Page 92 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

7. Explain the mechanism of breathing in humans.

Ans. Breathing in humans is a process that involves inhalation and exhalation.

During inhalation the diaphragm, contracts & moves downwards, while the rib
muscles lift the rib cage up & out. This expands the chest cavity, causing air to rush

into the lungs.

During exhalation, the diaphragm & rib muscles relax, allowing the lungs to contract

& push air out of the lungs.

This movement of air facilitates the exchange of gases, bringing oxygen into the body
for energy production & removing carbon dioxide as a waste product.

8. Differentiate between breathing and cellular respiration.
Ans. Breathing Cellular Respiration

It is a physical process. It is a biochemical process.
It occurs in the lungs. It occurs in the cells.

Energy is consumed during the process. Energy is released in the form of ATP.
No enzymes are used during the process. A large number of enzymes are used

during the process.
It is an extracellular process. It is an intracellular process.

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