Lecture 1 - Intro to Bacteria

Question 1

Eukaryotic pathogens include _____ and _____.

Answer 1

FUNGI

PARASITES

Question 2

Single cell fungi are classified as _____, while multicellular are classified as ______ and mushrooms.

Answer 2

YEASTS

MOLDS

Question 3

Parasites can be both _____cell and _____cellular.

Answer 3

Single

Multi-cellular

Protozoa are examples of single cell

Question 4

_______ are examples of single cell, while ______ are examples of multicellular Parasites.

Answer 4

Protozoa

Helminths

Question 5

Mycobacterium and Mycoplasma are ____ to gram staining. The only way to stain them is with an ____-____ stain.

Answer 5

REFRACTORY

Acid-Fast

Question 6

Gram + bacteria lack an _____ membrane, but have a _____ cell wall, while Gram - bacteria are just the opposite.

Answer 6

Outer

Thick

Question 7

The bacterial cell wall is comprised of ______. A major difference between bacterial and human cells is the presence of ____ in human cells but not in bacterial cells (because bacterial cells have a cell wall and human cells do not.) This provides rigidity and osmotic protection in human cells.

Answer 7

Peptidoglycan

Sterols

Question 8

Keep in mind that all bacterial cells have a cell wall EXCEPT for ______.

Answer 8

Mycoplasma

Question 9

Each layer of bacterial cell walls (gram -
typically only have 1 layer) consist of chains of repeating ______ units that encircle the cell and are cross-linked through ______ bridges (beta____-____ linkages) formed by a ______ enzyme

Answer 9

Disaccharide

Peptide bridges

beta 1-4

Transpeptidase

Question 10

Penicillin inhibits ______, which disrupts the integrity of the cell wall.

Answer 10

Transpeptidase

Question 11

All gram + bacteria contain ______ acid which can either be associated with the outermost layer of the cell wall or pass through all layers of the cell wall down to the cytoplasmic membrane. The former is called _____ _____ acid, while the latter is referred to as _______ acid. Keep in mind that they both function as _______ (binding - which is considered a virulence factor.)

Answer 11

Techoic

Wall Techoic acid

Lipotechoic acid

Adhesins

Question 12

Gram - bacteria have an asymmetric outer membrane consisting of _____ (LPS), ______ (non-selective diffusion channels that select on the basis of size) and phsopholipids.

Answer 12

Lipopolysaccharides

Porins

Question 13

One of the 3 components of LPS, ____A is a highly toxic ______toxin.

Answer 13

Lipid A

Endotoxin

Question 14

When a gram - bacteria lysis, Lipid A is released and binds LPS-_____ protein in the blood. This complex can bind to ____ on macrophages which increases the release of _____. Too large of an increase can lead to sepsis.

Answer 14

LPS-binding protein

CD14 on macrophages

Cytokines

Question 15

Clinical symptoms of Bacterial sepsis include:

1. Suspected or documented ______
2. _____ or hypothermia
3. Tachycardia
4. Tachypnea

Answer 15

1. Suspected or documented Bacteremia

2. Fever or hypothermia

Question 16

Capsules confer bacteria with a virulence factor because they help prevent _______ (A capsular covering prevents recognition of opsonizing proteins via stearic hindrance.)

Answer 16

Phagocytosis

Question 17

Bacteria can also produce slime which is also a virulent factor as it facilitates formation of _______.

Answer 17

Biofilm

Question 18

Flagella facilitate bacterial _____, which can be very important in virulence.

Answer 18

Motility

Question 19

There are 2 types of Pili (adhesins):

1. ____ pili
2. ____ pili

Answer 19

1. Sex pili

2. Common pili

Question 20

Common pili facilitate Bacteria-_____ cell interactions –> virulence factor. Sex pili facilitate Bacteria-_______ cell interactions –> conjugation.

Answer 20

Human

Bacteria

Question 21

One of the factors that affects bacterial growth is temp. For example, mycobacterium leprae grows well at ____ temperature, while M. Tuberculosis requires warmer temps (closer to 37 C.)

Answer 21

Room

Question 22

Growth rate of bacteria is calculated by the equation: # of ______/hours. Generation time = time it takes for a bacterial population to double.

Answer 22

Generations

Question 23

Plasmids are _______ replicating (self-replicating.)

Answer 23

Autonomously

Question 24

Two mechanisms of genetic variability in bacteria are _______ and ______ gene transfer. Variability is of concern because it can increases pathogenicity or confer antibiotic resistance.

Answer 24

Mutagenesis

Horizontal gene transfer

Question 25

Conjugation requires that a bacterium has a conjugative _____, which contains “_____ genes” that facilitate the transfer to another bacterium. In the end, both the donor and recipient have the conjugative ____.

Answer 25

Plasmid

“Transfer genes”

Plasmid

Question 26

______ recombination is much more efficient and thus is more common.

Answer 26

Homologous