Diffusion

Q.

Name the tiny pores present in the leaves of plants for exchange of gases.

1. Tracheae

2. Spiracles

3. Stomata

4. Chloroplast

Q. Plants also show movement. Justify the statement.

Q.

The movement of substances from a region of higher concentration to a region of lower concentration is called :

1. Diffusion

2. Cellular respiration

3. Both a and b

4. Osmosis

Q. Name the four whorls of flowers.

Q.

Why is a cell membrane thin?

Q.

Plants do not die even in bright scorching sunlight. Why?

Q.

Which side of the dicot leaf transpires more water in the form of vapor?

Q.

The figure shown above shows a simple diagram of gas exchange occurring in the between the alveolus of the lung and the blood. If gas A goes “out” and gas B goes “ in” with respect to the blood as shown in the diagram, identify gases A and B.

1. A – water, B- carbon dioxide

2. A – carbon dioxide, B- nitrogen

3. A –carbon dioxide, B- oxygen

4. A – oxygen, B- carbon dioxide

Q.

Why do mountaineers carry oxygen with them?

1. There is no air above 5 km.

2. The pressure of air is higher than that on ground.

3. The temperature of air is higher than that on ground.

4. The amount of air available on mountains is less.

Q.

Which of the following is true about the exchange of gases in the lungs?

1. The concentration of carbon dioxide is higher in air

2. The concentration of carbon dioxide is higher in blood

3. Nothing can be said about the concentration of carbon dioxide

4. The concentration of carbon dioxide is the same in blood and air

Q. A complete flower has ___ whorls.

Q. Which among the following organisms will be most affected if the dissolved oxygen in water is reduced?

1. Dolphins
2. Whales
3. Frogs
4. Fishes

Q. Which of the following is not true regarding alveoli?

1. It is a single-celled sac of air
2. It is a multi-celled sac of air
3. It has thin walls
4. It facilitates the exchange of oxygen and carbon dioxide molecules into or away from the bloodstream.

Q. Exchange of gases occurs at across the alveolar membrane by

1. Osmosis
2. Transpiration
3. Diffusion
4. Osmoregulation

Q. Name the four whorls of flowers.

Q.

Odour spreads from one room to another by the process of:

1. Separation

2. Osmosis

3. Expansion

4. Diffusion

Q. Write any 2 functions of cell membrane.

Q. Which among the following organisms will be most affected if the dissolved oxygen in water is reduced?

Q. Exchange of gases occurs at across the alveolar membrane by

1. Osmoregulation
2. Osmosis
3. Transpiration
4. Diffusion

Q. Which among the following organisms will be most affected if the dissolved oxygen in water is reduced?

1. Frogs
2. Whales
3. Fishes
4. Dolphins

Q.

Which term refers to the movement of molecules from an area of higher concentration to an area of lower concentration?

1. active transport

2. diffusion

3. concentration

4. collision

Q. Oxygen is used to breakdown glucose outside the cells of organisms.

1. True
2. False

Q. What is the function of the cell membrane?

1. To perform different functions in each cell
2. To control what enters and leaves the cell
3. To form a hard outer covering for the cell
4. To support the cell

Q. A complete flower has ___ whorls.

1. 5
2. 4
3. 3
4. 6