Class 11 Biology Chapter 17 Locomotion and Movement – Revision Notes

Quick revision notes for Class 11 Biology Chapter 17 (Locomotion and Movement). These Class 11 Biology Chapter 17 notes are ideal for quick revision just before exams.

Movement Types

• Amoeboid, ciliary, muscular.

Muscle Types

• Skeletal (voluntary, striated), smooth (involuntary), cardiac (involuntary, striated).

Sliding Filament Theory

• Sarcomere; actin/myosin cross-bridges; requires Ca²⁺ + ATP; troponin/tropomyosin regulate.

Skeleton

• 206 bones: axial (80) + appendicular (126).
• Joints: fibrous (immovable), cartilaginous (slight), synovial (freely movable).

One-Line Summary

Locomotion and movement are enabled by the coordinated action of the skeletal and muscular systems, with muscle contraction driven by the ATP- and calcium-dependent sliding of actin and myosin filaments within sarcomeres.

Written by Satish

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