TOPIC 1C - DIET AND HEALTH

Question 1

Why do organisms need a supply of energy?

Answer 1

So they can grow, move, reproduce etc — in animals this energy is provided in the form of food

Question 2

What is the energy budget?

Answer 2

Term used to describe the amount of energy taken in by an organism (in food) and the amount of energy used up by an organism (e.g. by moving)

Question 3

What causes changes in weight?

Answer 3

Energy imbalance. Ideally a person should take in the same amount of energy as they use up — energy budget should be balanced

Question 4

What causes weight gain?

Answer 4

If energy intake is higher than energy output, the excess energy will be turnes into fat reserves by the body, so the person will gain weight. If the energy difference is a lot and it’s sustained over a long period of time, the person could become obese

Question 5

What causes weight loss?

Answer 5

If energy intake is lower than energy output, the body will have to get more energy from somewhere — it’ll turn some of it’s fat reserves into energy, so the person will loose weight. If this energy difference is large and sustained over a long period of time, the person is likely to become underweight.

Question 6

How do you calculate a person energy budgets?

Answer 6

Energy input - Energy Output = Energy Budget

Question 7

How can you measure the amount of Vitamin C in your food?

Answer 7

1. Make up several vitamin C solutions of different, known concentrations. Ideally, six different solutions.
2. Use a measuring cylinder to measure out a set volume of DCPIP (at a set concentration) into a test tube.
3. Add one of the vitamin C solutions to the DCPIP, drop by drop, using a Pipette.
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