Revision Kit: Rapid Recall

1. The Joints Jargon

  • Atlas & Axis: Pivot Joint (Rotation - shaking head "no").
  • Thumb (Carpal-Metacarpal): Saddle Joint (Unique opposition).
  • Knee/Elbow: Hinge Joint (Door-like movement).
  • Shoulder/Hip: Ball and Socket (Maximum mobility).
  • Skull Sutures: Fibrous Joint (Immovable).

2. Muscle Mechanism Shortcuts

  • Contraction Trigger: Calcium (Ca++Ca^{++}) binds to Troponin →\rightarrow Active sites unmasked.
  • A-Band: Length remains constant (Thick myosin never shrinks!).
  • I-Band & H-Zone: Shorten/Disappear during contraction.
  • Red Fibres: High Myoglobin + Mitochondria = Aerobic (Endurance runners).
  • White Fibres: Low Myoglobin = Anaerobic (Sprinters).

Skeletal Stats (Know Your Numbers!)

  • Facial Bones: 14.
  • Cranial Bones: 8.
  • Ribs: 1-7 (True), 8-10 (Vertebrochondral/False), 11-12 (Floating).
  • Vertebrae Formula: 7-12-5-1-1 (C-T-L-S-Co).
  • Limb Bones: Exactly 30 per limb.

4. Disorder Keywords

  • Myasthenia Gravis: Autoimmune, hits the Neuromuscular Junction (NMJ), causes extreme fatigue.
  • Tetany: Low Calcium (Ca++Ca^{++}), wild spasms.
  • Gout: Uric acid crystals in joints.
  • Osteoporosis: Low Estrogen (post-menopause), porous bone loss.