Ek Lecture 3 - Microbiology

Front 1

capsid

Back 1

protein coat of virus that contains several hundred genes in the form of DNA or RNA

Front 2

viral envelope

Back 2

lipid-rich surrounding of viruses, either borrowed from the host cell membrane or synthesized in the host cell cytoplasm

Hint 2

typically contains virus specific proteins

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virion

Back 3

a mature virus outside the host cell

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host

Back 4

the cell that is being infected

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chemical receptor

Back 5

usually a specific glycoprotein on the host cell membrane

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bacteriophage

Back 6

a virus that infects bacteria

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bacteriophage tail

Back 7

after enzymes have digested a hole in the cell wall, nucleic acid is injected through tail

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endocyotic process

Back 8

cellular uptake of macromolecules and particulate substances by regions of the plasma membrane that surround the substance and pinch off to form an intracellular vesicle

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lytic infection

Back 9

viral/phage replication cycle resulting in the release of new phages by lysis and death of the host cell

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latent period

Back 10

the period from infection to lysis

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virulent virus

Back 11

one that reproduces only by a lytic cycle

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lysogenic infection

Back 12

phage replication cycle in which the viral genome becomes incorporated into the bacterial host chromosomes as a prophage and does not kill the host

Hint 12

or uses reverse transcriptase to reverse transcribed DNA from RNA and then incorporated into the host cell

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reverse transcriptase

Back 13

an enzyme encoded by retroviruses that uses RNA as a template for DNA synthesis

Hint 13

gets incorporated into the host genome

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temperate virus

Back 14

a virus in a lysogenic cycle

Hint 14

host cell may show no signs of infection

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provirus

Back 15

viral DNA that inserts into a host genome

Hint 15

prophage if host is a bacterium

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plus-strand RNA

Back 16

viruses with this kind of RNA can be directly translated from RNA

Front 17

retroviruses

Back 17

carry the enzyme reverse transcriptase, which allows DNA to be reverse transcribed from mRNA

Hint 17

DNA is then incorporated into host genome

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minus strand RNA

Back 18

needs to be translated to plus strand RNA before being translated

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viroids

Back 19

small rings of naked RNA without capsids

Hint 19

only infect plants

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prions

Back 20

infectious form of protein capable of reproducing themselves without DNA or RNA

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vaccine

Back 21

injection of of antibodies or injection of non-pathogenic virus with the same capsid or envelope

Hint 21

latter allows body to create its own antibodies

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prokaryotes

Back 22

cell that lacks a membrane enclosed nucleus and membrane enclosed organelles

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archaea

Back 23

one of two prokaryotic domains typically found in salty lakes and boiling hot springs

Hint 23

cell walls are not made from peptidoglycan
have similar

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bacteria

Back 24

prokaryotic domain

Hint 24

includes most known prokaryotes

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fixing CO2

Back 25

reducing it and using the carbon to create organic molecules usually through Calvin Cycle

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autotrophs

Back 26

supply their own food

Hint 26

capable of using CO2 as their sole source of carbon

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heterotrophs

Back 27

get food from other sources

Hint 27

use preformed organic molecules (from dead or living organisms) as their source of carbon

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phototrophs

Back 28

organisms that use light as their energy source

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chemotrophs

Back 29

organisms that use oxidation of organic and inorganic matter as their energy source

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nucleoid

Back 30

DNA, RNA and protein complex in prokaryotes

Hint 30

not enclosed by a membrane

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cocci

Back 31

round bacteria

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bacilli

Back 32

rod shaped bacteria

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spirilla

Back 33

helically shaped bacteria

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prokaryotic ribosomes

Back 34

smaller than eukaryotic ribosomes, but still used to translate proteins

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plasma membrane

Back 35

composed of a phosphate group (polar), two fatty acid chains (non-polar) and a glycerol backbone

Hint 35

phosholipid bilayer surrounding prokaryotic cytosol

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amphipathic

Back 36

having both polar and non-polar regions in the same molecule

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micelle

Back 37

spherical structure that results when the polar ends of a molecule turn towards aqueous solution and non-polar ends turn away from solution

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integral/intrinsic proteins

Back 38

amphipathic proteins that transverse the membrane, from the inside to the outside of the cell

Front 39

peripheral/extrinsic proteins

Back 39

situated entirely on the surface of the membrane

Hint 39

ionically bonded to integral proteins or the polar group of a lipid

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fluid mosaic model

Back 40

asymmetrical layout of proteins

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diffusion

Back 41

process by which molecules move from areas of high concentration to areas of low concentration

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chemical concentration gradient

Back 42

gradual change in concentration of a compound over a distance

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electrical gradient

Back 43

points in the direction that a positively charged molecule will tend to move

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electrochemical gradient

Back 44

variation of both electric potential and chemical concentration across a membrane

Hint 44

combination of chemical and electrical gradients

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semi-permeable membrane

Back 45

a membrane that can slow the diffusion of a compound, but not fully stop it

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size and polarity

Back 46

two aspects of a compound that affect its semi-permeability

Hint 46

molecular weight over 100 - membranes are generally impermeable

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passive diffusion

Back 47

where molecules move through leakage channels

Front 48

transport/carrier proteins

Back 48

assist in the membrane transport of molecules that are too large or too charged to passively diffuse

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facilitated diffusion

Back 49

type of diffusion executed by transport/carrier proteins

Hint 49

diffusion must occur down the electrochemical gradient of all species involved

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selectively permeable

Back 50

what the membrane becomes due to facilitated diffusion

Hint 50

select between molecules of similar size and charge

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active transport

Back 51

movement of a compound AGAINST its electrochemical gradient

Hint 51

requires expenditure of energy, typically in the form of ATP

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bacterial envelope

Back 52

portion of the bacterium that surrounds the protoplast, and has a component, the cell wall, closes to the plasma membrane

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hypertonic

Back 53

aqueous solution of cytosol contains more particles than aqueous solution surrounding cell

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hypotonic

Back 54

aqueous solution of cytosol contains less particles than aqueous solution surrounding cell

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hydrostatic pressure

Back 55

the pressure at a point in a fluid at rest due to the weight of the fluid above it

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osmotic pressure

Back 56

pressure exerted by the flow of water through a semi-permeable membrane separating two solutions with different concentrations of solute

Front 57

peptidoglycan

Back 57

series of disaccharide polymer chains with amino acids that make up bacterial cell walls

Hint 57

more elastic than cellulose

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gram staining

Back 58

staining technique used to prepare bacteria for viewing under the light microscope

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gram positive bacteria

Back 59

thick peptidoglycan cell wall prevents the stain from leaking out and makes the cell look purple

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gram negative bacteria

Back 60

thin peptidoglycan cell walls allow stain to leak out and makes the cell look pink

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bacterial flagella

Back 61

long, hollow, rigid cylinders made from globular protein called flagellin

Hint 61

rotated counterclockwise - propel bacterium in single direction
rotated clockwise - bacterium tumbles

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flagellin

Back 62

globular protein

Front 63

genetic recombination

Back 63

production of offspring that combine traits of the two parents

Hint 63

bacterial forms are conjugation, transformation and transduction

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binary fission

Back 64

each dividing daughter cell receives a copy of the single parental chromosome

Hint 64

way in which prokaryotes reproduce

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conjugation

Back 65

the direct transfer of DNA between two cells that are temporarily joined by the sex pilus

Hint 65

must contain a plasmid that has the gene for the sex pilus

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plasmid

Back 66

small circles of DNA that exist and replicate independently of the bacterial chromosome

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F Plasmid

Back 67

DNA segment that confers the ability to form pili for conjugation and associated functions required for the transfer of DNA from the donor to the recipient

Hint 67

fertility factor; can be a plasmid or integrated into the bacterial chromosome

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R Plasmid

Back 68

a bacterial plasmid carrying genes that confer resistance to certain antibiotics

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transformation

Back 69

a change in genotype and phenotype due to the assimilation of external DNA by a cell

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transduction

Back 70

a DNA transfer process in which phages carry bacterial genes from one host cell to another (harmless)

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vector

Back 71

the virus that mediates transduction

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fungi

Back 72

eukaryotic kingdom that includes organisms that absorb nutrients after decomposing organic material

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saphrophytic

Back 73

living off dead organic matter

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septa

Back 74

cell wall of a fungi

Hint 74

usually perforated to allow cytoplasmic streaming

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chitin

Back 75

polysaccharide that makes up the cell wall of fungi

Hint 75

more resistant to microbial attack than cellulose

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mycelium

Back 76

densely branched network of hyphae in a fungus

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hyphae

Back 77

a filament that collectively makes up the body of a fungus

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spores

Back 78

a meiotically produced haploid cell that divides mitotically, producing new mycelia through asexual reproduction

Front 79

budding/cell fission

Back 79

asexual reproduction in which outgrowths from the parent form and pinch off to live independently or else attached to eventually form colonies