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Flashcards in Chapter 4. Deck (73):
1

Bacteria

Bacteria - simple, single-celled organisms, DNA not enclosed, Prokaryotic, peptidoglycan cell wall, binary fission (split into 2 equal parts), contain flagella

2

Distinguish a genus from a specific epithet.


a genus: Capitalized and
a specific epithet (species): not capitalized

3

Archaea

prokaryotic, peptidoglycan cell wall, found in extreme environments; pathogenic in humans

4

Fungi

Eukaryotic, nucleus containing DNA, uni/multi cellular, photosynthesis, chitin cell wall, sexually or asexual repoduction

5

Protozoa

nicellular, eukaryotic, move using pseudopods, flagella or cilia, photosynthesis, sexual/asexual reproduction

6

Algae

eukaryotic, photosynthetic, unicellular, cellulose cell wall.

7

Viruses

acellular, simple, one type of nucleic acid, must have host to survive.

8

Multicellular Animal Parasites/Helminths

eukaryotic, (flat/round worms)

9

Which groups of microbes are prokaryotes?

Bacteria and archaea

10

Which are eukaryotes?

Algae, Fungi, Protozoa

11

What are the three domains?

Bacteria, Archaea, Eukarya

12

Explain the importance of observations made by Hooke and van Leeuwenhoek.

He discovered life's smallest structural units called 'cells'; discovered live microorganisms

13

What is the cell theory?

all living things are composed of cells

14

Compare spontaneous generation and biogenesi

Belief that some forms of life could arise spontaneously from nonliving matter;

15

What evidence supported spontaneous generation?

Redi's experiment with one covered and one uncovered meat jar producing maggots proved that this could not occur spontaneously

16

Identify the contributions to microbiology made by Needham,

1

17

Compare and contrast the overall cell structure of prokaryotes and eukaryotes.

Compare: both contain nucleic acids, proteins, lipids, and carbs; same chemical reactions to metabolize food, build proteins, and store energy.
Contrast: structure of cell walls and membrane, and absence of organelles

18

What is the main feature that distinguishes prokaryotes from eukaryotes?

Prokaryotes: DNA not enclosed, singular arranged chromosomes, DNA not associated with histones, lack membrane-enclosed organelles, cell wall contain polysaccharide peptidoglycan, divide by binary fission
Eukaryotes: DNA in nucleus, muti chromosomal, histones, membrane-enclosed organelles, cell wall simple, mitosis

19

Identify the three basic shapes of bacteria.

coccus- round, bacillus- rod shaped, spiral- spiral

20

How would you be able to identify streptococci through a microscope?

strepto- chains, cocci- round

21

Describe the structure and function of the glycocalyx.

sugar coat surrounding a cell. made of viscous (sticky), gelatinous polymer that is externa to the cell wall. composed of polysaccharide, polypeptide, or both.
-organized and firmly attached to cell wall: capsule
-unorganized and loosely attached: slime layer

22

Why are bacterial capsules medically important?

they protect the cell from phagocytosis by the cells of the host. this is bad because it makes the bacteria able to cause disease in the host

23

Differentiate flagella, axial filaments, fimbriae, and pili.

Flagella: prokaryotic cells; long filamentous appendages that propel bacteria
Axial filaments: found on spirochetes; bundles of fibrils that arise at the ends of the cell beneath an outer sheath and spiral around the cell/spiral motion
Fimbriae: involved in forming biofilms; help bacteria adhere to epithelial surfaces
Pili: motility and DNA transfer (conjugation)

24

How do bacteria move?

Flagella, Axial filaments, fimbriae, and pili

25

Compare and contrast the cell walls of gram-positive bacteria, gram-negative bacteria, acid-fast bacteria, archaea, and mycoplasmas.

Gram positive: many layers of peptidoglycan, thick, rigid structure; contain teichoic acids
Gram negative: thin layer of peptidoglycan, outer membrane made of lipopolysaccharides, lipoproteins, and phospholipids.
Acid-fast bacteria: high concentration of hydrophobic waxy lipid (mycolic acid), thin layer of peptidoglycan
Archaea: may have no cell wall, or unusual walls of polysaccharides and proteins- no peptidoglycan.
Mycoplasmas: no cell wall

26

Why are drugs that target cell wall synthesis useful?

Bacterial cell walls are made of different material as Eukaryotic cells

27

Differentiate protoplast, spheroplast, and L form.

Protoplast: a gram-positive bacterium or plant cell treated to remove the cell wall
Spheroplast: gram-negative bacterium treated to damage the cell wall; spherical cell
L form: prokaryotic cell that lack a cell wall; can return to walled state

28

How do protoplasts differ from L forms?

L forms can return to a walled state

29

compare and contrast overall cell structure of prokaryote and eukaryote cells

prokaryote:
-one singular chrosome, not in a membrane
-no histones (naked DNA)
-no membrane bound organelles
-peptidoglycan cell walls if bacteria
-pseudomerian cell walls if archaea
-divide by binary fission

eukaryote:
-paired chromosomes, in nuclues
-histones around dna
-membrane bound organelles
-polysaccharide cell walls
-mitotic spindle

30

what is the main feture that distinguishes prokaryotes from eukaryotes?

the nucleus!

31

identify the three basic shapes of bacteria

-baccilus- rod shaped
-coccus- spherical
-sprial: spirillum (one kink), vibro(comma shaped), spirochete (multiple kinks)

32

arrangements of bacteria

pairs- di
clusters- staph
chains- strep

33

how would you be able to identify streptococci through a microscope

- it would look like a chain of spheres under the microscope

34

describe the structure and function of the glycocalyx in prokaryotic cells

-outside the cell wall
-usually sticky and firmly attached
-organized= capsule, prevents phagocytosis
-unorganized= slime layer, allows cells to attatch, protects against dehydration, nutrient loss and antibiotics

35

flagella

flagella
-outside the cell wall
-made of chains of protein flagellin
-attached to a protein hook
-anchored to the wall and membrane by the basal body- gram negative have 2 pairs , postive have 1 pair

36

Pili

pili
-used for reproduction, sends copies of DNA to another cell
-1 or 2 per cell
-provide gliding and twitching motility

37

fimbriae

-allow attachment
-found in gram positive cells
-anchor cells to something so they can invade
-lots per cell

38

axial filaments

-also called endoflagella
-in spirochetes
-anchored to one end of the cell
-rotation causes cell to move
-located inside of the cell

39

how do bacteria move?`

running and tumbling by flagella
-running- bacteria moves in one direction for a lenght of time
-tumbles- periodic, abrupt, random changes in direction

40

the bacteria cell wall

complex & semiridiged
-made of peptidoglycan (polymer made up of NAG and NAM during a dehydration syntehsis reaction)

41

gram positive vs gram negative cell wall

positive:
-up to 25 layers of peptidoglycan
-nag and nam backbone linked together with polypeptides (amino acids)
-teichoic acid forms beams that go up and down to hold the structure together
-side chains up and down, cross bridges across
-stacked on top of membrane
negative:
-one layer of peptioglycan
-doesn't contain and cross bridges or side chains, no peptide bonds
-sandwiched between two membranes

42

how does the gram stain work on the cells

gram positive
-alcohol dehyrdates the peptiodglycan
-crystals dont leave

gram negative
-alcohol dissolves outer membrane and leaves holes in peptidoglycan, crystals wash out

-lysosomes effect cross bridges, so they only effect postive

43

acid fast bacteria cell walls

-like gram positive
-wazy lipid bound to peptidoglycan, prevents uptake of dyes

44

mycoplasmas vs archaea cell wall

mycoplasmas:
-lack cell walls
-sterols in plasma membrane

archaea:
-wall less or walls of pseudomurine( lack NAM and d amino acid)

45

differentiate protoplast, spheroplast, and l form

*result from damage to the cell wall
protoplast- wall less gram positive cell
spheroplast- wall less gram negative cell
* both susceptible to osmotic lysis( burst in pure water )
L form- wall less cells that swell into irregular shapes

46

describe the structure, chemistry, and functions of the prokaryotic plasma membrane

-consist primarly of phospholipids
-lipid bilayer- produces and repairs cell wall, just inside cell wall
-peripheral proteins- proteins just inside bilayer
-intergral proteins- intergrated in cell wall
-transmembrane- across membrane
-selective permebility- allows passage of some molecules
-important to the breakdown of nutrients and the production of energy
-contains enzymes capable of catalyzing the chemical reactions that break down the nutrients and produce atp

47

which agents can cause injury to the bacterial plasma membrane?

-alcochols, quaternary ammonium( detergents), and antibiotics causes leakage of cell contents
-takes off outer membrane layer

48

forms of passive transport

*doesn't require energy
simple diffusion:
-movement of a solute from high to low concentration
-nonpolar substances are easy to diffuse
-happens until equilibrium is reached

facilitated diffusion:
-solutes combines with a transporter protein in the membrane
-polar substances use this

osmosis:
-the movemnt of water from high to low concentration
-use aquaporins- water channels

49

active transport

*requires a transporter protein and atp
-ions, amino acids, simple sugars
-goes against concentration gradient

50

identify the functions of the nucleoid and ribosomes in prokaryotic cells

nucleiod:
-contains a single, long, continuous, circular arranged thread of dna-- bacterial chromosome
-some bacteria also have small circular double stranded dna molecules called plasmids--plasme membrane proteins, can be transfered from cell to cell

ribosomes:
-sites of protein synthesis
-composed of 2 subunits, consists of protein and a type of rna- rRNA
-called 70s ribosomes

51

where is the dna located in a prokaryotic cell

dna in prokaryotic cells are found in the nucleiod

52

what is the general function of inclusions

reserve deposits, generally cells and accumulate certain nutrients and use them when the environment is deficient

53

identify the function of four inclusions

1. metachormatic granules- large inclusions called volutin- reserve of inorganic phosphate that can be used in the synthesis of ATP
2. polysaccharide granules- consists of glycogen and starch
3. lipid inclusions- polymer poly b and acid
4. sulfur granules- genus thiobacillus, use sulfur for energy
5. carboxysomes- enzymes ribulose, photosnthetic bacteria use CO2 as source of carbon and require this enzyme
6. gas vacuoles- hollow cylinders covered by protein. maintain buoyancy so that cells can remain at a depth of water
7. magnetosomes- inclusions of iron oxide

54

describe the functions of endospores, sporulation, and endospore germintaion

endospores- resting cells, resistant to desiccation, heat, and chemicals. highly durable dehydrated cells with thick walls, found in gram positive bacteria
sporulation- endospore formation with a vegetative cell, takes several hours. forms spore around DNA of cell
endospore germination- endospore returning to its vegetative state, triggered by physical or chemical damage to the endospore coat

55

under what conditions do endospores form?

they form under harsh environments, form spores around DNA. cell dies off and DNA remains protected. can lye dormant for several years

56

differentiate prokaryotic and eukaryotic flagella

prok- double membrane, give cells movement. made up of the filliment- flagillan, the hook,and the basal body- rod with a series of rings
euk- structures that extend from the cell, anchored to plasma membrane by basal body- consists of the 9+2 array of microtubles- made of tubulin

57

difference between eukaryotic flagella and cillia

cell walls
prok- made of peptidoglycan, can be gram positive or gram negative
-complex and ridgid
euk- much more simple, algae- cellulose, fungi-chitin, yeast- glucan and mannan
glycocalyx
prok- slime layer or capsules
euk- layer of material containing sticky carbs
-strenghtens cell surface, helps attach cells together, contributes to cell to cell recognition

58

compare and contrast prok and euk plasma membranes

-very similar in function and basic structure, different in types of proteins found in the membranes
euk- contain carbs, which serve as attachment sites for bacteria and as receptor sites that assume a role in cell to cell recognition
-contain sterols

59

euk endocytosis

-segment of the plasma membrane surrounds a particle or large molecule, encloses it, and brings it into the cell
three types:
1. phagocytosis-pseudopods extend and engulf particles
2. pinocytosis- membrane folds inward, brings in fluid and dissolves substances
3.receptor-mediated endocytosis- substance binds to receptors in the membrane, when binding occurs, membrane folds inward. one way viruses can enter cell

60

compare and contrast prok and euk cytoplasm

euk-contains a complex internal structure, consisting of exceedingly small rods and cylinders. they form the cytoskeleton
-important enzymes are located in organelles
prok- enzymes are free floating in cytoplasm

61

compare the structure and function of euk and prok ribosomes

both- protein synthesis
prok- called 70s ribosomes, made up of 50s and 30s free floating
euk- somewhat larger and denser than prok, called 80s ribosomes made up of 60s and 40s subunits. can be free floating or attached to the rough er
*because of the differences, microbiol cells can be killed by antibiotics without harming the host cells

62

endoplasmic reticulum

extensive network of flattened membranous sacs/tubules called ccisterne
-rough: continous with nuclear envelope. studded with ribosomes. factory for synthesizing secretory proteins and membrane molecules
-smoth: network of membrane tubules. contains unique enzymes. synthesizes phospholipids and fats and sterols

63

golgi complex

proteins synthesized in rough er transported to golgi. modified and trasnported to the plasma membrane or are stored

64

lysosomes

formed in the golgi. contain 40 different kinds of digestive enzymes. single membrane and lack interal structure

65

vacuoles

space/ cavity in cytoplasm. derived from golgi. temporary storage. helps bring food into cell. store wastes and poisions. take up water

66

mitochondria

double membrane. provides enormus surface area for chemical rreactions for chemical reactions. powerhouse of the cell- ATP production. 70s ribisomes.
-machinery for replicate, transcribe, and translate info incoded by their DNA--can reproduce on their own

67

chloroplasts

algae and gree plants. photosynthesis. contain thylakoids and 70 ribisomes

68

peroxisomes

from by the divison of preexisting peroxisomes. contain enzymes that can oxidize various organic substances
-protects other parts of cell from hydrogen peroxide

69

centrosome

organizing center for mitioc spindles- pericentriolar material

70

discuss evidence that supports the endozymbiotic theory of euk evolution

theory- larger bacterial cells lost their cell walls and engulfed smaller bacteria cells
-both mitochondria and chloroplasts resemble bacterian size and shape.
-contain circular DNA and can reprodce on their own
-ribosomes in them resemble prok. ribosomes .
-same antibiotics that inhibit protein synthesis in ribosomes in bacteria also inhibit protein synthesis in mito. and chloro.

71

compare the structure of euk. nuclues and prok. nucleiod

euk nucleus- spherical, largest structure of the cell, contains almost all DNA
-surrounded by a double membrane nuclear envelope with nuclear pores for communication
-DNA wrapped in histones

prok nuleoid- single circular DNA-bacterial chromosome and plasmids.
-no histones or nuclear envelope

72

compare the structure and function of euk and prok ribosomes

both- protein synthesis
prok- called 70s ribosomes, made up of 50s and 30s free floating
euk- somewhat larger and denser than prok, called 80s ribosomes made up of 60s and 40s subunits. can be free floating or attached to the rough er
*because of the differences, microbiol cells can be killed by antibiotics without harming the host cells

73

the antibiotic erythromycin binds with the 50s portion of a ribosome. what effects does this have on a prok and euk cell?

prok- will kill the cells
euk- doenst effect it at all because euk cells do not have a 50 s portion of the ribosomes