Available Answers

1. 1.

   Fill in the blanks.

   1. The ribs move __________ during exhalation.
   2. Cramps in muscles occur due to accumulation of __________.
   3. The size of the chest cavity __________ during inhalation.
   4. Breathing rate __________ during heavy exercise.
   5. The inhaled air is filtered by hairs and sticky fluid inside the __________.
2. 2.

   Write T for the true and F for the false statements.

   1. The tadpoles breathe through gills.
   2. Photosynthesis occurs during day and respiration occurs during night in plants.
   3. Energy and oxygen are released during the process of respiration.
   4. Increased physical activity enhances the rate of breathing.
   5. In old trees, exchange of gases occurs through lenticels.
3. 3.

   Give one word for the following:

   1. intake of oxygen during breathing
   2. organisms need oxygen for respiration
   3. number of breaths per minute
   4. a large dome-shaped muscular sheet lies in the chest cavity
   5. small openings found in insects for the entry of air
4. 4.

   Match the columns.

   A	B
   1. Yeast	a. Lungs and skin
   2. Frog	b. Stomata
   3. Leaves	c. Spiracles
   4. Flies	d. Gills
   5. Fish	e. Alcohol

    

5. 5.

   How do plants respire?

6. 6.

   Arrange the organs of respiratory system of human being in the order the air passes through these organs.

   trachea, nasal cavity, nostrils, larynx, lungs, pharynx