Biological Molecules
Overview
Your body is a chemical factory. Every second, thousands of reactions build new molecules, break others apart, and release the energy that keeps you alive. The raw materials for all of this come from just three families of large biological molecule: carbohydrates, proteins, and lipids.
In this lesson you will learn what these molecules are made of, how to test for them in the laboratory, and how enzymes - the protein catalysts that run almost every reaction in your body - are affected by temperature and pH.
Objectives
- Identify the chemical elements present in carbohydrates, proteins and lipids (fats and oils)
- Describe the structure of carbohydrates, proteins and lipids as large molecules made up from smaller basic units: starch and glycogen from simple sugars, protein from amino acids, and lipid from fatty acids and glycerol
- Investigate food samples for the presence of glucose, starch, protein and fat
- Understand the role of enzymes as biological catalysts in metabolic reactions
- Understand how temperature changes can affect enzyme function, including changes to the shape of active site
- Investigate how enzyme activity can be affected by changes in temperature
- Understand how enzyme function can be affected by changes in pH altering the active site
Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Biological Molecules. Now that you've explored the key concepts and ideas, it's time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Which elements are found in proteins but NOT in carbohydrates? A) Carbon and hydrogen B) Nitrogen and sulfur C) Oxygen and hydrogen D) Carbon and oxygen Answer: B
- What is the positive result when Benedict's solution is added to glucose and heated? A) Blue to purple B) Brown-yellow to blue-black C) Blue to orange/brick-red D) Blue to green only Answer: C
- Enzymes are described as biological catalysts. What does 'catalyst' mean? A) A substance that is used up during a reaction B) A substance that slows down a chemical reaction C) A substance that speeds up a reaction without being used up D) A substance that provides energy for a reaction Answer: C
- What happens to an enzyme at temperatures much higher than its optimum? A) It works faster B) It becomes denatured C) It dissolves D) It changes into a different enzyme Answer: B
- Lipids are made from which basic units? A) Amino acids B) Simple sugars C) Fatty acids and glycerol D) Nucleotides Answer: C
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Further learning from open sources
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Textbook section
Enzymes
Describe the role of enzymes in metabolic pathways
"Biology: Enzymes" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/6-5-enzymes. Access for free at https://openstax.org/books/biology/pages/1-introduction
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Textbook section
Carbohydrates
Discuss the role of carbohydrates in cells and in the extracellular materials of animals and plants
"Biology: Carbohydrates" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/3-2-carbohydrates. Access for free at https://openstax.org/books/biology/pages/1-introduction
Published by other organisations under open licences, credited as they ask. Links open their websites.
Practice Mock Questions
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