Text Chapter 13: Microbes Flashcards Preview

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Flashcards in Text Chapter 13: Microbes Deck (22):
1

Characteristics of Bacteria and Archaea

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

2

Cell Division in Prokaryotes

binary fission

3

Gene Transfer in Prokaryotes

conjugation- transfer of DNA from donor to recipient via pilus

4

Unique Features of Archaea

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

5

Environments in which Archaea are Found

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

6

Chemoorganotrophes

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

7

Chemolithotrophes

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

8

Photoautotrophes

use CO2 and H2O, release O2

9

Photoheterotrophes

use carbon from organic compounds, do not release O2

10

Pathogenic Prokaryotes

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

11

Non-Pathogenic Prokaryotes

do not cause disease- decomposers, nitrogen-fixing bacteria

12

Characteristics of Protists

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

13

Asexual Reproduction on Protists

occurs by mitosis

14

Sexual Reproduction in Protists

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

15

Animal-like Protists

heterotrophic by ingestion

16

Plant-like Protists

photosynthetic, single-celled and multi-celled algae

17

Fungus-like Protists

heterotrophic by absorption

18

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

-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

19

Structure of Viruses

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

20

Why Viruses Lack the Properties of Life

they are dependent on their hosts’ metabolic machinery for replication

21

Replication of a DNA Virus

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

22

Replication of an RNA Virus

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