Fermentation Of Carbohydrates Pg 81-84 Flashcards

1
Q

Fermentation is an anaerobic form of

A

Respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Carbohydrates are organic molecules of various molecular weight which are composed of _____, ______, and _____.

A

Carbon, hydrogen, and oxygen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In general, carbohydrates have the formula ________.

A

(CH2O)n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

____ &____ are common carbohydrates

A

Sugars and starches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Bacteria may produce exoenzymes which are secreted ______ the cell to break down large carbohydrate molecules (polysaccharides, disaccharides and monosaccharides).

A

Outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The primary monosaccharide for energy is glucose, however, alternative monosaccharides can be utilized, such as:

A

Ribose, fructose, and galactose, if glucose is absent or low in concentration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The monosaccharides and disaccharides may be brought across the cell membrane by

A

Permeases (transfer enzymes) or by diffusion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Once inside the cell, endoenzymes continue the molecular breakdown, releasing what into the cell?

A

Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Many bacteria are capable of fermentation. This is a process in which oxygen is not required, and there is an incomplete breakdown of food, such as:

A

Carbohydrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In fermentation, the products are often an _______ or an ______ with or without CO2 (gas).

A

Acid or alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Fermentation:
Sugar———> Pyruvic acid ———> ?

A

Various end products + ATP (mostly organic acids [sometimes alcohols] with or without CO2).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why are these tests a good tool to identify certain bacteria?

A

Because not all bacteria ferment every carbohydrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fermentation broths typically contain a specific carbohydrate, such as:

A

sucrose, glucose, lactose, or mannitol.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The broths also contain non fermentable nutrients, such as:

A

Proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

If the bacteria use all of the carbohydrate or cannot use the carb, they may utilize a ____ as a source of energy, releasing amines which form weak bases in ____ solutions.

A

Protein
Water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Phenol red is included in the medium to distinguish:

A

Phchange

17
Q

Which tubes have been inverted in the culture tubes to collect any gas which might evolve during fermentation.

A

Durham tubes

18
Q

In this exercise are glucose and sucrose the only possible sample carbs that can be used?

A

No, there are many other carbs that can be used.

19
Q

Procedure: what did we use in the three tubes of glucose, sucrose, and lactose broths?

A

E. Coli
A. (Alcaligenes) faecalis
S. Aureus

20
Q

Culture tubes were placed in the incubator at 37 degrees Celsius for how long?

A

24-48 hours

21
Q

False results may occurs if tubes are left to incubate for over a week, why?

A

The longer the incubation time, the higher risk of contamination by other microbes, which leads to in accurate results.