Question 1

Which of the following best describes food spoilage in the context of food microbiology?

Accepted Answer

The undesirable change in food caused by the growth of microorganisms, leading to altered taste, odor, appearance, or texture.

Question 2

Which of the following is a critical parameter affecting microbial growth in food preservation?

Accepted Answer

The water activity ($$a_w) of $$the food

Question 3

A food product is classified as 'perishable' if:

Accepted Answer

It has high water activity ($$a_w) $$and is easily attacked by microorganisms.

Question 4

Which of the following is NOT a common method for controlling microbial growth in food preservation?

Accepted Answer

Increasing the nutrient content

Question 5

Pickling is a preservation method that relies on:

Accepted Answer

Lowering the pH through the addition or production of acids, often via fermentation

Question 6

Which of the following statements about canning is correct?

Accepted Answer

Canning is a process in which food is heated to destroy microorganisms and then sealed in airtight containers.

Question 7

Which of the following is an example of a chemical food preservative classified as 'safe' by the FDA?

Accepted Answer

Sodium chloride (NaCl)

Question 8

Which of the following best defines biotechnology?

Accepted Answer

The use of living organisms or their products to modify human health and the environment.

Question 9

Genetic engineering is best described as:

Accepted Answer

The direct manipulation of an organism's genome using biotechnology.

Question 10

Which of the following is a key advantage of using plasmids as cloning vectors in molecular cloning?

Accepted Answer

They can replicate independently of the host chromosome and often carry selectable markers.

Question 11

A researcher wants to clone a gene into a bacterial host. Which characteristic is LEAST important for the host organism?

Accepted Answer

Ability to photosynthesize efficiently

Question 12

Which of the following best describes the polymerase chain reaction (PCR)?

Accepted Answer

A technique used to amplify specific DNA sequences exponentially.

Question 13

In the production of recombinant human insulin, why are the A and B chains produced separately in bacteria?

Accepted Answer

Because bacteria cannot fold the proinsulin precursor correctly.

Question 14

Which of the following is a practical application of genetic engineering in environmental biotechnology?

Accepted Answer

Using genetically engineered microorganisms to degrade environmental pollutants.

Question 15

A genetically engineered strain of Pseudomonas is used to prevent ice formation on crops. What is the main advantage of this approach?

Accepted Answer

It reduces frost damage by preventing ice nucleation on plant surfaces.

Question 16

Which of the following best describes bioleaching?

Accepted Answer

The use of microbial activity to extract metals from ores.

Question 17

Which molecular technique is used to introduce specific mutations into a gene to study its function?

Accepted Answer

Site-directed mutagenesis

Question 18

A company wants to increase oil recovery from a depleted oil field. Which microbial approach could be used?

Accepted Answer

Using microorganisms that produce biosurfactants to mobilize trapped oil.

Question 19

Which of the following is a real-world example of the use of molecular cloning in medicine?

Accepted Answer

Production of recombinant human insulin for diabetes treatment.

Question 20

Which of the following statements about restriction endonucleases is correct?

Accepted Answer

They are enzymes that cut DNA at specific sequences, enabling molecular cloning.

Food and Industrial Microbiology: Microbial Growth, Food Preservation, and Industrial Biotechnology (lecture 5)

Study Guide - Practice Questions