Biology 107

Lecture Notes: Movement and Locomotion.

Reading: Chapter 49, Pages 1075-1086 in text.

Movement and Locomotion

• Skeletons support and protect the body and are essential for movement

• Types of skeletons

• Hydrostatic skeleton

• Exoskeleton

• Endoskeleton

• Muscles move skeletal parts by contracting

• Structure and function of vertebrate skeletal muscle

• Thin filaments

• Thick filaments

• Sarcomere

• Z lines

• I bands

• A bands

• H zones

• Interactions between myosin and actin underlie muscle contractions

• the sliding filament model

• rigor

• Calcium ions and regulatory proteins control muscle contraction

• Skeletal muscles contract when stimulated by motor neurons

• Tropomyosin

• troponin complex

• transverse or T tubules

• sarcoplasmic reticulum

• Muscle is remodeled to match function

• Diverse body movements require variation in muscle activity

• Recruitment

• motor unit

• Fast and slow muscle fibers

• Other types of muscles

• Cardiac muscle

• Smooth muscle

• Invertebrates have muscles similar to the skeletal and smooth muscles of vertebrates, but with some interesting adaptations