Lesson 6: Microorganisms Flashcards
(31 cards)
What are viruses?
Minute organic forms which seem to be intermediate between living cells and organic compounds
How do viruses differ in size compared to bacteria?
Viruses are smaller than bacteria
What is the maximum magnification needed to see viruses through an electron microscope?
1,000,000x
List some diseases caused by viruses
- Poliomyelitis
- Smallpox
- Measles
- Mumps
- Encephalitis
- Influenza
- Common cold
How do viruses reproduce?
They invade our body and use our cells to duplicate themselves
What is a common indication of viruses in food supply?
Contamination through human feces
What are the two most common types of viruses in the food industry?
- Hepatitis A
- Noroviruses
True or False: Noroviruses are highly contagious.
True
What can Hepatitis A virus affect?
The liver
What are parasites?
Organisms that live in or on other organisms without benefiting the host
Name two common parasites in the food industry.
- Trichinella spiralis
- Anisakid worm
Fill in the blank: Anisakiasis is associated with _______.
[raw marinated fish such as sushi, sashimi, ceviche]
What is one method to control Anisakiasis?
Freeze fish at minus 31 °F for 15 hours
What are yeasts?
One-celled organisms which are larger than bacteria
What do yeasts require for proper growth?
- Food
- Moisture
- Warmth
- Air
How do yeasts reproduce?
By budding
What do yeasts produce when they act on sugar?
- Alcohol
- Carbon dioxide
What is the maximum alcohol concentration yeasts can tolerate?
18%
What do wild yeasts cause?
Food spoilage and decomposition of starch and sugar
True or False: Yeasts are generally considered pathogenic.
False
What are molds?
Multicellular microscopic plants which become visible to the naked eye when growing in sufficient quantity
What colors can mold colonies have?
- White
- Black
- Green
What diseases can some molds cause?
- Athletes’ foot
- Ringworm
- Other skin diseases
What is the structure of mold composed of?
- Mycelium
- Hypha
- Sporangium
