Skeletal System enote

📘 BASIC SCIENCE E-NOTE

Topic: Skeletal System

👉 Meaning of Skeletal System

• The skeletal system is the framework of bones that gives the body shape, support, protection, and allows movement.

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👉 Bones and Their Functions

• Bones are hard structures that make up the skeleton.
• Functions of bones:
1. Support the body.
2. Protect delicate organs (skull → brain, ribs → heart/lungs).
3. Help movement (with muscles and joints).
4. Produce blood cells (in bone marrow).
5. Store minerals (calcium and phosphorus).

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👉 The Skeleton (Parts and Functions)

1. Skull → protects the brain.
2. Rib cage → protects heart and lungs.
3. Vertebral column (backbone) → supports the body and allows bending.
4. Limbs (arms and legs) → help in movement and work.

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👉 Joints and Types of Joints

• A joint is the place where two or more bones meet.
• Types of joints:
1. Fixed joint → no movement (skull).
2. Hinge joint → movement in one direction (elbow, knee).
3. Ball and socket joint → movement in many directions (shoulder, hip).
4. Pivot joint → turning movement (neck).
5. Gliding joint → sliding movement (wrist, ankle).

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👉 Muscles (Types and Functions)

• Muscles are tissues that contract and relax to produce movement.
• Types of muscles:
1. Skeletal muscles → voluntary (arms, legs).
2. Smooth muscles → involuntary (stomach, intestines).
3. Cardiac muscles → found in the heart, work continuously.

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👉 Movement and Its Importance

• Movement allows us to carry out daily activities (walking, writing, sports).
• It keeps the body fit and healthy.
• Prevents stiffness and improves blood circulation.

ASSIGNMENT

1. What is the skeletal system?
2. Mention two functions of bones.
3. State two parts of the skeleton and their functions.
4. List two types of joints and examples.
5. Name three types of muscles and where they are found.
6. State two reasons why movement is important.