Under the Sea

Question 1

6 steps of infectious disease process

Answer 1

1) encounter
2) entry
3) spread
4) multiplication
5) damage
6) outcome

Question 2

2 different processes of entry into a host

Answer 2

1) inhalation or ingestion (body cavities that are contiguous with outside)
2) penetration of microorganisms into deeper tissues after crossing the epithelial barrier (insect bites, cuts and wounds, organ transplants, blood transfusions)

Question 3

Not considered inside the body

Answer 3

Nose, Mouth, Respiratory Tract, Alimentary Canal, Anus, Female Genital Tract, Urinary Tract

Question 4

Penetration of bacteria into epithelial cells involves 2 steps:

Answer 4

1) attachment to specific receptors

2) internalization

Question 5

Spread of infection has 2 meanings:

Answer 5

1) lateral propagation to contiguous tissues

2) dissemination to distant sites

Question 6

Microbes must overcome ______ to multiply and spread

Answer 6

host defenses

Question 7

______ is important in establishing an infection (varies with different organisms)

Answer 7

Inoculum size

Question 8

4 possible outcomes of a host-parasite interaction

Answer 8

1) host wins out and clears infection
2) parasite overcomes host
3) host and parasite adapt to each other
4) Neither host or parasite win (chronic infection can continue indefinitely)

Question 9

Damage to host can be caused by _______ or by _______ or both.

Answer 9

the infectious agent or by host response

Question 10

Great majority of microorganisms are _________. They coexist without causing harm. It can be difficult to identify a bacterium as such.

Answer 10

commensal.

Question 11

Gram positive bacteria have a thick cell wall made up of _____, which is a ________.

Answer 11

murein, peptidoglycan

Question 12

Murein is made up of long chains of ____________ and ___________ linked together by short polypeptides.

Answer 12

N-acetylmuramic acid and N-acetylglucosamine

Question 13

Gram negative bacteria have a ______ of ______ between two membranes (lipid bilayers).

Answer 13

thin layer, murein

Question 14

Outside of the outer membrane of gram negative bacteria is made up of ______ that is different for different bacteria.

Answer 14

Lipopolysaccharaide (LPS).

Question 15

LPS is a toxic ____, even in its purified form

Answer 15

Endotoxin.

Question 16

LPS is made up of a ____ region that faces into the membrane and a ____________ region face out

Answer 16

lipid; polysaccharide

Question 17

The outer _________ region of LPS is highly variable and antigenic.

Answer 17

O-antigen

Question 18

Bactericidal agents ______ bacteria; bacteriostatic agent _______.

Answer 18

kill; inhibit growth

Question 19

_______ and other ________ are antibiotics that affect the cell wall. They are bactericidal

Answer 19

Penicilins and beta-lactams

Question 20

Antibiotics often work by targeting bacterial _________

Answer 20

ribosomes

Question 21

There are 2 subunits to bacterial ribosomes ____ and _____ subunit

Answer 21

30S and 50S

Question 22

30S subunit is primarily responsible for

Answer 22

translation of mRNA

Question 23

50S subunit is primarily responsible for

Answer 23

joining amino acids together and moving the complex along the mRNA molecule

Question 24

Antibiotics can target either ______ & _______ subunit

Answer 24

30S and 50S

Question 25

_______ & _________ inhibit folic and metabolism

Answer 25

sulfonamides & trimethoprim

Question 26

These inhibit protein synthesis (3)

Answer 26

Aminoglycosides, tetracyclines, and erythromycin

Question 27

2 examples of Aminoglycosides..

Answer 27

streptomycin and kanamycin

Question 28

Metronidazole inhibits _____________

Answer 28

DNA synthesis

Question 29

______ are specialized structures on the surface of bacteria that that are involved in adhesion to cells or other surfaces.

Answer 29

Pili (fimbriae)

Question 30

Specialized pili that link a donor cell to a recipient cell during DNA transfer

Answer 30

Sex pili

Question 31

Surface structures used for locomotion

Answer 31

Flagella

Question 32

Flagella cause movement when they rotate ________ and _______ when they rotate __________

Answer 32

counterclockwise; tumbling; clockwise

Question 33

Flagellar movement is used by bacteria for ________

Answer 33

chemotaxis

Question 34

The movement towards substances that attract and away from substances that repel

Answer 34

chemotaxis

Question 35

________ must have oxygen to grow

Answer 35

Strict aerobes

Question 36

________ cannot tolerate oxygen and _________ can grow with or without O2.

Answer 36

Strict aerobes; facultative anaerobes

Question 37

_____ _______ parasites can only grow inside host cells.

Answer 37

Obligate intracellular

Question 38

Ratio between effective and toxic dose of an antibiotic

Answer 38

therapeutic index

Question 39

4 Methods for antibiotic resistance by bacteria

Answer 39

1) enzymes that inactivate the drug
2) inhibit uptake of the drug
3) increase secretion of the drug (pump it out of cell)
4) Modify target of drug

Question 40

Drug resistant genes are often found on ________ that can be transferred from one bacteria to another

Answer 40

plasmids

Question 41

Bacteria must (3 things) to survive as an infectious agent

Answer 41

1) avoid being washed away
2) find a nutritionally compatible niche
3) survive host defenses
4) transfer to a new host

Question 42

Damage to a host as a result of infection can be caused by

Answer 42

1) cell death
2) pharmacological alterations of metabolism
3) survive host defenses
4) transfer to a new host

Question 43

Many structures on the microbial surface consists of repeated molecules, known as..

Answer 43

pathogen associated molecular patterns

Question 44

________ recognize pathogen associated molecular patterns

Answer 44

Pattern recognition receptors

Question 45

Bacteria often classified via their surface antigens (serotype)

a) O refers to..
b) H refers to..
c) K refers to..

Answer 45

a) LPS
b) flagella
c) capsule