Tute related SAQs

Question 1

What is enriched differential and selective media explain each with examples.

Answer 1

Enriched media refers to media that contains nutrients required for a wide variety of microorganisms to grow. Differential distinguishes one type to grow from another it allows growth of several types of microbes with phenotypical differences. Selective media only allows the growth of selected organisms containing one or more agents that inhibit growth.

Enriched Horse blood agar
Differential McConkey Agar
Selective: MSA

Question 2

What is food spoilage, intoxication and infection?

Answer 2

Food spoilage - when food deteriorates to a point where it can no longer be consumable for humans

Food intoxication - when food material becomes contaminated and the organism in it produces toxins in the food prior to consumption. E.g. Staphylococcus aureus and Clostridium botulinum

Food infection - when food gets contaminated and the consumption of a certain amount will result in symptoms of disease, usually caused by endotoxins. E.g. E.coli and Salmonella and Campylobacter jejuni.

Question 3

What is fermentation?

Answer 3

Fermentation, in contrast, does not utilize an electrochemical gradient. Fermentation instead only uses substrate-level phosphorylation to produce ATP. The electron acceptor NAD+ is regenerated from NADH formed in oxidative steps of the fermentation pathway by the reduction of oxidized compounds.

Question 4

What antibiotics inhibit cell wall?

Answer 4

B-lactams and Cephalosporins

Question 5

What antibiotics inhibit protein synthesis?

Answer 5

– Aminoglycosides: Streptomycin, neomycin, gentamycin
– Tetracyclines
– Macrolides: Erythromycin