Study Guide Sheet 1 (pt2)

Question 1

On the gram-negative cell bacteria, which component makes it the endotoxin molecule?

Answer 1

Lipid A

Question 2

On the gram-negative cell bacteria, what creates a periplasmic space between peptidoglycan and the “outer membrane”.

Answer 2

The Lipoprotein layer

Question 3

What is the “cell wall antigen” in Escherichia, Salmonella, and Shigella antigenic tests?

Answer 3

The O Antigen

Question 4

A clump of a few million identical bacteria originating from the same bacterium is called a __________.

Answer 4

A colony

Question 5

Most medically significant bacteria will reproduce about every __________ minutes under optimal conditions.

Answer 5

30 - 60

Question 6

On the gram-negative cell bacteria, what is the site of certain enzymatic processes?

Answer 6

The periplasmic space

Question 7

Describe the types of oxygen utilization.

Answer 7

1. Aerobic – Requires atmospheric oxygen (21%)
2. Microaerophilic – requires reduced oxygen concentration (5-10%)
3. Anaerobic – requires absence of oxygen
4. Facultative – can grow in presence or absence of oxygen

Question 8

What are the optimal temperature, pH, CO2, and humidity for growth of typical medically significant bacteria?

Answer 8

• 35 Degrees Celsius
• 6.8 – 7.4 pH
• No increased CO2 needed (some bacteria need 5 – 7% CO2)
• 60 - 80% humidity

Question 9

When compared to “typical bacteria,” what are the major characteristics that are different for those designated in class as “Atypical” bacteria?

Answer 9

1. Modified cell wall structures, if present
2. Complicated or modified reproductive method
3. Atypical Requires a living host or special highly enriched media

Question 10

The bacteria designated in class as “Typical” belong to the kingdom _________________. Those designated as “Atypical” belong to the kingdom _________________.

Answer 10

Prokaryotes;

Prokaryotes

Question 11

Mould cells that are multicellular long filaments are called ____________. When these cells/structures grow in a mass, they are referred to as _____________.

Answer 11

Hyphae;

Mycelium (i.e. colony)

Question 12

20. Reproductive forms of moulds typically grow on ___________. (what structure)

Answer 12

Reproductive hyphae

Question 13

True/False. Moulds typically grow on artificial media similar to that used for bacteria, except that the media usually contains antibiotics to inhibit viruses. Why?

Answer 13

False, to inhibit bacteria during longer growth periods.

Question 14

Describe a virus? (type of organism, size, reproduction, etc.)

Answer 14

• Not an organism as it is not a living cell
• 18 to 300 nm (.018 - .30 um)
• obligate intracellular parasite
• have either DNA or RNA
• helical (enveloped) or icosahedral (no envelope)

Question 15

What is the inner-most structure of the virus, what is it composed of, and what is its function?

Answer 15

Nucleic acid; RNA or DNA not both; genetic material

Question 16

What is the structure found on the exterior of only certain viruses?

Answer 16

Envelopes

Question 17

What is its structural composition of the envelope around a virus?

Answer 17

• Lipid bilayer from host cell or nuclear membrane

- Glycoproteins (spikes) – site for attachment and serve as antigens

Question 18

What are the primary functions of the virus envelope?

Answer 18

• Lipid bilayer provides protection from the environment
• Proteins are primary site of attachment to host cell surface
• Proteins serve as antigens during infection and as site for antibody attachment

Question 19

Bacterial viruses are structurally similar to animal viruses, but with an additional structure known as the ____________. One significant role of this additional structure is ________________________.

Answer 19

Tail;

The base with enzymatic pins

Question 20

Water comprises about _____% of cell volume

Answer 20

70%

Question 21

As designated with some Atypical bacteria, what does mycoplasma mean?

Answer 21

It has no cell wall

Question 22

Viruses are susceptible to most antibiotics. T/F

Answer 22

False; viruses are not susceptible to most antibiotics

Question 23

Which part of the bacteriophage, can punch a hole in the bacterial cell wall, allowing the nucleic acid to enter.

Answer 23

The base with enzymatic pins

Question 24

Describe the major steps of the virus infection

Answer 24

1. Attachment
2. Penetration and uncoating of nucleic acid
3. Eclipse or synthesis phase
4. Maturation
5. Release

Question 25

The eclipse or synthesis phase of the virus infection, is also known as what?

Answer 25

Translation / Transcription