Chapter 28

Question 1

Peptidoglycan

Answer 1

Type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short peptides

Question 2

Gram stain

Answer 2

Stain used to categorize bacteria by cell wall composition

Question 3

Gram-positive

Answer 3

Bacteria have relatively simple walls composed of a thick layer of peptidoglycan

Question 4

Gram-negative

Answer 4

Walls have less peptidoglycan and are more complex with an outer membrane containing lipopolysaccharide

Question 5

Why is penicillin effective

Answer 5

It inhibits peptidoglycan cross linking reducing effectiveness of cell wall

Question 6

Capsule

Answer 6

Dense layer of polysaccharide or protein that surrounds the cell wall protecting it and allowing it to adhere to surfaces

Question 7

Slime layer (capsule)

Answer 7

Not well organized

Question 8

Endospore

Answer 8

Thick coated resistant offspring cell produced by some bacterial cells when they are exposed to harsh conditions

Question 9

Fimbria

Answer 9

Hairlike appendages of prokaryotic cell that helps it adhere to substrate or other cells

Question 10

Exaptions

Answer 10

Process where structures originally adapted for one function take on new functions through evolution

Question 11

Plasmid

Answer 11

Small, circular, DNA that carries accessory genes separate from those of a bacterial chromosome

Question 12

Horizontal gene transfer

Answer 12

Movement of genes from one species to another

Question 13

Transformation

Answer 13

Process where a cell changes genotype due to uptake of foreign DNA

Question 14

Transduction

Answer 14

Bacteriophage transmit DNA from one cell to another

Question 15

Conjugation

Answer 15

Direct transfer of DNA between 2 cells that are temporarily joined

Question 16

F-factor

Answer 16

DNA segments that can form pili for conjugation and associated functions required for the transfer of DNA from donor to recipient

Question 17

F plasmid

Answer 17

Plasmid with f-factor

Question 18

R plasmid

Answer 18

Plasmid with genes that resist antibiotics

Question 19

Obligate aerobes

Answer 19

Must use oxygen for respiration

Question 20

Obligate anaerobes

Answer 20

Are poisoned by oxygen so must use other molecules for respiration

Question 21

Facultative anaerobes

Answer 21

Can use oxygen if it’s present but can also use anaerobic respiration

Question 22

How do prokaryotes help the environment by fixing nitrogen

Answer 22

They can convert nitrogen into ammonia which is able to be used by plants

Question 23

Heterocysts

Answer 23

Specialized cells that engage in nitrogen fixation in some filamentous cyanobacteria

Question 24

Biofilms

Answer 24

Surface coating colony of one or more species of unicellular organisms that engage in metabolic cooperation

Question 25

Extremophiles

Answer 25

prokaryotes who live in extreme environment

Question 26

Extreme halophiles

Answer 26

Live in highly saline environments

Question 27

Extreme thermophiles

Answer 27

Live in hot temperatures

Question 28

Methanogens

Answer 28

Archaea who release methane as a byproduct of-product of how they obtained energy

Question 29

Mutualism

Answer 29

Ecological relationships where both species are benefited

Question 30

Commensalism

Answer 30

Interaction where one species is receiving benefit but the other is not benefited or harmed

Question 31

Parasitism

Answer 31

Symbiont feeds on host’s nutrients

Question 32

Exotoxins

Answer 32

Protein secreted by organisms that are toxic and can cause symptoms after organism is dead

Question 33

Endotoxins

Answer 33

Toxic component of gram-negative bacteria’s outer membrane that’s released only when bacteria die

Question 34

Antibiotic that inhibit protein synthesis

Answer 34

Tetracycline, and erythromycin

Question 35

What do denitrifying bacteria do

Answer 35

Release ammonium back into the air as Nitrogen gas