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Flashcards in Prokaryotes Deck (52):
1

Name the 2 prokaryotic domains

1. Archaebacteria
2. Eubacteria

2

_____________ are found in harsh environments

Archaebacteria

3

Examples of harsh environments in which archaebacteria are found

Very saline places; hot place

4

What group is referred to as the true bacteria

Eubacteria

5

What cell structures are lacking in prokaryotes?

Organelles

6

Do bacteria have ribosomes like other types of cells?

Yes

7

Describe the genetic material of bacteria. Where is it found?

DNA; it floats in the cytoplasm

8

What surrounds the outside of all bacterial cells?

Capsule

9

Cell walls of true bacteria contain _____________

peptidoglycan

10

Beside the circular chromosome, where else can DNA be found inside a bacterial cell?

cytoplasm

11

What is the size of most bacterial cells?

1-10 um

12

most bacteria act as a _________

decomposer

13

How can some bacteria be harmful?

diseases

14

What does motile mean?

can move

15

Motile bacteria may have one or more _______ for movement

flagella

16

What are bacterial pili?

Hair-like appendages used for reproduction

17

What are pili used for?

gene transfer and sticking to surfaces

18

What is spiral shaped bacteria?

spirillum

19

What is rod shaped bacteria?

bacilli

20

what is round shaped bacteria?

cocci

21

How do the walls of archaebacteria differ from true bacteria?

do not contain peptidoglycan

22

How do the cell membranes of archaebacteria differ from true bacteria?

archaebacteria cell membranes contain hydrocarbon instead of fatty acids

23

do archaebacteria and eubacteria have the same ribosomes?

no

24

Do archaebacteria require oxygen?

no

25

Methanogens live in _______ environments. What is lacking in this environment?

reduced; oxygen

26

How do methanogens get their energy?

methanogenesis

27

What is methanogensis?

the process in which a methanogen uses carbon as an electron accepter to produce methane

28

The _________ live in very salty environments

halophiles

29

___________ live in extremely hot environments

Thermophiles

30

Describe Gram staining

a method of differentiating bacterial species into two large groups by use of stain

31

Describe the cell wall of Gram positive bacteria

thick peptidoglycan layer in the cell wall

32

What color is the cell wall of Gram positive bacteria stained?

crystal violet

33

Describe the cell wall of Gram negative bacteria

thin peptidoglycan layer

34

What color is the cell wall of Gram negative bacteria stained?

red or pink

35

5 modes of nutrition in bacteria?

Autotrophs, Heterotrophs, Phototrophs, Chemotrophs, Lithotrophs

36

How do autotrophs get their nutrition?

They obtain their nutrition from inorganic compounds. Autotrophs will use hydrogen sulfide, ammonia or hydrogen gas to reduce carbon into necessary sugars.

37

How do heterotrophs get their nutrition?

organic sources of carbon such as sugars, fats and amino acids

38

How do phototrophs get their nutrition?

Phototrophic bacteria absorb light energy, then utilize this in photosynthesis to create cellular energy

39

How do chemootrophs get their nutrition?

These bacteria obtain chemical energy from their surroundings and convert it into ATP

40

How do lithotrophs get their nutrition?

use reduced inorganic compounds as the electron donor (H-donor) in anaerobic or aerobic respiration.

41

Explain obligate aerobes:

An obligate aerobe is an organism that requires oxygen to grow. Through cellular respiration, these organisms use oxygen to metabolise substances, like sugars or fats, to obtain energy.

42

Explain obligate anaerobes:

Obligate anaerobes are microorganisms that are killed by normal atmospheric concentrations of oxygen

43

Explain facultative anaerobes:

A facultative anaerobe is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation or anaerobic respiration if oxygen is absent.

44

How do bacteria reproduce asexually?

binary fission

45

How do bacteria reproduce sexually?

genetic recombination

46

How does conjugation work

Conjugation is the direct transfer of DNA from one bacterial cell to another bacterial cell. The transferred DNA is a plasmid, a circle of DNA that is distinct from the main bacterial chromosome. The F plasmid is similar to a virus or a transposon in its ability to move independently of the main chromosome. The transfer of the plasmid take advantage of the complementary nature of double stranded DNA. One strand of the plasmid is transferred and the other remains in the original cell. Both strands have the complementary stranded added so that each cell ends up with a complete plasmid.

47

How do the new cells compare to each other after conjugation?

they are identical

48

How long can an endospore survive?

millions of years

49

Why are endospores such a problem in health care facilities and in the canning industry.

Dormant bacteria can suddenly become active after years of being inactive.

50

What are Pathogens?

Bacteria that can cause disease

51

what are toxins?

poisons

52

Difference between endotoxin and exotoxin

Exotoxins are toxic substances secreted by bacteria and released outside the cell. Whereas Endotoxins are bacterial toxins consisting of lipids that are located within a cell.