Text Chapter 13: Microbes

Question 1

Characteristics of Bacteria and Archaea

Answer 1

prokaryotic, single-celled, categorized by shape, cell wall made of peptidoglycan, may be covered with capsule, uses flagellum for movement, many nutritional modes, unfolded plasma membranes for respiration of photosynthesis, single circular chromosome, may contain extrachromosomal plasmids, reproduce by binary fission, gene transfer by conjugation

Question 2

Cell Division in Prokaryotes

Answer 2

binary fission

Question 3

Gene Transfer in Prokaryotes

Answer 3

conjugation- transfer of DNA from donor to recipient via pilus

Question 4

Unique Features of Archaea

Answer 4

prokaryotes, unique lipid membranes, cell walls, flagella, ribosomal RNA

Question 5

Environments in which Archaea are Found

Answer 5

concentrated salt environments, swamps, hot environments, hot springs, vent communities, cow stomaches

Question 6

Chemoorganotrophes

Answer 6

use organic compounds for chemical energy and sources of carbon, heterotrophic, largest group of prokaryotes, including disease-causing bacteria

Question 7

Chemolithotrophes

Answer 7

use inorganic compounds for chemical energy, autotrophic, iron-oxidizing bacteria

Question 8

Photoautotrophes

Answer 8

use CO2 and H2O, release O2

Question 9

Photoheterotrophes

Answer 9

use carbon from organic compounds, do not release O2

Question 10

Pathogenic Prokaryotes

Answer 10

disease-causing organisms- some secrete exotoxins, others release endotoxins, some form endospores resistant to heat and desication

Question 11

Non-Pathogenic Prokaryotes

Answer 11

do not cause disease- decomposers, nitrogen-fixing bacteria

Question 12

Characteristics of Protists

Answer 12

eukaryotic, usually single-celled, live in moist environments, many nutritional modes, non-pathogenic and pathogenic, sexual and asexual reproduction

Question 13

Asexual Reproduction on Protists

Answer 13

occurs by mitosis

Question 14

Sexual Reproduction in Protists

Answer 14

involves the exchange of genetic material across a cytoplasmic bridge, following meiosis

Question 15

Animal-like Protists

Answer 15

heterotrophic by ingestion

Question 16

Plant-like Protists

Answer 16

photosynthetic, single-celled and multi-celled algae

Question 17

Fungus-like Protists

Answer 17

heterotrophic by absorption

Question 18

Key events in the vegetative, social, and sexual cycle of Dictyostelium

Answer 18

• Dictyostelium uses pseudopods for movement
• social cycle occurs when the bacterial supply is limited
• attracted to the social cycle by cAMP
• social cycle shows altruism
• sexual cycle shows cannibalism
• spores are produced from the fruiting body by mitosis and by the macro cyst by meiosis

Question 19

Structure of Viruses

Answer 19

caspid (container of protein), genetic material (DNA or RNA), plasma membrane (envelope), glycoproteins

Question 20

Why Viruses Lack the Properties of Life

Answer 20

they are dependent on their hosts’ metabolic machinery for replication

Question 21

Replication of a DNA Virus

Answer 21

virus enters the host cell, viral DNA is used to produce more genetic material and protein to form new viral particles

Question 22

Replication of an RNA Virus

Answer 22

virus carries reverse transcriptase enzyme that is used to make a DNA copy of the viral genetic material, the DNA copy is used to produce the new viral particles the bud from the surface of the host cell