PNP WK2

Question 1

What is bacteria?

Answer 1

Single celled, prokaryotic, contain a cell wall and membrane and DNA.

Question 2

What is the difference between gram +ve/ gram -ve bacteria?

Answer 2

+ve: simple cell wall, lack a cell wall but has a thicker layer of peptidoglycan
-ve: complex cell wall, contains a cell wall and has thin layer of peptidoglycan and lipo-polysaccharide outer layer

Question 3

What are the different types of shapes for bacteria?

Answer 3

Spirilla: spiral
Bacilli: rod shaped
Cocci: spherical
Staph: irregular clusters
Strep: chain clusters
Diplo: pair clusters

Question 4

What is a virus?

Answer 4

Comprise of nucleic acid molecule (DNA or RNA), encased in a protein coat (a capsid), can only multiply inside living host

Question 5

What is fungi?

Answer 5

Eukaryotic, multicellular, contain membrane-bound nuclei, release enzymes causing topical redness, purpose is to degrade organic matter

Question 6

What is protozoa?

Answer 6

eukaryotic, unicelluar cells, without a cell wall, PARASITES

Question 7

What are the chain of infection steps?

Answer 7

1. Infectious agent: what causes the diseases
2. Reservoir: where infectious agent is sustained in (body of water, organism)
3. Portal of exit: where and how it leaves reservoir
4. Mode of transmission: how agent moves while staying viable
5. Portal of entry: where agent enters the body
6. Susceptible host: how likely the agent is to cause disease due to the host’s immunity

Question 8

What is the human microbiome?

Answer 8

All microbiotas residing in/on the human body after years of exposure creating communities of organisms
- Plays important role in metabolism and immunology of persons

Question 9

What are the different features of antibiotics that can be used to fight bacterial cells?

Answer 9

• Target bacteria DNA code replication (only one chromosome present in bacteria)
• Target cell wall so water rushes in and compromises cell (has a peptidoglycan cell wall)
• Target protein synthesis (ribosomes use mRNA for protein)
• Targets folate enzyme (used for protein synthesis), and becomes an inhibitor

Question 10

What is the difference between exo/endo toxins?

Answer 10

Exo: Are proteins produced inside bacteria, are secreted into surrounding areas following lysis, UNSTABLE

Endo: -ve cells ONLY, lipid portion of lipopoly, are released when cell dies and wall breaks, heat tolerant

Question 11

What are the main mechanisms of actions of antibiotics?

Answer 11

• disrupts cell wall synthesis causing lysis
• inhibits protein synthesis, affects ribosomes
• inhibits bacterial DNA synthesis, blocks transcription
• affects folic acid synthesis, won’t produce proteins for growth

Question 12

What are examples of antibiotics that disrupt cell wall synthesis?

Answer 12

Pencillins, cephalosporins, Carbapenems, glycopeptides (vancomycin)

Question 13

What are examples of antibiotics that inhibit protein synthesis?

Answer 13

Aminoglycosides (gentamicin), tetracyclines, macrolides, erythro/clindamycin

Question 14

What are examples of antibiotics that inhibit DNA synthesis?

Answer 14

Quinolones and Rifampin

Question 15

What are examples of antibiotics that affect folic acid synthesis?

Answer 15

Sulfonamides and trimethoprim

Question 16

What is innate resistance?

Answer 16

• Bacteria that is naturally resistant to some antibiotics,
• misuse of antibiotics increases the rate of antibiotic resistance

Question 17

What is the mechanism of resistance of bacteria?

Answer 17

A bacteria mutates to become more resistant to its environment and to make up for lack of genetic diversity, and is more likely to survive and thus reproduce.

Question 18

What is the mechanism of action for antimycotics?

Answer 18

Disrupt fungal cell membrane synthesis and integrity
Triazole and Imidazole

Question 18

How does bacteria resist antibiotics?

Answer 18

• Actively removing antibiotic from cell
• Producing enzymes that inhibit antibiotic
• Us different metabolic pathways to those being inhibited by antibiotic
• Altering antibiotic binding site

Question 19

What is the mechanism of action for a virus?

Answer 19

• Capsid covered in protein spikes that attach to the host receptor cells facilitate the virus fusing into the cell and ultimately replicate
• genetic material enters the cell and takes over control of the host cell to synthesize protein and release new virus

Question 20

What are different antiviral agents?

Answer 20

1. Fusion inhib.: bind to surface proteins that prevent fusion with membrane- Enfuvirtide
2. Penetration inhib.: inhibits enzymes that penetrate cells- Amirvir
3. Synthesis inhib.: inhibits enzymes that copy DNA (Aciclovir) and RNA (Abacavir)
4. Assesmbly inhib.: inhibits viral assembly- Amantadine
5. Release inhib.: inhibits neuraminidase enzyme (entry enzyme)- Osteltamirvir

Question 21

What are the different types of mycosis (fungal infections)

Answer 21

1. Systemic: internal system is infected (respiratory tract)
2. Subcut: entered via wound
3. Cutaneous: epidermis, hair or nails
4. Superficial: out epi and hair

Question 22

What are the stages of infection?

Answer 22

1. Incubation: organisms growing and multiplying
2. Prodromal: person is infectious, non specific signs of disease
3. Illness: Presence of specifics symptoms of diseases
4. Convalescence: Recovery from infection