Lecture 3

Question 1

How is bacterial growth defined?

Answer 1

An increase in cell number

Question 2

What are the 2 types of Bacterial Growth?

Answer 2

Anabolic and Catabolic

Question 3

Anabolism grows from what to what?

Answer 3

Small to large

Question 4

Catabolism grown from what to what?

Answer 4

Large to small

Question 5

What is binary fission?

Answer 5

When a cell divides into 2 new cells

Question 6

What is generation time?

Answer 6

Time required for cells to double structural components

Question 7

What is exponential growth?

Answer 7

When the cells double per unit time

Question 8

What are 2 approaches to the study of growth under controlled conditions?

Answer 8

Batch Culture & Continuous Culture

Question 9

Difference between batch culture and continuous culture?

Answer 9

Batch - fixed substrate is added - Continuous a continuous amount of growth medium

Question 10

List the 4 phases of growth

Answer 10

1. Lag
2. Exponential
3. Stationary
4. Death

Question 11

Main Reason for the lag phase to occur?

Answer 11

New conditions - adaptation

Question 12

Growth will remain in the lag phase until the population reaches…

Answer 12

10 to the 6 cells/ml

Question 13

2 reasons for stationary phase

Answer 13

Carbon and energy source

Nutrients are used up

Question 14

What is endogenous metabolism?

Answer 14

Growth on dead cells

Question 15

Which is slower death phase of exponential phase?

Answer 15

Death phase

Question 16

What are capnophiles?

Answer 16

Microbes that grow better at high CO2 concentrations

Question 17

What are porins?

Answer 17

Part of the outer membrane - allows the passage of molecules

Question 18

What are autolysins?

Answer 18

Enzymes that create small openings in the macromolecular structure of the wall

Question 19

What is the periplasm?

Answer 19

Fluid filled space between the outer membrane and the plasma membrane.

Question 20

What is the most important differential stain used in bacteriology?

Answer 20

Gram Stain

Question 21

Two major groups of Gram Staining?

Answer 21

Gram-positive and Gram Negative

Question 22

Colour of gram-negative bacteria at end of Gram Staining?

Answer 22

Red - pores increase so the violet colour leaves

Question 23

Colour of Gram-Positive Bacteria at end of Gram Staining?

Answer 23

Violet - Pores shrink so the colour stays

Question 24

True or false - gram staining must be performed on cultures less than 24hrs old?

Answer 24

True

Question 25

What is peptidoglycan?

Answer 25

A macromolecular network making up the bacterial cell wall

Question 26

Describe Peptidoglycan in Gram Positive bacteria cell wall?

Answer 26

Many layers
Thick
Teichoic acid

Question 27

Describe Peptidoglycan in Gram Negative bacteria cell wall?

Answer 27

Thin

No teichoic acid

Question 28

Ideal numbers on plate for a viable count?

Answer 28

30-300 cfu

Question 29

Does Gram Positive or Gram Negative look like an ice cream sandwich?

Answer 29

Gram Negative

Question 30

Does Gram Positive or Gram Negative look like 2 layer jello?

Answer 30

Gram Positive

Question 31

Polymerization reactions through which macromolecules are made from monomers are the main reactions of what?

Answer 31

Cell Synthesis

Question 32

Generation times vary widely among organisms. Many bacteria have generation times of _____ but a few very rapidly growing organisms can divide in as little as ______

Answer 32

1-3h, 10 m

Question 33

The vessel that is used as a growth container in continuous culture is called a

Answer 33

Bioreactor or a Chemostat

Question 34

T or F In a chemostat one can control the flow rate, maintain a constant substrate concentration, as well as provide continuous control of pH, temperature, and oxygen levels. This allows control of the rate of growth, which can be used to optimize the production of specific microbial products such as ethanol.

Answer 34

True

Question 35

Defined as one that is able to divide and form offspring, and the usual way to perform a viable count is to determine the number of cells in a sample capable of forming colonies on a suitable agar medium.

Answer 35

viable count

often called the plate count, or colony count.

Question 36

In this type of counting procedure is that each viable cell can yield

Answer 36

One colony

Question 37

consists of a repeating disaccharide attached by polypeptides to form a lattice that surrounds and protects the entire cell. The disaccharide portion is made up of monosaccharides called N- acetylglucoseamine (NAG) and N-acetylmuramic acid (NAM) (from murus, meaning wall), which are related to glucose.

Answer 37

Peptidoglycan

Question 38

The peptidoglycan is bonded to lipoproteins in the outer membrane and is in the

Answer 38

periplasm

Question 39

T OR F - The periplasm contains a high concentration of degradative enzymes and transport proteins. Gram-negative cell walls do not contain teichoic acids.

Answer 39

TRUE

Question 40

Part of the permeability of the outer membrane is due to proteins in the membrane called

Answer 40

PORINS

Question 41

Staining procedures that elicit differences between bacterial cells or parts of a bacterial cell are termed

Answer 41

Differential staining techniques.

Question 42

The coloration of bacteria by applying a single solution of stain to a fixed smear is termed

Answer 42

Simple staining.