Biology (9-1) - 0970 CIE

Diet

Overview

You are what you eat, quite literally: the food in your diet supplies the energy and raw materials to build every cell. But it is not enough to eat plenty; you need the right balance of seven different nutrients. Miss out on just one, such as vitamin C or vitamin D, and a deficiency disease follows.

In this lesson you will learn what a balanced diet is, the dietary sources and importance of each nutrient (carbohydrates, fats, proteins, vitamins C and D, the mineral ions calcium and iron, fibre and water), and the causes of two classic deficiency diseases, scurvy and rickets.

Objectives

  1. Describe what is meant by a balanced diet
  2. State the principal dietary sources and describe the importance of: (a) carbohydrates (b) fats and oils (c) proteins (d) vitamins, limited to C and D (e) mineral ions, limited to calcium and iron (f) fibre (roughage) (g) water
  3. State the causes of scurvy and rickets

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Flashcards

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Lesson Note

Diet links the chemistry of food molecules to human health. Examiners ask for the components of a balanced diet, the job and a food source of each nutrient, and the causes of scurvy and rickets. These are precise, learnable facts that reliably appear, and they connect to digestion, blood and bones elsewhere in the course.

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Lesson Evaluation

Congratulations on completing the lesson on Diet. Now that youve explored the key concepts and ideas, its 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.

  1. Which nutrient is needed mainly for growth and repair of tissues? A. carbohydrate B. fat C. protein D. fibre Answer: C
  2. A lack of vitamin C causes: A. rickets B. scurvy C. anaemia D. constipation Answer: B
  3. Iron is needed in the diet to make: A. bones B. haemoglobin C. enzymes D. cellulose Answer: B
  4. Which mineral ion makes bones and teeth hard? A. iron B. calcium C. nitrate D. magnesium Answer: B
  5. Rickets in children is caused by a lack of: A. vitamin C B. vitamin D C. fibre D. protein Answer: B

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