Class 7 Science

Chapter 10: Respiration in Organisms

STAGE 0: Foundation / Basics

All living organisms need energy to live.

The process of releasing energy from food is called respiration.

What is Respiration?

Respiration is the process by which food is broken down to release energy.

Oxygen is used in respiration and carbon dioxide is released.

Types of Respiration

1. Aerobic Respiration:

• Takes place in the presence of oxygen
• Releases more energy
• Example: Humans

2. Anaerobic Respiration:

• Takes place without oxygen
• Releases less energy
• Example: Yeast

Respiration in Humans

Humans breathe through the nose.

Main organs involved:

• Nose
• Windpipe (Trachea)
• Lungs

Lungs contain tiny air sacs called alveoli.

Respiration in Other Organisms

• Fish – gills
• Earthworm – skin
• Insects – spiracles
• Plants – stomata

Breathing

Breathing is the process of taking in oxygen and giving out carbon dioxide.

Breathing is different from respiration.

STAGE 2: NCERT Textbook Questions & Answers

Q1. What is respiration?

Respiration is the process of releasing energy from food.

Q2. Name the two types of respiration.

Aerobic and Anaerobic respiration

Q3. Which organs help in breathing in humans?

Nose, windpipe, and lungs

STAGE 3: Exam-Oriented Questions

Fill in the blanks:

• Respiration releases __________ from food.
• Fish breathe through __________.

Very Short Answer:

Name the breathing organ in insects.
Answer: Spiracles

Quick Revision Points

• Respiration releases energy
• Oxygen is needed for aerobic respiration
• Humans breathe through lungs
• Different organisms have different breathing organs