ch.6: MiCROBiAL GROWTH

\___ - tolerates but can't use oxygen ...sadness

aerotolerant anaerobes

if they don't have O2 it is \_____

peroxidase

what is an "orderly and permanent increase in the pass of protoplasm of an organism or population"called?

growth

what a "proportionate increase in all constituents (component)" called?

orderly

microbial growth \= ?

increase in NUMBER of cells, not the size

simply define complex medium

unknown (don't known) amount

cells may grow \______

without reproducing

cell may \______

reproduce without growth

name the physical requirements for growth:

temperature, pH, and Osmotic pressure

name the chemical requirements for growth:

carbon, nitrogen/sulfur/phosphorus, trace elements, Oxygen, and organic growth factors

\_____ is where growth occurs

minimum temp

\____ is where a species grows best

optimum temp

\____ is where growth is possible

max temp

name the temperatures regarding environmental factors:

psychrophiles, mesophiles, thermophiles

\____ \= "cold loving"

psychrophiles

\____ \= "middle" loving

mesophiles

\____ \= "heat-loving"

thermophiles

what temps do psychrophiles grow at?

0C and 20C/30C

what is the optimum temp for psychrophiles?

15C

what the minimum temp for psychrophiles?

0C

what the max temp for psychrohiles?

20C

what are the temps mesophiles grow at?

20C to 45C

what minimum temp for mesophiles?

20C

what max temp for mesophiles?

45C

what the minimum temp for thermophiles?

50C

what the maximum temp for thermophiles?

65C

which -phile causes food spoilage?

psychrophiles

what is the optimum temp for mesophiles?

25C to 37C

which -phile is found in hot springs and organic compost?

thermophiles

\______ grow at 50C to 65C

thermophiles

what temps do thermophiles grow at?

50C to 65C

what phile has the lowest rate of growth?

psychrophiles

what phile has the highest rate of growth?

thermophiles

\_____ - Grow between 0°C and 20-30°C, Cause food spoilage

psychographs

What temps are the major danger zones? (celcius)

15 - 53

What temps are the major danger zones? (Fahrenheit)

60-125

what temps prevent significant growth?

-30C to 0C (below freezing)

what is consider refrigerator temp?

0C to 5C

what can 0C to 5C possibly cause?

slow growth of spoilage bacteria, very few pathogens

what does 15C to 52C indicate?

rapid growth of bacteria. some may produce toxins.

what does 52C to 62C indicate?

very slow bacterial growth

what does 62C-130C (and up) indicate?

most microbes are destroyed...although lower temps take more time

what pHs do most bacteria grow between?

6.5 and 7.5

what pH do most molds and yeasts grow between?

5 and 6

what is the minimum pH of growth for bacteria?

6.5

what is the maximum pH of growth for bacteria?

7.5

what kind of environments do acidophiles grow in?

acidic

what is minimum pH of mold and yeast (fungus) growth?

5

what is max pH of mold and yeast (fungus) growth?

6

\_____: acid loving! have optimums between pH 0 - 5.5

acidophiles

\____: basic loving! have optimums between pH 8.5 - 11.5

basophiles

what is "acid loving" ?

acidophiles

what is "basic loving"?

basophiles

what is the pH range of acidophiles?

0-5.5

what is the pH range of basophiles?

8.5 to 11.5

what can organisms change due to their own waste products (generally acidic)?

culture media

organisms can change the culture media due to their own \_________, may be toxic due to pH change

waste products (generally acidic)

what are the Osmotic environmental factors?

isotonic, hypotonic, hypertonic environments, extreme or obligate halophiles, and facultative halophiles

\_______ increase salt or sugar, which cause plasmolysis

hypertonic environments

\_____: loss of h2o from a cell in a hypertonic environment

plasmolysis

What requires high osmotic pressure?

extreme or obligate halophiles

What tolerates high osmotic pressure?

facultative halophiles

\_____ grows in high salt conditions! - obligate halophile requires salt ya know

halophiles

\_____: water moves out out cell, cell shrinks hence plasmolysis

hypertonic

\___: h2o will move into cell and cell rounds up and cell can burst, like starbursts!

hypotonic

\______: no net movement!! osmotic pressure is equal across cell's membrane

isotonic solution

what percentage are cells made up of water?

80%-90%

simply define obligate halophiles

must be in high salt environments. No way out! you gotta do it!

simply define facultative halophiles

it is flexible. If situation arises, where we encounter high osmotic environment, the cell can tolerate and be okay!

What is the most important chemical requirements for all life?

carbon

all living things are based on ...?

Carbon

carbon is "\_______"

the backbone of life

what do chemoheterotrophs use as energy?

organic molecules

How do autotrophs obtain energy?

photosynthesis

how do autotrophs use carbon?

CO2

\___ - availability of macronutrients, trace elements, and growth factors

nutrients

\____ - inorganic elements required in small amounts and usually as enzyme cofactors

trace elements

what is the energy source for carbon?

structural organic molecules

location of nitrogen?

amino acids/proteins

In \________, most bacteria decompose proteins

nitrogen and sulfur

what is nitrogen's "bacteria use"?

NH4+ or NO3-

a few bacteria use \_____ in nitrogen fixation

N2

what does bacteria use in nitrogen fixation?

N2

location of sulfur?

amino acids, thiamine, biotin

In sulfur, some bacteria use \____?

SO42- or H2S

In \_______, some bacteria use SO42- or H2S

sulfur

what does phosphorus play important role in?

DNA, RNA, ATP, and membranes

what is the source of phosphorus?

PO43-

What can be limiting factors in growth, Nitrogen fixation very important?

Nitrogen, sulfur, phosphorus

what are organic growth factors?

vitamins, amino acids, purines, pyrimidines

What requires oxygen for growth?

aerobes

What can grow with or without oxygen?

facultative anaerobes

what cannot tolerate molecular oxygen?

anaerobes

what requires oxygen but can only grow at low oxygen tension?

microaerophiles

what must have superoxide dismutase and catalase and peroxidase?

aerobes, facultative anaerobes, and anaerobes

name examples of byproducts:

superoxide radical -superoxide dismutase)! hydrogen peroxide - catalase, peroxidase

what are the effects of oxygen?

organisms can produce more energy when growing in oxygen, but toxic byproducts of oxygen can be fatal to cells

organisms can produce more energy when growing in oxygen, but \________ of oxygen can be fatal to cells

toxic byproducts

define obligate aerobes

requires oxygen

Define facultative anaerobes

grow via fermentation or anaerobic respiration when oxygen is unavailable