Micro 233

All the bacteria cells that result from the replication of a single original bacterial organism are said to be a

The scientist that contributed most to the development of pure culture techniques was

The solidifying agent used most successfully in bacterial nutrient media is

Prokaryotic cells divide by a process known as

In nature, bacteria

Biofilms

The simplest technique for isolating bacteria in growth media is referred to as the

Bacteria may be stored

In the growth curve of a bacteria population, the bacteria are rapidly increasing in number in the

During which phase of growth are bacteria most susceptible to antibiotics?

When doing experiments with bacteria

During which phase of the bacteria growth curve does the total number of viable cells decline?

The lag phase of the bacterial growth curved is marked by

Late log phase of the bacterial growth curve

During which phase of the bacterial growth curve does a bacterial population become much more resistant to harmful conditions

A urine sample with more than 100,000 organisms, is considered indicative of infection. A urine sample containing 5,000 bacteria, with a generation time of 30 min sits for 3 hrs before finally being assayed. How many bacteria will then be presented within the sample?

A pure culture in exponential growth phase has a bacterial concentration of 6.4 * 10^8 cell/ml if the bacterium has a generation time of 1h, How long ago was the cell concentration 8.0*10^7 cells/ml?

In a rapidly multiplying bacterial population, cell numbers increase

The speed of enzymatic reactions approximately doubles for each

Generally the proteins of thermophiles

A hot tub (approx. 104 deg F or 40 deg C) would most likely contain

The optimal temp. for most human pathogens might be expected to range from

Bacteria on fish caught in the Artic Ocean would

Mycobacterium leprae is typically found infecting the ears, toes and fingers of its host due to its

Organisms that require gaseous oxygen for metabolism are referred to as

Which of the following is/are obligate aerobes?

Organisms that are indifferent to the presence of oxygen and do not use it are

The enzymes that deal with toxic oxygen - containing molecules is/are

Shake tubes are used to determine the

The optimum pH for growth of most species of bacteria is

High concentrations of salt and sugar in foods

Carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur may be considered

Trace elements

Small organic molecules that must be provided to bacteria in order for them to grow are called

The prefix photo-indicates that an organism will make use of ____ for energy purposes.

Organisms that use organic molecules as their source of carbon are called

Organisms may derive energy from

Organism that use CO2 as their source of carbon are called

Chemoheterotrophs

An organism called Bacillus fastidiosus

Peptone

Medically important bacteria are often

Products which limit pH changes are often incorporated into media and are referred to as

A medium that inhibits the growth of organisms other than the one being sought is termed a(n)

MacConkey agar is

Candle jars are usually used to

In the cultivation of microaerophilic and anaerobic bacteria

Agar

Agar replaced gelatin as the gelling (solidifying) agent for media because

It is assumed that every colony observed on a streak plate arose from a single bacterium

In microbiology, growth usually refers to an increase in size of the bacterium

There are 5 stages of growth in an open system of culture.

Secondary metabolites may be antibiotics

A single bacterial cell may multiply to form a visible colony

Prokaryotes are the only organisms able to use atmospheric nitrogen as a nitrogen source

Freezing is an effective means of destroying bacteria

One would expect most strict anaerobic organisms to have superoxide dismutase.

Differential media only allows certain bacteria to grow

A microbe is discovered growing hear a deep sea thermal vent when researchers bring a sample up to the surface and try to grow it in a lab at room temp. in a normal incubator, they are unsuccessful. Why?

You are a microbiologist working for a pharmaceutical company and discover a new secreted metabolite that can serve as a medication. Your company asks you to oversee the production of the metabolite which of the following is something that is NOT important to consider if you need to grow 5,000 liter cultures of bacteria for the purpose of harvesting the metabolite they secrete.

You are working in a clinical laboratory in a hospital setting. You're handed a throat swab from a patient. You are told specifically that the physician is only interested in what Gram positive cells are present what might you do first to go about working towards this goal? Identification isnt the main goal here just a first step to work towards determining what Gram positive cells might be there...

A physician send a stool sample to your lab, and wants to know if there are lactose formenting microbes in the sample. How might you determine if these microbes are present or not from this mixed-microbe specimen?

Your are in charge of water quality for your city's water treatment plant of the methods at your disposal, which will be the most efficient and cheapest method of determining the number of viable bacteria in the water coming out of your plant?

You take absorbance readings on a spectrophotometer across a lehr culture of E. coli cells growing in tryptic soy broth (TSB) Your absorbance readings clearly indicate a lag phase, a log phase, and a stationary phase. You come back and take readings at 8,10,12,14+16hrs. but the absorbance number remains the same. Shouldnt it start coming down as the closed batch culture enters death phase? Whats the most likely thing that is happening?