i. In cockroaches, air enters the body through spiracles.
ii. During heavy exercise, we get cramps in the legs due to the accumulation of lactic acid.
iii. Normal range of breathing rate per minute in an average adult person at rest is 15ñ18.
iv. During exhalation, the ribs move downwards.
v. Breathing is a part of the process of respiration.
i. During heavy exercise the breathing rate of a person slows down. False
ii. Gills are well supplied with blood vessels for exchange of gases. True
iii. Plants carry out photosynthesis only during the day and respiration only at night. False
iv. Frogs breathe through their skins as well as their lungs. True
v. The fishes have lungs for respiration. False
vi. The size of the chest cavity increases during inhalation. True
Ans. Some common uses of Yeast are bread, wine and beer.
Ans. Yeast can survive in the absence of air.
Ans. Earthworms breathe through their skins.
Ans. A breath means one inhalation plus one exhalation.
Ans. A cell is the smallest structural and functional unit of an organism.
Ans. All organisms are made of small microscopic units called cells.
Ans. They have lungs in their chest cavities like the human beings.
Ans. A large, muscular sheet called diaphragm forms the floor of the chest cavity.
Ans. The end products of anaerobic respiration are alcohol, carbon dioxide and energy.
Ans. Lactic acid is produced during anaerobic respiration in muscles that causes cramps.
Ans. The process of breakdown of food in the cell with the release of energy is called cellular respiration.
Ans. The number of times a person breathes in a minute is termed as the breathing rate.
Ans. Smoking damages lungs. Smoking is also linked to cancer. So, it must be avoided.
Ans. Insects have small openings on their body that allow them to breathe. These openings are called spiracles.
Ans. We should eat regularly because food has stored energy, which is released during respiration.
Ans. Leaves of the plants have tiny pores called stomata for exchange of oxygen and carbon dioxide.
Ans. Breathing means taking in air rich in oxygen and giving out air rich in carbon dioxide with the help of respiratory organs.
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