F2 IS QZ 05 anwers

Marks: =       /29 =    %

1st Term QZ 04 05 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

7.3

Word Translation (6 marks)

i    Write down the English terms of the following Chinese terms:

	Chinese term	English term
1	化學能	Chemical energy
2	能量值	Energy content
3	千卡路里	Kilocalories
4	千焦耳	Kilojoules
5	過重	Overweight
6	呼吸作用	Respiration

Fill in the Blanks (23 marks)

1      We need energy to carry out various activities. Energy is also needed for maintaining our body temperature, heartbeat and breathing. Such energy comes from the food we eat.

2      In our body, the chemical energy stored in food is released by a complex chemical process called respiration which takes place in our living cells. In this chemical process, food reacts with oxygen to form carbon dioxide and water. The energy released is used to support our body activities.

        The WORD equation of this process is as follows:

        Food + oxygen ---------------------------à energy + carbon dioxide + water

                                   Living cells                                                                       

5      In both burning and respiration, oxygen is consumed, carbon dioxide and water are produced. However, Energy is released faster in burning than in respiration.

6      The amounts of energy that the foods can provide are called the       energy contents.

It is measured in kilojoules (kJ) or kilocalories (kcal).

7      Eating too much high-energy food can make us become overweight.

Challenging Questions (Bonus 2 marks)

State TWO differences between respiration and burning.

Any TWO of the following:

A flame exists in burning but not in respiration. /

Respiration is a much complicated process than burning. /

Respiration occurs in living cells while burning takes place in air. /

The energy is released much slower in respiration than burning.