Chapter 7

What are the six essential elements ?

Also called trace elements CHONPS Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur

Mesophiles

Grow in Moderate temperature. they grow within the range of human body temperature 20c-40c . Example of a mesophile will be clostridium

Thermophiles

Heat loving (45-80c) best growth in 50c-60c example of thermophiles is most spores- forming bacteria, best grows in this enviroment

Another way to categorize nutrients is according to their carbon content

Inorganic nutrients organic nutrients

Photoheterotrophs

Use chemical substance (organic) as their main source of carbon and light as their source of energy Example non-sulfur bacteria

Chemoautotrophs

Use chemical substances(inorganic) as source of energy and CO2 as their main source of carbon. Neither sunlight nor organic nutrients, they recycle inorganic nutrients Examples methanogens

Photoautotrophs

Use light as a source of energy and CO2 as their main source of carbon. Photosynthetic organisms ,example algae and plants

Mixed culture

contains different species in the same cultrue medium; contains 2 or more identified and differentiated species of microorganisms Microorganisms in nature exist in mixed culture

Death or decline phase

decline in the viable, live populations untll all cell side

pH

degree of acidity or alkalinity; ranges from 0 to 14

Nitrogen

essential part of amino acids, DNA, RNA, and ATP

Each new fission cycle increases the population by a factor of two

exponetial or lagrithmic growth

Obligate acidophiles

grow at extreme acid pH

Alkalinophiles

grow at extreme alkaline pH

Most microbes exist under

hypotonic and isotonic solution

There are 4 phases in microbial growth which are?

1.)Lag phase 2.)Exponential growth phase 3.) Stationary phase 4.)Death or decline phase

Out of this 95 how many are of biological importance

25 elements

Microaerophiles

Are arobes that requiere very small amount of oxygen Requiere small quantities of oxygen

Aeroteolerant Anaerobes

Areaenerobes that can tolerate small amounts of oxygen Note: Aerotolerant microbes are Anaerobic

There are two classifications based on the type of compounds the organism use as their carbon source

Autotrophs Heterotrophs

The growth of Bacterial Cultures

Bacterial growth refers to an increase in protoplasm (size), as well as an increase in the number of cells

Bacteria reprduce by?

Binary fission

Facultative Anaerobes

Can grow with or without oxygen They do not require O2 for growth, but they may use it for metabolism and chemical reactions Under anerobic conditions, they are fermentation for energy

Strict obligate Aerobes

Can only grow in O2 these are strict they have to grow in oxygen without oxygen they cant grow

Carbon Dioxide requierement

Capnophile--- grows best at higher CO2 tensions that normally present in the atmosphere All microbes requiere some carbon dioxide in their metabolism.

2Chemical requirements of microbial growth are

Carbon forms a backbone of carbohydrates, lipids and poteins Compose half of the dry weight of a bacterial cell 2 types of organisms based on the type of compounds they use as carbon sources; Autotrophs (self feeders) Heterotrophs (other feeders)

What is osmotolerant

Do not require high concentration of solute but can tolerate it when it occurs.

Trace elements

Mineral elements needed in extremely small amounts such as zinc, copper,colbat, nickel, iron, silicon and Iodine Iodine has to be at equilibrium you need Iodine in your food so you wont have Goiter because Goiter causes swelling of the thyroid gland

The 3 cardinal temperatures where micoorganisms grow are?

Minimum Temperature Maximum Temperature Optimum Temperature

There are three primary groups of microorganisms based on their optimum temperature ranges:

Psychophiles Mesophiles Thermophiles

What are the two main types of culture ?

Pure culture Mixed culture

There are three types of simbiotic relationships which are?

Mutualism Commensalism Parasitism

What does Nf=(Ni)2n stand for

Nf= is the total number of cells in the population Ni= is the starting number of cells Exponent n denotes the number of generations 2n = number of cells in that generation

The Equation for calculating population size over time is?

Nf=(Ni)2n

Barophiles

Organisms that can survive under extreme pressure and will rupture if exposed to normal atmospheric pressure

Osmotic pressure

Osmotic pressure refers to the force with which water moves through the cytoplasmic membrane from the solution containing a low concentration of dissolves(solutes) to one containing a high solute concentration

Oxygen requirements

Phisiological groups are based on how microbes handle O2

Combination of 2 classifications

Photoautotrophs Photoheterotrophs Chemoautotrophs Chemoheterotrophs

What are the two classifications based on how the organism obtain energy

Phototrophs Chemotrophs

There are two requierements for microbial growth

Physical requirements chemical requirements

Inoculation and Isolation procedures

Streak plate method--- streaking the material across the medium surface with a n inoculating loop

1Physical requirements for microbial growth are?

Temperature Microbes require temperature to grow. Microorganisms grow over a broad range of temperatures . Growth rate( number of cell divisions per hour) doubles for every temperature increase of 10c( under favorable conditions)

Colony

The growth of microorganisms on a a solid culture media

Maximum Temperature

The highest temperature, allowing the organisms growth and metabolism, above this level the activities will stop and the cell will eventually die. Above this temp growth will stop if it continues to rise beyond that point, the enzymes and nucleic acid will become permanently incative and the cell will die.Above this temperature it will not grow

Inoculation

The introduction of a sample of microorganisms into a medium or media using tools such as loops,needles, swabs.

Chemotrophs

Use chemical compounds (organic or inorganic)

Chemoheterotrophs

Use chemical substance (organic) as sources of energy and carbon Majority of heterotrophs (saprobes -dead matter---parasite---living host)

Minimum Temperature

The lowest temperature for the organisms growth and metabolism; below this level, the activities are inhibited. They dont grow below this level

Optimum pH

The middle of the pH range over which growth occurs(6--8)----(6.5-7.5) microorganisms based on their optimum pH pH at which an enzymatic or any other reaction or process is most effective under a given set of conditions

What is the difference between inorganic and organic nutrients

The presence or absence of carbon is what differentiates organic nutrients from inorganic nutrients. Carbohydrates, lipids, proteins and vitamins have carbon in their structure, making them organic. Water and minerals do not, so they are inorganic.

Generation (doubling )Time

The time needed for a complete fission cycle --- the time interval requiered for each microbe to divide, or for the population in a culture to double.

How nany are essential

There are 6 that are essential

Generation of doubling time

Time requiered for a complete fission cycle

Inoculation should be performed under controlled conditions, using Sterile techniques( sterile media and tools) why?

To prevent possible contamination

Phosphurus

a mojor component of nucleic acids (DNA and RNA) also needed for ATP synthesis

Optimum temperature

a range of temperatures at which a species of microorganisms grows most rapidly

Culture Media

a substance used to provide the nutrients for the growth and multiplication of microorganisms

Organic nutrients

contain carbon and hydrogen atoms and are usually the products of living things methane (CH4), carbohydrates, lipids, proteins, and nucleic acids

pH under 7 means that its

acidic

pH over7 means that its

alkaline

Pure culture

all the cells in the population are identical; since they come for mthe same parent cell. Grows only single known species of microorganisms

Micro-nutrients

also called Trace elements they are required in small amounts. word micro means small, Example, manganese, zinc, nickel

Lag phase

also called the padromal phase initial period; few or no cells No growth of increase in cell number

Essential nutrients

are the type of nutrients that must be provided to an organism each organism should have essential nutrients they are important

Inorganic nutrients

atom or molecule that contains a combination of atoms other than carbon and hydrogen Examples metals and their salts(magnesium sulfate,ferric nitrate, sodium phosphate),gases(oxygen, carbon dioxide) and water.

Major component of organic compounds are

carbohydrates,lipids,and proteins

The viable count technique occurs in a ?

closed system

Phychophiles

cold loving. They grow between 15C -20c . they cannot grow above 20c. Example of phychophiles will be Pseudomonas.

commensalism

commensal member benefits, other member not harmed.

Successive divisions by the daughter cells

increase in population

other minute- trace elemets are?

iron,silicon,magnesium,maganese,vitamins, inorganic salts like sodium, chloride, calcium etc.

Generation Time

is also the rate of population growth

What is binary Fisssion

is when one parent cell becomes two cells as a resulf to division-- the parent cell enalarges, duplicates its chromososmes, and forms a septum dividing the cell into 2 daughters, the septum is called the clevage furrow.

What are the two types of essential nutrients?

macro-nutrients micro-nutrients

pH

majority of microorganisms grow at a pH between 6 and 8

Strict obligate Anaerobes

may be poisoned by O2 they cannot grow in the presence of oxygen. They lack the enzyme (superoxide dismutase (SOD) that breaks down oxygen and its products

Microorganisms can be classified based on their

metabolism, and their sources of essential nutrient (CHONPS)

Sulfur

needed for the biosynthesis of some amino acids Ex methionine

pH=7 (neutral)

neither acidity of alkalinity; as in water

Stationary phase

no new growth; reduction of live cells

closed system

no new nutrients are added to the system, and no metabolic wastes are removed

Mutualism

obligatory, dependent; bothe member benefit

What is symbiotic relationships

organisms live in in close nutritional realtionships; required by one or bothe members to survive

Extreme halophiles

organisms that require high salt concentration for growth; may also be called abligate halophiles

Nutrition

process by which chemical substances (nutrients) are obtain from the enviroment and used for cellular activities

Exponential growth phase

rapid, balanced growth; mostly live cells; move vulnerable to the antimicrobial agents starts to divide exponentially

Aerobes

requiere oxygen for growth, and can grow in a standard air atmosphere of 21% oxygen

Macro-nutrients

required in large quantaties; by living organisms play a principal roles in cell structure and metabolism Examples proteins, carbohydrates and lipids these are required for the human body wich are calories

Facultative halophiles

resistant to salt, they do not require hight salt concentration , but are able to grow at salt concentration up to 2% ; some can even tolerate 15%

Ecological realtionships among microbes

symbiotic relationships Nonsymbiotic relationships (most important)

Balanced growth

the exponential growth of a microbial culture

Growth pattern

the growth pattern grow exponentially;geometricly(increase in geometric progression

There is a total of how many occuring elements

there are about 95

Autotrophs

use CO2 (inorganic) as their major source of carbon CO2 is the only inorganic molecule that contain carbon

Phototrophs

use light(radient energy) to obtain its energy

Heterotrophs

use organic compounds as their major source of carbon They obtain organic compounds by absorbing them from the enviroment, or by ingesting autotrophs or other heterotrophs

The common method

viable count technique which is counting the total number of live cell over a given period of time