Ch. 7 Microbial Nutrition, Ecology, And Growth

Front 1

adaptation

Back 1

gradual adjustment of anatomy and physiology to improve an organism's survival in a given environment

Front 2

nutrition

Back 2

process by which nutrients are acquired from the environment and used in cellular activities such as metabolism and growth

Front 3

essential nutrient

Back 3

any substance that must be provided to an organism

Front 4

macronutrients

Back 4

essential nutrients required in relatively large quantities and play principal roles in cell structure and metabolism

ex: compounds containing C, H, O

Front 5

micronutrients (trace elements)

Back 5

essential nutrients present in much smaller amounts and are involved in enzyme function and maintenance of protein structure

ex: manganese, zinc, nickel

Front 6

organic

Back 6

has C and H

Front 7

inorganic

Back 7

composed of elements other than C and H

Front 8

heterotroph

Back 8

organism that must obtain its carbon in an organic form

Front 9

autotroph

Back 9

organism that uses inorganic CO2 as its carbon source

Front 10

growth factor

Back 10

an organic compound that cannot be synthesized by an organism and must be provided as a nutrient

ex: aas, nitrogenous bases

Front 11

phototroph

Back 11

microbes that photosynthesize

Front 12

chemotroph

Back 12

microbes that gain energy from chemical compounds

Front 13

obligate

Back 13

being restricted to a narrow niche or habitat

Front 14

facultative

Back 14

not being so restricted but adapting to a wider range of environmental conditions

Front 15

chemoautotroph

Back 15

survive totally on inorganic substances as minerals

Front 16

methanogens

Back 16

chemoautotrophs that produce methane gas

Front 17

chemoheterotroph

Back 17

derive carbon and energy from organic compounds

Front 18

saprobes

Back 18

free-living microbes that feed primarily on organic detritus from dead organisms

Front 19

parasites

Back 19

derive nutrients from the cells and tissues of a host

Front 20

obligate parasites

Back 20

unable to grow outside of a living host

ex: leprosy, syphilis

Front 21

diffusion

Back 21

net movement of molecules down their concentration gradient by random thermal motion

Front 22

passive transport

Back 22

transport that does not require extra energy expenditure

Front 23

osmosis

Back 23

diffusion of water through a selectively permeable membrane

Front 24

isotonic

Back 24

environment is equal in solute concentration to the cell's internal environment

Front 25

hypotonic

Back 25

solute concentration of the external environment is lower than that of the cell's internal environment

Front 26

plasmolysis

Back 26

shrinkage of the protoplast away from the wall in cells with a cell wall due to water loss

Front 27

hypertonic

Back 27

exposed to a solution with higher solute concentration than its cytoplasm

Front 28

turgid

Back 28

being swollen or congested due to pressure

Front 29

facilitated diffusion

Back 29

passive transport utilizing a carrier protein in the membrane that will bind a specific substance. binding changes the conformation of the carrier proteins in a way that facilitates movement of the substance across the membrane

Front 30

specificity

Back 30

ability to bind and transport only a single specific substance

Front 31

active transport

Back 31

transport of nutrients against the diffusion gradient (or faster with the gradient), presence of specific membrane proteins, and the expenditure of additional energy

Front 32

carrier-mediated active transport

Back 32

uses specific membrane proteins that bind ATP and the molecules to be transported. ATP release drives the movement of the molecule through the protein carrier

Front 33

group translocation

Back 33

active transport that couples the transport of a nutrient with its conversion to a substance that is immediately useful inside the cell

Front 34

endocytosis

Back 34

transport by enclosing the substance in a membrane

Front 35

phagocytosis

Back 35

ingestion of whole cells or large solid matter

Front 36

pinocytosis

Back 36

mechanism for the entrance of liquids into the cell

Front 37

cardinal temperatures

Back 37

range of temperatures for microbial growth

Front 38

minimum temperature

Back 38

lowest temperature that permits a microbe's continued growth and metabolism; activities are inhibited below this temp

Front 39

maximum temperature

Back 39

highest temperature at which growth and metabolism can proceed

Front 40

optimum temperature

Back 40

a small range, intermediate between the min and max which promotes the fastest rate of growth and metabolism

Front 41

psychrophile

Back 41

optimum temp < 15C

capable of growth at 0C

cannot grow > 20C

Front 42

mesophile

Back 42

grow at intermediate temperatures

optimum growth temps = 20-40C

Front 43

thermophile

Back 43

grows optimally at > 45C

will grow 45-80C

Front 44

aerobe

Back 44

can use gaseous oxygen in its metabolism and possesses enzymes to process toxic oxygen products

Front 45

obligate aerobe

Back 45

organism that cannot grow without oxygen

ex: fungi, protozoa

Front 46

facultative anaerobe

Back 46

aerobe that does not require oxygen for metabolism, and is capable of growth in its absence

Front 47

microaerophile

Back 47

does not grow at normal atmospheric concentrations of oxygen, but requires a small amount of it in metabolism

Front 48

anaerobe

Back 48

lacks metabolic enzyme systems for using oxygen gas in respiration

Front 49

aerotolerant aerobe

Back 49

do not utilize oxygen gas, but can survive and grow in its presence

Front 50

capnophiles

Back 50

grow best at higher CO2 than normally present in the atmosphere

Front 51

neutrophiles

Back 51

living around pH7

Front 52

acidophiles

Back 52

lives at low pH

Front 53

alkalinophiles

Back 53

lives up to pH 10

Front 54

halophiles

Back 54

osmophile requiring high concentrations of salt

Front 55

osmotolerant

Back 55

microbes that adapt to wide concentrations in solutes

Front 56

barophiles

Back 56

exist under pressures greater than the atmosphere

Front 57

symbiosis

Back 57

two organisms live together in a close partnership

Front 58

mutualism

Back 58

mutually beneficial relationship

Front 59

parasitism

Back 59

host organism provides parasite with nutrients and a habitat

Front 60

synergism

Back 60

cooperation

Front 61

antagonism

Back 61

competition that occurs when the actions of one organism affect the success and survival of others

Front 62

antibiosis

Back 62

production of inhibitory compounds

Front 63

quorum sensing

Back 63

process of biofilm formation

Front 64

inducer molecules

Back 64

molecules that induce an effect

Front 65

quorum

Back 65

critical number of cells

Front 66

binary fission

Back 66

one cell becomes two

Front 67

transferse fission

Back 67

division plane forming across the width of the cell

Front 68

lag phase

Back 68

an early flat period

Front 69

exponential growth (logarithmic) phase

Back 69

period where the curve increases

Front 70

stationary growth phase

Back 70

cells stop growing or grow slowly

Front 71

death phase

Back 71

cells die at an exponential rate and most are unable to multiply

Front 72

turbid

Back 72

cloudy