F2 1st Term IS WS 12 Answers

7.6       Breathing and breathing system

             in humans

C. Our breathing mechanism

i      Words to know:

	English term	Write the words again	Chinese term
1	Diaphragm		橫膈膜
2	Intercostal muscle		肋間肌
3	Rib		肋骨
4	Chest		胸腔
5	Volume		體積
6	Pressure		壓力
7	Contract / Relax		收縮 / 放鬆
8	Upwards / Downwards		向上 / 向下
9	Inwards / Outwards		向內 / 向外

i      Fill in the blanks:

1       Breathing is brought about by the actions of diaphragm / intercostal muscles, the ribs and the Intercostal muscles / diaphragm.

2       Breathing involves changes in volume and pressure inside the chest.

3       Fill in the table to show how our body works on breathing.

	Breathing in	Breathing out
Diaphragm	move upwards / downwards	Move upwards
Intercostal muscles	contract	contract / relax
Ribs move	Upwards / downwards and outwards / inwards	Downwards and inwards
Volume inside the chest	increases	increases / decreases
Gas pressure inside the chest	increases / decreases	increases
Air flows	Into the lungs	Into / out of the lungs

i      Writing:

1      During the process of breathing in, the diaphragm becomes flat. The intercostal         muscles contract, causing the ribs to move upwards and outwards. The volume inside the chest increases, and the gas pressure inside decreases. Thus air flows into the lungs.

         the lungs.

2      When we breathe out, the diaphragm moves upwards. The intercostal muscles relax, causing the ribs to move downwards and inwards. The volume inside the chest decreases, and the gas pressure inside increases. Thus, air flows out of the lungs.

F2 1st Term IS WS 11 Answers

7.6       Breathing and breathing system

             in humans

A.     The importance of breathing

B.      Our breathing system

i      Words to know:

	English term	Write the words again	Chinese term
1	Respiration		呼吸作用
2	Gaseous exchange		氣體交換
3	Breathing		呼吸
4	Breathing system		呼吸系統
5	Lung		肺
6	Intercostal muscle		肋間肌
7	Diaphragm		橫膈膜
8	Rib		肋骨
9	Bronchus		支氣管
10	Trachea		氣管
11	Air sac		氣囊 / 肺泡

i      Matching:

Breathing	•Drawing of air in and out of the lungs
Gaseous exchange	•Exchange of oxygen and carbon dioxide between the air and the blood  inside lungs
Respiration	•Complicated chemical process which release energy from food

i      Fill in the blanks:

1       Our living cells need continuous supply of oxygen for use in respiration for releasing energy.

2       Breathing is a process by which air is repeatedly drawn into and out of the lungs.

3       Through gaseous exchange in our lungs, we obtain oxygen from the environment and release carbon dioxide to the environment. Oxygen in the air enters the blood while carbon dioxide leaves the blood and goes into the air.

4       In the human body, there is a well-developed breathing system that facilitates gaseous exchange. Lung is the part of this system in which gaseous exchange occurs.

5       Sequence (次序) of structures through which air enters the breathing system:

         Air à Nose à Trachea à Bronchi à small tubes à Air sacs

                     or mouth

6        Label the following diagrams:

7       In the air sacs, oxygen enters the blood (air / blood) from the air

while carbon dioxide leaves the blood and goes into the air.

8       The following table shows the difference between the blood entering and leaving the air sacs:

	Blood entering air sacs	Blood leaving the air sacs
Come from	Living cells / air sacs	Air sacs
Go to	Air sacs	Living cells
Oxygen content	Higher / Lower	Higher
Carbon dioxide content	Higher	Lower