Microbiology Lab Test 3

If you had a colony forming unit that was 100 colonies/0.1ml, how many colonies would you have in 1ml?

1,000 (100/0.1 = 1,000)

When testing for food poisoning a plate count above ______________ would be considered poisoned.

250 (25-250 is normal)

What type of immunity has a memory function?

Adaptive immunity

Which type of indicator introduces a decontaminated sample to a new media and sees if the microorganisms can grow again on the media when put into a perfect environment?

Biological

B cells mature in the ... and when activated produce ...

Bone Marrow, Antibodies

Heat treatment in food's purpose?

Both ensures the safety of the food & preserves food quality

All of these are parts of the immune system EXCEPT?

Brain

High level disinfection kills everything but?

ENDOSPORES

Bacterial growth doesn't start until they have been on the media for at least 2 hours.

FALSE

Every microorganism can be killed at the same temperature for the same amount of time.

FALSE

Selective toxicity means that the pathogen is toxic to the drug.

FALSE

The higher the microbial load, the less the item needs to be decontaminated.

FALSE

Wet heat takes longer to achieve sterilization that dry heat.

FALSE

When you are trying to calculate generation time, you only check the population once.

FALSE

What is a difference between the two type of Microbial Foodborne Illnesses?

Food intoxication - it occurs when the pathogenic microorganism secretes a toxin in the food product. Food infection - it occurs when the microorganisms multiply in food until it reaches the minimum infective dose (MID).

Which type of pasteurization is used more commercially today?

High-temperature-short-time (HTST)

Which antibody would you expect to see more of a couple of weeks after the initial infection?

IgG

Which antibody would you expect to see more of in the early stages of an infection?

IgM

Choose all that apply: Differences between sterilization and pasteurization are

Intensity of heat treatment Unlike sterilization, the aim of pasteurization is not to eliminate all microorganisms in the food Method of packaging

Why is food sterilization not done very often?

It ruins the taste of the food.

With a zone of inhibition, an antimicrobial that works against the microorganism will have a?

LARGER zone of inhibition

Choose all that apply: What organisms can be killed by pasteurization?

Molds Mycobacterium tuberculosis Yeasts

Neutrophil:

Most abundant phagocytes in your bloodstream normally

Choose all that apply: Which are characteristics of innate immunity?

Not specific, generalized Born with it

Which cells are responsible for making antibodies?

Plasma cells

Dendritic cells:

Present pathogens to the T cells

T Helper Cells:

Responsible for changing B cells into plasma cells most of the time

Mast Cells:

Responsible for working in the inflammation process

Eosinophil:

Responsilbe for allergic reactions and kills parasites that are too large to be phagocytosed

Antibiotics are used to treat bacteria only.

TRUE

Antibodies have a Y-Shape. Antigens attach to the top of the antibody.

TRUE

Antisepsis lowers the microbial load on your skin.

TRUE

Bacteria can transfer antibiotic resistance across species.

TRUE

Fruits and beans are good foods to can.

TRUE

T cells mature in the .... and they help to activate ...

Thymus, B cells and kill bad cells

How does pH affect heat treatment?

Time and level of treatment can be affected

How are scientists working to try and combat organisms that are resistant to certain antibiotics?

Trying to develop new drugs or drug cocktails.

Choose all that apply. Critical items

contact normally sterile tissue (like blood) Non Heat sensitive items should be sterilized with steam. Forceps are critical items

Capsules:

cover the microorganisms and keep them from being noticed or phagocytosed

Choose all that apply. SemiCritical items

endopscopes would be semicritical must be cleaned with high level disinfectants must be thoroughly cleaned before it is sent through other decontamination processes

Stationary:

growth slows down because of lack of resources. Cells are aslo dying

Antigenic variation:

making small changes to their surface structures so memory cells can't recognize them

Lag:

no measurable increase in number of bacteria because they are adapting to their new environment

How many E. coli could you expect to have in a 10 hour period?

one billion

Exponential/log:

rapid increase in the bacterial number

Basophil:

responsible for working in the inflammation process

Enzymes:

secreted by microorganisms and can destroy immune cells

Death:

shortages of resources leads to an increase of dead cells than living cells

Microbial load is?

the number of infectious pathogens on an object or in an organism

Choose the best answer. In a hospital, cleaning techniques are put into place

to control the spread of infection.

What is so great about sterilization?

Sterilization gets rid of the entire microbial load meaning there are no microorganisms and no endospores present.

Low level disinfection only kills?

SOME BACTERIA

Choose all that apply: Which are characteristics of adaptive immunity?

Specific to specific antigens Acquired over a lifetime

Which phase is best for making antibotics?

Stationary phase