Mary Jones and Geoff Jones Solutions for Chapter: Biotechnology, Exercise 3: End-of-chapter questions
Mary Jones Biology Solutions for Exercise - Mary Jones and Geoff Jones Solutions for Chapter: Biotechnology, Exercise 3: End-of-chapter questions
Attempt the practice questions on Chapter 21: Biotechnology, Exercise 3: End-of-chapter questions with hints and solutions to strengthen your understanding. Cambridge IGCSE® Biology Coursebook Third Edition solutions are prepared by Experienced Embibe Experts.
Questions from Mary Jones and Geoff Jones Solutions for Chapter: Biotechnology, Exercise 3: End-of-chapter questions with Hints & Solutions
Copy and complete these sentences, using the words below. You may use each word once, more than once or not at all.
| amylase | bacterium |
| biofuel | catalase |
| protease | ethanol |
| Bread making | Carbon dioxide |
| oxygen | glucose |
| starch | Sulphur dioxide |
Yeast is a single-celled____. It can respire anaerobically, breaking down glucose to form ____ and the gas _____, _____. To make ethanol for use in _____, yeast is provided with sugars that have come from crops such as maize. To make bread, yeast is mixed with flour and water. The enzyme _____ breaks down starch in the flour, producing _____ that the yeast uses in respiration.This forms _____, ______which makes the bread rise.
Outline one example of the use of genetic engineering to increase yield in a crop plant.
Genetic engineering can be used to improve the yields of crop plants such soya. Describe the possible advantage and disadvantage of this.
Enzymes are used commercially to extract juice from the apple. The diagram below shows two containers of apple juice. One contains juice extracted using an enzyme and the other without an enzyme.
Regarding the diagram, compare the volume and appearance of the two juices extracted.
Some students investigated the effect of pH on the production of apple juice using the same enzyme.
Construct a graph to show the effect of pH on the production of apple juice using this enzyme.
Some students investigated the effect of pH on the production of apple juice using the same enzyme.
State the optimum pH for the action of this enzyme.
Enzymes are used commercially to extract juice from apples. Some students investigated the effect of pH on the production of apple juice using the same enzyme.
Describe and explain the effect of pH on the production of apple juice, using this enzyme.
Enzymes are used commercially to extract juice from apples. Some students investigated the effect of pH on the production of apple juice using the same enzyme.
- The apples were chopped up and formed into a smooth pulp.
- The pulp was divided into samples. Each sample was adjusted to a different pH.
- Enzyme was stirred into each sample of pulp and left to stand for 10 minutes for the enzyme to react.
- The mixtures of pulp and enzyme were then filtered for 20 minutes to collect the juice. The volumes of apple juice collected, are shown in the table.
Suggest the factors that need to be controlled in this investigation.
