Science for Grade 7
1 Introduction to Science
1-1 Definition of Science
1-2 Importance of Science in Daily Life
1-3 Scientific Method
1-3 1 Observation
1-3 2 Hypothesis
1-3 3 Experimentation
1-3 4 Analysis
1-3 5 Conclusion
2 Matter and Its Properties
2-1 States of Matter
2-1 1 Solid
2-1 2 Liquid
2-1 3 Gas
2-2 Properties of Matter
2-2 1 Mass
2-2 2 Volume
2-2 3 Density
2-2 4 Solubility
2-3 Changes in Matter
2-3 1 Physical Changes
2-3 2 Chemical Changes
2-4 Mixtures and Solutions
2-4 1 Types of Mixtures
2-4 2 Separation Techniques
3 Force and Motion
3-1 Types of Forces
3-1 1 Gravitational Force
3-1 2 Frictional Force
3-1 3 Magnetic Force
3-1 4 Electrostatic Force
3-2 Motion
3-2 1 Speed and Velocity
3-2 2 Acceleration
3-2 3 Newton's Laws of Motion
3-2 3-1 First Law (Inertia)
3-2 3-2 Second Law (Force and Acceleration)
3-2 3-3 Third Law (Action and Reaction)
4 Energy
4-1 Forms of Energy
4-1 1 Kinetic Energy
4-1 2 Potential Energy
4-1 3 Thermal Energy
4-1 4 Electrical Energy
4-1 5 Light Energy
4-1 6 Sound Energy
4-2 Energy Conversion
4-2 1 Mechanical to Electrical
4-2 2 Chemical to Thermal
4-2 3 Light to Electrical
4-3 Conservation of Energy
5 Heat and Temperature
5-1 Temperature
5-1 1 Measurement of Temperature
5-1 2 Temperature Scales
5-2 Heat Transfer
5-2 1 Conduction
5-2 2 Convection
5-2 3 Radiation
5-3 Effects of Heat
5-3 1 Expansion
5-3 2 Change of State
6 Light and Sound
6-1 Light
6-1 1 Sources of Light
6-1 2 Reflection
6-1 3 Refraction
6-1 4 Lenses and Mirrors
6-2 Sound
6-2 1 Production of Sound
6-2 2 Properties of Sound
6-2 3 Reflection of Sound
6-2 4 Applications of Sound
7 Earth and Space
7-1 Earth's Structure
7-1 1 Crust
7-1 2 Mantle
7-1 3 Core
7-2 Earth's Atmosphere
7-2 1 Layers of the Atmosphere
7-2 2 Weather and Climate
7-3 Solar System
7-3 1 Planets
7-3 2 Sun
7-3 3 Moon
7-4 Space Exploration
7-4 1 Rockets
7-4 2 Satellites
7-4 3 Space Stations
8 Living Organisms and Ecosystems
8-1 Classification of Living Organisms
8-1 1 Kingdoms
8-1 2 Species
8-2 Ecosystems
8-2 1 Components of an Ecosystem
8-2 2 Food Chains and Webs
8-3 Adaptations
8-3 1 Physical Adaptations
8-3 2 Behavioral Adaptations
8-4 Human Impact on Ecosystems
8-4 1 Pollution
8-4 2 Conservation Efforts
9 Health and Nutrition
9-1 Human Body Systems
9-1 1 Circulatory System
9-1 2 Respiratory System
9-1 3 Digestive System
9-1 4 Nervous System
9-2 Nutrition
9-2 1 Essential Nutrients
9-2 2 Balanced Diet
9-3 Diseases and Prevention
9-3 1 Infectious Diseases
9-3 2 Non-infectious Diseases
9-3 3 Hygiene and Prevention
10 Environmental Science
10-1 Natural Resources
10-1 1 Renewable Resources
10-1 2 Non-renewable Resources
10-2 Pollution
10-2 1 Air Pollution
10-2 2 Water Pollution
10-2 3 Soil Pollution
10-3 Sustainable Development
10-3 1 Importance of Sustainability
10-3 2 Sustainable Practices
10-4 Climate Change
10-4 1 Causes of Climate Change
10-4 2 Effects of Climate Change
10-4 3 Mitigation Strategies
9.1 Human Body Systems Explained

Understanding Human Body Systems

Key Concepts

1. Definition of Human Body Systems

Human body systems are groups of organs and tissues that work together to perform specific functions necessary for survival and well-being.

2. Major Human Body Systems

The major human body systems include the circulatory, respiratory, digestive, nervous, endocrine, musculoskeletal, immune, excretory, and reproductive systems.

3. Circulatory System

The circulatory system, also known as the cardiovascular system, is responsible for transporting blood, nutrients, oxygen, and waste products throughout the body.

4. Respiratory System

The respiratory system is responsible for taking in oxygen and releasing carbon dioxide, enabling cellular respiration and energy production.

5. Digestive System

The digestive system breaks down food into smaller molecules that can be absorbed and used by the body for energy, growth, and cell repair.

6. Nervous System

The nervous system controls and coordinates body activities by transmitting signals between different parts of the body and the brain.

7. Endocrine System

The endocrine system regulates various bodily functions through the secretion of hormones, which are chemical messengers.

8. Musculoskeletal System

The musculoskeletal system provides support, stability, and movement to the body through bones, muscles, and joints.

9. Immune System

The immune system protects the body against infections and diseases by identifying and destroying harmful pathogens.

10. Excretory System

The excretory system removes waste products from the body, including excess water, salts, and metabolic byproducts.

11. Reproductive System

The reproductive system is responsible for the production of offspring and the continuation of the species.

Explanation of Each Concept

1. Definition of Human Body Systems

Human body systems are interconnected groups of organs and tissues that work together to perform specific functions necessary for survival and well-being.

2. Major Human Body Systems

The major human body systems include the circulatory, respiratory, digestive, nervous, endocrine, musculoskeletal, immune, excretory, and reproductive systems. Each system has a unique role in maintaining overall health and function.

3. Circulatory System

The circulatory system, consisting of the heart, blood vessels, and blood, transports oxygen, nutrients, and waste products throughout the body. The heart pumps blood to all parts of the body, ensuring that cells receive the necessary nutrients and oxygen.

4. Respiratory System

The respiratory system, including the lungs and airways, facilitates the exchange of oxygen and carbon dioxide. Oxygen is inhaled into the lungs, where it diffuses into the bloodstream, while carbon dioxide is exhaled as a waste product.

5. Digestive System

The digestive system, comprising the mouth, esophagus, stomach, intestines, and other organs, breaks down food into smaller molecules that can be absorbed and used by the body. This process provides energy and essential nutrients for growth and repair.

6. Nervous System

The nervous system, including the brain, spinal cord, and nerves, controls and coordinates body activities by transmitting signals between different parts of the body and the brain. It enables rapid responses to stimuli and maintains homeostasis.

7. Endocrine System

The endocrine system, consisting of glands that secrete hormones, regulates various bodily functions such as growth, metabolism, and reproduction. Hormones are chemical messengers that travel through the bloodstream to target organs and tissues.

8. Musculoskeletal System

The musculoskeletal system, including bones, muscles, and joints, provides support, stability, and movement to the body. Bones form the skeleton, muscles attach to bones and generate movement, and joints allow for flexibility and range of motion.

9. Immune System

The immune system, comprising white blood cells, antibodies, and other components, protects the body against infections and diseases. It identifies and destroys harmful pathogens, such as bacteria and viruses, to maintain health.

10. Excretory System

The excretory system, including the kidneys, bladder, and urinary tract, removes waste products from the body. The kidneys filter blood to remove excess water, salts, and metabolic byproducts, which are then excreted as urine.

11. Reproductive System

The reproductive system, consisting of organs and tissues in both males and females, is responsible for the production of offspring. In males, the testes produce sperm, while in females, the ovaries produce eggs. The system also supports the development of a fetus during pregnancy.

Examples and Analogies

Example 1: Circulatory System

Think of the circulatory system as a transportation network. The heart is like a pump station, blood vessels are the roads, and blood is the vehicle that carries essential supplies (oxygen and nutrients) to different parts of the body.

Example 2: Respiratory System

Imagine the respiratory system as a ventilation system. The lungs are like air filters that take in fresh air (oxygen) and release stale air (carbon dioxide) to maintain a healthy environment inside the body.

Analogy: Digestive System

Think of the digestive system as a food processing factory. Food enters the mouth (like raw materials), goes through various stages (like different machines), and comes out as usable energy and nutrients (like finished products).