Microbiology HCC Dr. Harold Kay Njemanze Test 1 Review

1. Characteristics of Viruses

1. They are obligate, intracellular parasites of bacteria, protazoa,fungi,algae,plants,and animal

2. Acellular. Are not cell like.

3. Ultramicroscopic

4. Do not have the characteristics of life

5. Inactive when outside the host cell.

6. Basic structure consist of protein shell (capsid) which surrounds a nucleic acid (core)

7. Nucleic acid can be either DNA or RNA but never both

8. Nucleic Acid can be dsDNA, ssDNA, dsRNA or ssRNA

9. Viruses are specific to host cells

10. Multipies by taking control of host cell's metabolic activities

2. What is lysogenic phase of the viral multiplication cycle?

Lysogenic Cycle (temperate phages)

These viruses do not cause lysis and death of the host cell

Stages:

1. Attachment (adsorption)

2. Entry ( penetration)

3. Uncoat (no uncoat in bacteriophage of animal host cells)

4. Integration

This forms a PROPHAGE or a PROVIRUS

3. What is a prophage?

A viral infection that does not cause lysis or death of the host cell instead it remains dormant.

4. What are parts of a virus?

1. Nucleic acid/Genome (DNA orRNA **Never both)

2. Protein/capsid (protein coat that encloses and protects the nucleic acid)

5. What are nucleocapsids?

The combination of the viral particle's nucleic acid and capsid.

6. What are capsomers?

Identical sub-unit structures made of protein that form the capsid.

7. How are viral infections treated?

Treat the symptoms and reduce rate of multiplication.

8. What are infectious naked strands of RNA called?

Viriod- short pieces of naked rna (no protein coat)

9. What are infectious protein particles called?

Prions- miisfolded and malformed proteins molecule. They contain no nucleic acid

10. What are viral growths in bird embryos that can cause discrete, opaque spots in the embryonic membranes called?

Pocks

11. What are visable, clear, well- defined patches in a monolayer of virus- infected cells in a culture are called?

Plaques

12. What is the sequence of events in viral multiplication?

Viral multiplication has to different cycles Lytic and Lysogenic.

Lytic cyle - results in death of host cell

1. Adsorption - Binding of virus to specific molecule on a host cell.

2. Penetration - Genome enters the cell.

3. Uncoating - The viral nucleic acid is released from the capsid.

4. Integration

5. BioSynthesis - Viral components (proteins and genome) are produced

5a- synthesis of viral proteins

5b- synthesis of viral genome

6. Assembly - new viral particles are assembled.

7. Release - Assembled viruses are released by exocytosis or cell lysis.

Assembly and release of Virions

Lysogenic Cycle

Viral multiplication does not cause lysis and death of the host cell.

1. Attachment

2. Entry - penetration

3. Uncoat

4. Integration

This forms a PROPHAGE or a PROVIRUS

13. Subunits of capsids are called?

Capsomeres

14. How is a virus family name written?

Viruses are classified by 3 Order, 63 Families, 263 genera of viruses

.

They are classified by structure, chemical composition, and genetic makeup.

Order ends in virales

The three orders --> (Caudovirales, Mononegavirales, Nidovirales)

Family name ends in virdae.

Genus name ends in virus

.

Speices - not specified on boon

15. What does the core of every virus particle contain?

Nucleic acid molecules (DNA or RNA )

16. What is the decolorizer in the gram stain?

Ethyl Alcohol

17. What is the primary dye in the acid fast stain?

Carbol Fuschin

18. What is the cell structure that is an important agent in modern genetic engineering techniques?

Plasmid

19. What is the mordant in the Gram stain?

Gram's iodine, which increases contrast

20. Bacteria with a bunches of flagella emerging from the same site are said to be what ?

Lophotichous-->cluster of flagella at one pole

lopho = crested

21. What is the sequence for a Gram stain?

- Crystal Violet for 60 sec

- Wash

- Iodine for 60 sec

- Wash

- 95 % Ethanol for 30 sec

-Wash

- Safranin

22. What are endospores?

They resistance extreme conditions. These are dormant forms of prokaryotic microorganisms. They for spores and cyst that can survive unfavorable conditions, excessive drying or heat. They are metabolically inactive --> not growing. Under favorable conditions, they start to grow and germinate. They are then known as VEGATATIVE PATHOGENS ( which are easy to kill)

23. Know Taxomy heirarchy

Dear King Phillip Came Over For Good Soup

Domain

Kingdom

Phyllum

Class

Order

Family

Genus

Species

24. What are the six I's of studying microbes?

1.Inoculation - introduction of a sample into a container of media to produce a culture.

2.Incubation - under conditions that allow growth.

3.Isolation - separating one species from another

4.Inspection

5.Information gathering

6.Identification

25. Know the different types of culture?

Three main types of culture

1. Pure culture- grows only single known species of microorganisms. All the cells in the population are identical; since they come from the same parent cell

2. Mixed culture- hold two or more identified species or microorganisms. Contains different species in the same culture medium; contains two or more identified and differentiated species of microorganisms

3. Contaminated Culture- Once pure or mixed culture that now has unwanted microbes. Culture medium that contains unwanted microbes.

26. Know the different types of media?

Media provides nutrients to microbes and are classifies as:

1. Physical State - Liquid, semisolid, and solid.

2. Chemical composition - synthetic (artificial) non-synthetic (natural)

3. Functional type - general purpose, enriched, selective, differential, anaerobic, transport, assay, enumeration.

27. What is chemotaxis?

Bacteria movement in response to chemicals in the environment

Postive Chemotaxis--> movement toward chemicals ( increasing levels of attractants)

Negative Chemotaxis --> movement away from chemicals ( increasing levels of inhibitory substances)

28. What is the cell wall content of gram negative and gram positive bacteria?

Gram negative - contains LPS (lipopolysaccharide) think layer of petidoglycan, and lipoproteins.

More complex

Has LPS

Thinner layer of peptidoglycan

Contains an outer lipid memrane (lipoproteins)

Gram stain reaction: loses the primary stain and takes up the secondary stain (red/pink)

Gram positive - Multiple layers of peptidoglycan, teichoic acid (acidic polysaccharide, and lipoteichoic acid

Thicker

Many layers of peptidoglycan

No outer membrane

Contains teichoic acids (acidic polysaccharide)

Contain lipoteichoic acid

Can be stained ( purple/Violet) with gram stain, and retains the primary stain

29. What are sex pili?

Flagella like structure that transfers genetic matierals between cells of two microbes.

30. Why do we stain cells?

To add contrast to microbes to visualize them.

31. What are decomposers?

the microorganisms that recycle nutrients by breaking down dead matter and waste are ____

32. What is genetic engineering?

The insertion of genes into cells to produce chemicals ( not made naturally)

33. What is Biotechnology?

Using microorganisms in the production of foods, new substances, such as vaccines, antibiotics and viatamins

34. What are viruses?

an infective agent that typically consists of a nucleic acid molecule in a protein coat, is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host

35. Know the different heirachies or organization e.g. domain, kingdom ect

Dear King Phillip Came Over For Good Soup

Domain

Kingdom

Phyllum

Class

Order

Family

Genus

Species

36. What is a parasite?

an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.

37. What is malaria?

Plasmodium

38. What is bioremediation?

The introduction of microorganisms into the environment to restore stability.

39. What are the SIX's of studying microbes?

Inoculation

Incubation

Isolation

Identification

Information Gathering

Inspection

40. Know different types of media

3 types of media

1. Physical state

a. Liquid-broth

b. Semi solid- slants

c. Solid- agar plate

2. Chemical composition

a. Synthetic- artificial, known ratie

b. Non synthetic- natural, ratio unknown

c. Semi synthetic - partly synthetic and non synthetic complex media

d. Selective media- Contains one or more agents that inhibit growth of some microbes and encourage growth of the desired microbes—ex. Mannitol salt agar (MSA) for staph

3. Functional

a. General purpose, ex. Nutrient agar (na), tryptocase soy agar (tsa)

b. Selective media- Contains one or more agents that inhibit growth of some microbes and encourage growth of the desired microbes—ex. Mannitol salt agar (MSA) for staph

c. Differential media - allows groth of several types of microbes and displays visable differences among those microbes ex. Mackonkey (can be selective or differential)

d. Enriched media- growth factors added ex.blood agar

e. Reducing media(thioglycollate media) - thioglycollic acid which reduces 02 concentration - why is a reduced media also called a thioglycollate media? Thiglycollic acid is added which reduces 02

f. Carbohydrate fermentation media - sugars realease hydrogen ion making it more acidic

41. What is inoculation?

Introduction of a sample into a container of media to produce a culture

42. What is a pure culture?

Media that contains only one kind of microbe.

43. What is a selective culture?

Media that contains one or more agents that inhibit growth of some microbes and encourage growth of desired microbe.

44. What is differential culture?

Media that allows growth of several types of microbes and displays visible differences among those microbes.

45. What is the medium for growing fastidious bacteria?

Enriched media

46. What is a synthetic nutrient media?

Media that is artificial. Contains pure organic compounds and inorganic compounds in an exact formula whose ration is known.

47. When do we use mannitrol salt agar

Selective media for staphylococcus

48. Why do we stain microbes?

Increases their contrast, making them more readily visible

49. What are basic dyes?

Basic dyes are positively charged chromophore

50. What are examples of basic dyes?

Methylene, sufranin, Carbol fuschin

51. What medium determines if bacteria is motile?

MIO (Motility Indole Ornithine) SIM (Sulfide Indole Motility)

52. What media do we use for fungi?

general purpose media

53. Bacteria appendages for adhering to surfaces?

Pili and Fimbriae. They do not assist in motility on attachment and adhering.

54. What is a structural stain?

can be used to study and identify the structure of bacteria

55.Flagella all over the surface

peritrichous

56. What is peptidoglycan and where do we find it?

Peptidoglycan is a cell wall component.

it is an insoluble,porous,polymer of great srength and ridgity

57. Bacteria with mycolic acid is called?

Mycobacterium

58. What is bacteria endospore?

An endospore is a dormant, tough, and non-reproductive structure produced by certain bacteria from the Firmicute phylum.

59. Flagella from same end of bacteria is called?

monotrichous (one flagella) or lophotrichous (cluster at one end)

60. What is lysozyme?

- Organells that contain a team of hydrolytic enzymes for all 4 macromolecules

o Example- carbohydrate, protease,lipase,nuclease (the enzymes that break down the four macromolecules)

o When lysomes cannot produce carbohydrate will result in Pompe's disease

o When not produce lipase Tay Sachs disease

61. What is the mordant in gram stain?

helps increase contrast = grams iodine

62. What is a bacterial plaque?

. a clear circular zone in an otherwise confluent growth of bacteria on an agar surface resulting from bacterial lysis by bacterial viruses.

63. what are prions?

Prions are a type of virus that is made of misfolded proteins and do not contain nucleic acid. Common in animals.

64. What are viroids?

A type of virus made up of a short piece of naked RNA and no protein coat. Common in plants

65. What is lysogenic phase of manipulation?

Lysogenic Cycle

Viral multiplication does not cause lysis and death of the host cell.

1. Attachment

2. Entry - penetration

3. Uncoat

4. Integration

66. What is lytic cyle of manipulation?

Lytic cyle - results in death of host cell

1. Adsorption - Binding of virus to specific molecule on a host cell.

2. Penetration - Genome enters the cell.

3. Uncoating - The viral nucleic acid is released from the capsid.

4. Integration

5. BioSynthesis - Viral components (proteins and genome) are produced

6. Assembly - new viral particles are assembled.

7. Release - Assembled viruses are released by exocytosis or cell lysis.