The Uses of Microorganisms in Biotechnology

Question 1

Brewing

Answer 1

To make beer, yeast is added to a type of grain (barley) and other ingredients. The yeast respires anaerobically using the glucose from grain and produces alcohol and CO2.

Question 2

Baking

Answer 2

Yeast makes bread rise. The CO2 produced by fermentation of sugars in the dough makes sure it doesn’t stay flat.

Question 3

Cheese making

Answer 3

Relies on Rennet, which contains the enzyme chymosin which clots milk.

Traditionally, we use chymosion from extracting rennet from the lining of calves stomachs. But now chymosin is obtained from yeast cells that are genetically modified to produce the enzyme.

Also involves lactic acid bacteria, which converts the lactose in the milk into lactic acid which makes it turn sour and contributes to its solidifying.

Blue cheese involves fungi

Question 4

Yoghurt

Answer 4

Involves lactic acid bacteria which clot milk and cause it to thicken.

Question 5

Penicillin

Answer 5

In times of stress, the fungi Penicillium produces an antibiotic, penicillin, to stop bacteria growing and competing for resources. Penicillin is one of the most common antibiotics used in medicine, so we produce it on a massive scale.

Question 6

Insulin

Answer 6

Made by genetically modified bacteria, which have the gene for human insulin inserted into their DNA.

Question 7

Bioremediation

Answer 7

Use organisms to remove pollutants.

Pollutant removing bacteria that occur naturally at a site are provided with extra nutrients and enhanced growing conditions allowing them to multiply and thrive.

Question 8

Single-cell protein

Answer 8

A source of protein which acts as a food source.

Can be grown on waste products/grown quickly and cheaply/cultured anywhere/healthier.

Dont like the idea/not same flavour