CHAPTER 3.1-3.2

Question 1

Where is DNA in bacteria and archaea

Answer 1

Cytoplasm

Question 2

Bacterial cell walls are made of _____

Answer 2

Peptidoglycan

Question 3

T/F: Bacteria and archaea have cell wals that are different tan any eukaryotic structure

Answer 3

TRUE

Question 4

Bacteria and archaea _____ have organelles like eukaryotes

Answer 4

DO NOT

Question 4

what is the cytoplasm made of ?

Answer 4

mostly water (80), but it also contains dissolved ions, nutrients, enzymes and various other molecules

Question 5

What are the other structures in bacterial cells

Answer 5

• Cell wall
• cytoplasmic membrane
• cytoplasm
• chromosomes
• ribosomes
• flagella
• pili and fimbriae
• plasmids

Question 5

Flagella and its function

Answer 5

Flagella- long, whip-like appendages that protrude from the cell body of bacteria and archaea
Function- responsible for mobility

Question 6

Chemotaxis

Answer 6

Movement of bacteria toward or away from a chemical stimulus

Question 6

What makes up a ribosome?

Answer 6

Ribosomal DNA and proteins

Question 7

Positive chemotaxis

Answer 7

towards the attractant (nutrients)

Question 8

Negative chemotaxis

Answer 8

away from the repellant (toxins)

Question 9

Running

Answer 9

when the flagella rotate in one direction, allows the bacteria to move in a straight line

Question 10

Tumbling

Answer 10

when the flagella reverse rotation, causing the bacteria to change direction

Question 11

Pilus

Answer 11

• found in gram negative bacteria
• facilitates genetic diversity through DNA transfer
• longer and few in number

Question 12

Fimbria

Answer 12

• protein subunits
• found in both gram negative and gram positive bacteria
• functions to adhere to surfaces/ promotes colonization
• shorter and more numerous

Question 13

S Layer

Answer 13

• referred to as the armor of bacteria
• single layer of proteins or glycoproteins
• provides structural support and protection
• found in more extreme environmental conditions

Question 14

Glycocalyx

Answer 14

• polysaccharide based coating (slime layer or capsule) —> bacterial
• involved in adhesion to surfaces and protextion against desiccation

Question 15

Slime layer

Answer 15

• made of glycoproteins
• loosely attached to bacterial surface
• less organized
• helps bacteria evade host immune system but not as effective as capsule

Question 16

Capsule

Answer 16

• Firmly attached and organized
• Composed of polysaccharides, in some cases polypeptides
• provides a strong defense against phagocytosis, desiccation and immune evasion

Question 17

Main difference between: Slime layer and capsule

Answer 17

-Slime layer is loosely attached and more diffuse
- Capsule is firmly attached and more organized. Also provides stronger protection

Question 18

Main difference between: S Layer and Glycocalyx

Answer 18

S Layer is a crystalline protein layer that offers structural integrity and protection
Glycocalyx is a polysaccharide based coating used for adhesion, protection and immune evasion

Question 19

Main difference between Pilus and Fimbriae

Answer 19

Pili are longer, fewer and involved in DNA conjugation/mobility
Fimbriae are shorter, more numerous and specialized for adhesion

Question 20

Biofilm

Answer 20

Complex, multilayer community of bacteria that adhere to surfaces and are embedded in a self-produced matrix of extracellular polymeric substances

Question 21

Properties of Gram-negative bacteria

Answer 21

• cell wall is thick
• periplasmic space between the cell wall and cell membrane
• another layer