Biotechnology

Penicillium, a fungus, is cultured in fermenters to produce penicillin. The table gives the length of time needed for the fungus mycelium to double in size when different carbohydrates are used. Every other condition was kept the same. What conclusion can be drawn from the data?

May/June 2015

The diagram illustrates several stages in cheese making. During which stage in cheese making are bacteria introduced?

May/June 2015

Fig. 3.1 presents a fetus developing inside a mother’s uterus. The fluid marked C has cells from the fetus in it. A long, hollow needle may be used to draw some of the fluid into a syringe. DNA taken from the cells in this fluid can then be examined to determine the fetus’s sex and to identify mutations.

May/June 2015

Outline the function of microorganisms in yoghurt production.

May/June 2015

The diagram illustrates the apparatus used for the industrial production of penicillin. What is the purpose of the structure labelled X?

May/June 2016

Describe how single cell protein is manufactured on an industrial scale.

May/June 2016

Penicillin is made by the fungus Penicillium. The stages involved are given below. 1 Corn and yeast are added to the fungus. 2 Penicillin is extracted. 3 Penicillin is secreted by the fungus. 4 The product is filtered. What is the order of these stages?

May/June 2018

Outline how a named type of microorganism is involved in the production of each of the following products: yoghurt; bread.

May/June 2018

Which of these can be made using bacteria?

May/June 2019

What are the optimum conditions in a fermenter for the large-scale production of penicillin?

May/June 2019

Which product is manufactured using bacteria?

May/June 2021

Yoghurt is a product made from milk.

May/June 2021

The graph illustrates the mass of $\textit{Penicillium}$ grown in a fermenter together with the mass of antibiotic produced. At what point is the $\textit{Penicillium}$ producing antibiotic at the fastest rate?

May/June 2022

The diagram illustrates a fermenter used for culturing the fungus Penicillium in order to make penicillin. What is the role of the outer water jacket?

May/June 2023

Bacillus subtilis is a bacterium species that is widely employed in biotechnology. It can be used to produce the protein lipase for industrial purposes.

May/June 2024

Pectinase is an enzyme made by fungi. In industrial production on a large scale, pectinase is produced by growing fungi in fermenters.

May/June 2025

Milk can be processed in different ways to make foods. Which processes take place in both cheese and yoghurt production?

Oct/Nov 2015

Foods may be produced by processing milk in different ways. Which processes take place in both cheese and yoghurt production?

Oct/Nov 2015

The diagram illustrates an industrial fermenter. Why is sterile air necessary for the microorganisms inside the fermenter?

Oct/Nov 2016

Fig. 7.1 depicts a fermenter that is being used to make an antibiotic.

Oct/Nov 2017

The following stages are part of yoghurt production: 1 liquid cooled rapidly; 2 liquid kept at $40-45\,^\circ\text{C}$ for 3 hours; 3 culture of bacteria added to liquid; 4 liquid pasteurised. In what sequence do these stages take place?

Oct/Nov 2018

Which comparison statement about the production of single cell protein and the production of protein in meat is incorrect?

Oct/Nov 2020

A fermenter is used to produce penicillin. Why is it necessary to keep stirring continuously during fermentation?

Oct/Nov 2020

The graph illustrates how lactose concentration changes over 48 hours as milk is converted into yoghurt.

Oct/Nov 2022

The antibiotic penicillin is made by a fungus named Penicillium. The graph illustrates how the masses of Penicillium fungus, penicillin and sugar change in a fermenter during the manufacture of one batch of antibiotic. What does each curve on the graph represent?

Oct/Nov 2023

Biofuels are derived from plant material or animal waste. They act as substitutes for fossil fuels such as petrol and oil. Fossil fuels formed over very long timescales, millions of years ago. Biofuels may be a sustainable resource, or they may not be. Fig. 6.1 provides data on alcohol production and deforestation in Brazil from 2012 to 2016.

Oct/Nov 2025