Ligaments, Tendons, Joints and Muscles (Leaving Cert Biology): Revision Notes

Ligaments, Tendons, Joints and Muscles

Ligaments

• Ligaments connect bone to bone and are made of strong, elastic fibres.
• They prevent the excessive movement of bones at a joint.
• Ligaments are more flexible when warm, so warming up before exercise helps prevent damage.

Tendons

• Tendons connect muscle to bone and are strong, flexible, inelastic fibres.
• They are composed of collagen and contain some blood vessels.

Joints

• A joint is where two or more bones meet.
• Joints are classified by the amount of movement they allow:

1. Immovable (Fixed or Fused) Joints

• Found in the skull and pelvic girdle.
• The junction between fused bones is called a suture**.**
• These joints provide strength, support, and protection.

2. Slightly Movable Joints

• Found between vertebrae in the upper spinal column.
• These joints are separated by pads of cartilage, which allow limited movement while providing cushioning and support.

3. Freely Moveable (Synovial)

• The ends of the bones are covered with cartilage and separated by a cavity.
• Bones are held in place by ligaments, which prevent excessive movement of bones at joints.
• Synovial fluid is found between the bones. This fluid lubricates the joint and reduces friction.
• Examples of synovial joints:
• Ball and socket joints (e.g., shoulder and hip).
• Hinged joints (e.g., elbow and knee).

Synovial Joint

Musculoskeletal Disorder: Arthritis

Cause

• Caused by swelling of the joints.
• Osteoarthritis is caused by wear and tear to cartilage in the joint. It usually affects one or a few joints.
• Rheumatoid arthritis is caused by the body's immune system attacking its own joints. It affects most joints in the body.

Prevention

• Osteoarthritis can be prevented by reducing wear and tear on joints.
• Use proper footwear and engage in non-impact exercise if a joint is sore or inflamed.

Treatment

• Arthritis is normally incurable.
• Treatment options:
• Rest.
• Weight loss.
• Special exercises to maintain agility.
• Anti-inflammatory medication.
• Surgery in severe cases to repair damage.

Muscles

• Muscles are adapted to contract.
• Muscles are made from protein.
• There are 3 types of muscle:

1. Involuntary (smooth): found in intestines, blood vessels and bladder.
2. Cardiac: found in the heart and does not tyre.
3. Voluntary (skeletal or striped): responsible for body movements and works in antagonistic pairs.

Antagonistic Pairs

• Antagonistic muscles are pairs of muscles that work opposite to each other e.g. biceps and triceps of the arm.
  • The biceps contract while the triceps relax, which raises the forearm.
  • The triceps contract while the biceps relax, which lowers the forearm.