Quickwrite What do you think is the strongest muscle in the body?

The Muscular System 32.3

What are the Types of Muscle Involuntary Muscle – Smooth Muscle – Cardiac Muscle Voluntary Muscle – Skeletal Muscle Tendons

How do Muscles Contract Muscles arranged into fibers Each fiber made up of a myofibril Each myofibril is composed of actin and myosin Calcium is released into sarcomere which activates actin and myosin Antagonistic contractions

What is the Sliding Filament Theory Leading theory of how muscles contract Actin binds to myosin and pulls actin along Sarcomere is the functional unit of muscle that contracts The whole muscle does not contract at once

How do Muscles Get Energy ATP is required for muscle contraction Muscles undergo aerobic or anaerobic respiration – Muscle soreness comes from lactic acid build up

Slow Twitch vs Fast Twitch Muscles Slow twitch muscles are used for endurance – Have multiple mitochondria for prolonged exercise Fast twitch muscles are for short bursts of energy – Have fewer mitochondria than slow twitch (aerobic or anaerobic respiration?) Most muscles have a mixture of both What kind of turkey meat is fast twitch/slow twitch (light or dark meat)

Activity With a partner, research botulism or tetanus. Write a paragraph explaining how it affects the body and why it affects the muscular system. Draw and color a picture of how the body would look when it is affected by your disorder. On your picture, label where you would find the following muscles: biceps brachii, triceps brachii, pectoralis major, quadriceps, rectus abominus, deltoid