 10

— shorter and stiffer than flagella and slightly smaller in
diameter
- Most often involved in adherence of bacteria to surfaces,
substrates and other cells or tissues in nature.

Answer 10

fimbria

Question 11

similar to fimbriae, but not typically longer and only one or
a few pili are present on the surface of a cell
- Important in facilitating genetic exchange between cells in a
process called conjugation
- For pathogenic bacteria: important in the adhesion to
specific host tissues that leads to invasion

Answer 11

pili

Question 12

polysaccharide layers outside of the cell

Answer 12

capsule and slime layer

Question 13

if the layer is organized in a tight matrix that

excludes small particles, such as india ink

Answer 13

capsule

Question 14

less organized and is more easily deformed, does

not exclude small particles and is more difficult to see

Answer 14

slime layer

Question 15

formed when encapsulated microorganisms bind to

solid surfaces in nature (soil/water}

Answer 15

biofilms

Question 16

1. Mediate adherence of the cells to surface
2. Protect bacterial cells from engulfment by predatory protozoa,
   or from attack by antimicrobial agents of plant or animal origin
3. Protect cells from drying or desiccation

Answer 16

Functions of Capsule

Question 17

-Essential structure that protects the cell
protoplast from mechanical damage
and from osmotic rupture or lysis
-Important site for attack by antibiotics
» Provide ligands for adherence and receptor sites for drugs
or viruses

Answer 17

cell wall

Question 18

Species of bacteria can be divided into two major groups,

Answer 18

Gram-positive and Gram-negative based on gram staining

Question 19

who developed gram staining?

Answer 19

Hans Christian Gram,

Danish bacteriologist

Question 20

Differentiates bacteria by the chemical and physical

properties of their cell walls by detecting

Answer 20

peptidoglycan

Question 21

a rigid polysaccharide layer that
is primarily responsible for the
strength of the cell wall

Answer 21

peptidoglycan

Question 22

It is almost always the first
step in the preliminary
identification of a
bacterial organism

Answer 22

gram staining

Question 23

steps of gram staining

Answer 23

1. fixation
2. crystal violet
3. iodine treatment
4. decolorisation
5. counter stain with salfranin

Question 24

gram positive color

Answer 24

violet

Question 25

gram negative color

Answer 25

pink

Question 26

layers of gram positive cell

Answer 26

1. inner cytoplasmic membrane | 2. outer thick peptidoglycan layer (60-100% peptidoglycan)

Question 27

layers of gram negative cell

Answer 27

1. inner cytoplasmic membrane 2. thin peptidoglycan layer(5-10% peptidoglycan) 3,outer membrane with lipopolysaccharide

Question 28

low lipid content

Answer 28

gram positive

Question 29

high lipid content

Answer 29

gram negative

Question 30

no endotoxin no periplasmic space no porin channel

Answer 30

gram positive

Question 31

vulnerable to lysozyme and penicillin attack

Answer 31

gram positive

Question 32

endotoxin (LPS)- lipid A periplasmic space porin channel

Answer 32

gram negative

Question 33

resistant to lysozyme and penicillin attack

Answer 33

gram negative

Question 34

The most dynamic structure of a prokaryotic cell >» Made of 40 percent phospholipid and 60 percent protein Main functions: 1. Acts as a selective permeability barrier 2. Anchors proteins that are important for metabolic processes 3. Major site for energy conservation in the cell

Answer 34

cytoplasmic membrane

Question 35

The substance lying between the plasma membrane and the nucleoid and consist of an aqueous solution (gel-like) of three groups of molecules: 1. Macromolecules such as proteins (enzymes), MRNA and tRNA 2. Small molecules that are energy sources, precursors of macromolecules, metabolites or vitamins 3. Various inorganic ions and cofactors

Answer 35

Cytoplasmic | region

Question 36

One large irregularly shaped region that contains the chromosome or circular (some linear) double-stranded molecule of DNA (deoxyribonucleic acid). How large? When a bacterium such as E.coli is gently lysed the chromosomal DNA leaks out of the cell as a continuous molecule that is many times longer than the length of the cell.

Answer 36

nucleoid

Question 37

Small double-stranded circular DNA molecule within a cell Physically separated from a chromosomal DNA and can replicate independently Often carry genes that give their bacterial host a selective advantage for survival Can render bacteria drug-resistant, give them new metabolic abilities, make them pathogenic, or endow them with a number of other properties

Answer 37

plasmid

Question 38

____ are widely used as vectors in molecular cloning, serving to drive the replication of recombinant DNA sequences within host organisms

Answer 38

Artificial plasmid

Question 39

Made of both protein and ribonucleic acid (RNA Site of protein synthesis; matrix ribosomes synthesize proteins destined to remain within the cell, whereas the plasma membrane ribosomes make proteins for transport to the outside. Prokaryotes: 70S ribosomes, have dimensions of about 14 to 15 nm by 20 nm, and are constructed of a 50S and a 30S subunit

Answer 39

ribosome

Question 40

Distinct granules of organic or inorganic material that may occupy a substantial part of the cytoplasm » Usually used for storage (e.g., carbon compounds, inorganic substances, and energy}

Answer 40

Inclusion | bodies

Question 41

-A special resistant, dormant structure » Exhibit no sign of life » Formed in response to environmental signals that indicate a limiting factor for vegetative growth » Resistant to environmental stresses such as high temperature, irradiation, strong acids, disinfectants, etc.

Answer 41

endospores

Question 42

Under appropriate environmental conditions, _______ | germinate back into vegetative cells

Answer 42

endospores