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Question 1

Rod Shape bacteria (E. coli) length

Answer 1

1-1.5 micrometers wide
2-6 micrometers long

Question 2

Streptococcus (Round) length

Answer 2

0.8-1 micrometer in diameter
Divide in only one division plane, and they remain attached to one another after division

Question 3

Staphylococcus (Round) length

Answer 3

they stay attached together during cell division but they divide in random division planes.

Question 4

Bacterial cell envelope

Answer 4

The substance outside of the cell wall that contains the cell

Question 5

Perieable barrier

Answer 5

lets some things in and out, but not others

Question 6

Bacterial plasma membrane

Answer 6

Inner most layer in the cytoplasm
Required for all living cells if broken the cell dies

Question 7

Anchor point

Answer 7

certain receptors for detecting and responding to chemicals in the surrounding environment, for transport systems

Question 8

The plasma membrane is__

Answer 8

asymmetric and made of two major components: lipids that make up the amphipathic bilayer
membrane proteins

Question 9

Membrane proteins

Answer 9

either peripheral (loosely connected to membrane and easily removed), or integral proteins (which pass through the membrane and are amphipathic, like the lipids- where hydrophobic regions anchored in the core of the hydrophilic core of the lipid bilayer)

Question 10

Integral proteins

Answer 10

carry out some of the most important functions in the membrane; many of them are transport proteins used to move materials in and out of the cell, while others are involved in energy conserving processes
The integral proteins with regions exposed to the outside of the cell, allow for interaction of the cell with the outside environment

Question 11

Microbes

Answer 11

need a source of energy to thrive and survive: high energy ATP molecule is the energy currency

Question 12

Facilitated diffusion:

Answer 12

substances move across the plasma membrane through transport proteins that are carriers or channels

Question 12

Active transport:

Answer 12

transport of solutes to higher concentrations (against a gradient).

Question 13

Primary Active transport

Answer 13

use energy provided by ATP hydrolysis to move substances against concentration gradient without modifying them
uniporters: move a single molecule across membrane

Question 14

Secondary Active transport

Answer 14

potential energy of ion gradients to transport substances against concentration gradient without modifying them
They are all cotransporters (they move two substances simultaneously; there is antiporter and symporter)

Question 15

Bacterial cell wall

Answer 15

essential for almost all bacteria since it helps maintain shape and protect the cell from osmotic lysis
(like a balloon popping)

Question 16

Gram positive vs Gram Negative

Answer 16

(remember that Gram positive bacteria stains purple, Gram negative bacteria stains red or pink)
Gram negative bacteria are more diverse and more common than gram positive bacteria
This differential staining is actually due to the fundamental differences in the structure and arrangement of the cell walls

Question 17

Cell walls of typical Gram positive bacteria consist of

Answer 17

a single 20-80 nanometer thick layer of peptidoglycan outside the plasma membrane

Question 18

Gram negative bacteria have two distinct layers, a____

Answer 18

2-7 nm thick layer covered by a 12-14 nm thick outer membrane

Question 19

Capsules

Answer 19

well organized and not easily washed off
Mostly made of polysaccharides, and other materials
They can be seen by negative staining using a light microscope

Question 20

Slime layer

Answer 20

Helps to attach to the surface, including host tissues
Made of polysaccharides normally, but not easily observed under a light microscope

Question 21

S-layers

Answer 21

protects the cell against pH and ion changes, osmotic stress, predatory bacteria and enzymes. It also maintains the cell shape and rigidity, protecting against host defenses for some pathogens.
Only in some bacteria
Made of protein

In gram negative bacteria, the S layer adheres non-covalently to the outer membrane
In gram positive bacteria, the S layer is associated with the surface of peptidoglycan

Question 22

Bacterial cytoskeleton

Answer 22

Made of protein filaments that are similar to actin and tubulin in eukaryotes
Crowded space, the liquid component is the cytosol

Viscosity is ten times greater than water due to macromolecular crowding, affecting physical and chemical processes

Question 23

Inclusions

Answer 23

Common in all cells

Question 24

Bacterial Cytoskeleton Components

Answer 24

Inclusions
Bacterial ribosomes
Nucleoids
Plasmids

Question 25

how bacterial chemotaxis works

Answer 25

Bacteria do not move around aimlessly, but rather they use motility to move away from harmful substances. The movement in response to chemical gradients is known as chemotaxis

move in response to non chemical cues like temperature
light
oxygen
osmotic pressure

Question 25

Bacterial Attachment and Movement

Answer 25

Bacterial pili and fimbriae
Flagella

Question 26

properties of bacterial endospores

Answer 26

Endospores– dormant cells that are formed within a mother cell.
They are only produced by certain species of bacteria:
rods; Bacillus and Clostridium genera
cocci; Sporosarcina

Question 27

process of sporulation

Answer 27

Plants and fungi produce a large amount of spores for reproduction whereas bacterial spores are formed individually that are later germinated into a single cell.

Bacterial spore formation is not a reproductive strategy (unlike in plants and fungi), but rather it is a survival strategy during adverse conditions.

Question 28

Sporulation cycle

Answer 28

Starts when growth slows down due to nutrient limitations. It is a survival mechanism that allows the bacteria to produce a dormant cell until nutrients become available again.

two stages: vegetative growth and survival as an endospore. Vegetative growth is the normal continuous cell growth cycle and division.

Question 29

Sporulation cycle

Answer 29

1. Chromosomal replication
2. Asymmetric cell division– a septum forms off-center, creating two unequal cells
3. Engulfment – mother cell engulfs the smaller cell, resulting in sm cell having two membranes
4. Cortex formation– between the two membranes, a thick peptidoglycan layer (cortex) forms
5. Coat formation– protective coat made of 80 different proteins
6. Maturation
7. Release– the mother cell/ sporangium lyses (breaks down), releasing the mature endospore into the environment