OUR OWN ENGLISH HIGH SCHOOL, DUBAI2012-2013

GRADE:7 TOPIC NAME : Respiration in organisms (PRACTICE SHEET/ADVANCED) DATE:3.6.12

A. FILL IN THE BLANKS

1. Roots obtain air from --------------------------------------------------- in the soil.

2. ------------------------------------------------------- is the substance oxidized during respiration.

3. In unicellular animals, the exchange of gases happens by--------------------------------.

4. Cellular respiration that uses oxygen is called------------------------------------------------ respiration. If it occurs without oxygen, the process is called------------------------------------------------------.

5. Many micro-organisms such as yeast, bacteria, and fungi can respire only------------------------------------.-

B. State whether true or false.

1. The size of the chest cavity increases during inhalation.

2. Frogs breathe with the help of lungs.

3. In insects, oxygen is taken to all parts of the body through blood.

4.An athlete suffers from cramps; due to the accumulation of lactic acid in the muscles

5. Oxygen combines with hemoglobin to form oxyhaemoglobin.

C. Short answer questions. (not more than 20 words)

1. How do earthworms breathe?

2. Represent the process of respiration using an equation.

3. When does anaerobic respiration occur in the human body?

4. Stomata are closed at night. How do plants breathe at night?

5. What is an alveolus?

D. Hots (questions)

1. Why do plants not need a respiratory system?

2. A person put warm water in an aquarium, thinking that the fish would be more comfortable in it.(However, the fish died what can be the reason for this?)

3. Why do you think we yawn when we are sleepy or drowsy?

4. Is it wise to sleep under a tree (a) during the day (b) at night? Give reason.

5. Why do mountaineers climbing high mountains carry oxygen cylinders with them?

E. Match the following.

A

Respiratory system1Two air tubes

BAlveoli

2Moves from the air into the capillaries

CCapillaries

3Made of two lungs

F. Place the correct letter for each of the following characteristics in the appropriate box given in the diagram.

a) Site of gas exchange b) Major organ of the respiratory system.

c) Filters warms and moistens air d) Used for inhalation and exhalation

e) Allows food and air to pass through f) Sound production.

G. Compare the blood in blood vessel X to blood vessel Y