The Muscular System

Muscles Bones require muscles for locomotion Muscles move bone by contracting (shortening)

Function of Muscles Produce movement Maintain posture Stabilize joints Generate heat

The Muscular System Muscles are responsible for all types of body movement – they contract or shorten and are the machine of the body Three basic muscle types are found in the body Smooth muscle Cardiac muscle Skeletal muscle

There are three types of Muscle: Smooth Muscle Located in the digestive and reproductive system Under Involuntary control Cardiac Muscle Found in the wall of the heart under Involuntary control Skeletal Muscle Attached to bone Provide force for moving and stabilizing the body Under Voluntary control Striated muscle

4 Types of Connective Tissue At the joints (where bones meet), there are different types of connective tissue: Ligament – connects bone to bone Tendon – connects muscle to bone Bursa – fluid filled sac that allows bones to move easily over others Cartilage – connective tissue that cushions the joint at the end of bones and between bones

Anatomy of the Muscular System Origin Muscle attachment that remains fixed Insertion Muscle attachment that moves Action What joint movement a muscle produces i.e. flexion, extension, abduction, etc.

For muscles to create a movement, they can only pull, not push Muscles in the body rarely work alone, & are usually arranged in groups surrounding a joint A muscle that contracts to create the desired action is known as an agonist or prime mover A muscle that helps the agonist is a synergist A muscle that opposes the action of the agonist, therefore undoing the desired action is an antagonist

Antagonistic Muscles A pair of muscles which work against each other to make a joint move The muscle that contracts to bend the joint is the flexor, and the muscle that contracts to straighten the joint is the extensor

Did you know… If you’re double jointed it means that you have extra stretchy ligaments which allows your joints more flexibility

Movement Muscles move bones. Muscles are attached to the bone by tendons. When the muscle contracts, it becomes shorter and pulls the tendon which pulls the bone. When the muscle relaxes, the pulling stops. Muscles can only PULL, so they work in pairs. For example, the bicep contracts to pull the lower arm up. When the tricep contracts, your arm straightens.

Summary Bones provide the framework of the body, joints allow for movement, and muscles provide the strength to realize the movements. The kind of movement depends on the shape of the bone and in the joint.

MUSCLES YOU NEED TO KNOW! frontalis gracilis orbicularis oculi vastus medialis orbicularis oris gastrocnemius sternocleidomastoid soleus deltoid trapezius pectoralis major teres major biceps brachii triceps brachii brachialis latissimus dorsi rectus abdominis external oblique brachoradialis gluteus medius pronator teres gluteus maximus flexor carpi radialis semimembranosis iliopsoas semitendinosis Sartorius Achilles tendon vastus lateralis pectineus biceps femoris rectus femoris extensor carpi ulnaris peroneus longus flexor carpi ulnaris tibialis anterior

An Overview of the Major Skeletal Muscles

An Overview of the Major Skeletal Muscles Figure 7-11(b)

Anatomy of the Muscular System Muscles of the Head and Neck Figure 7-12(a)

Anatomy of the Muscular System Muscles of the Head and Neck Figure 7-12(c)

Anatomy of the Muscular System Muscles of the Anterior Neck Figure 7-13

Anatomy of the Muscular System Muscles of the Spine Figure 7-14

Anatomy of the Muscular System Muscles of the Shoulder Figure 7-17(a)

Anatomy of the Muscular System Muscles of the Shoulder Figure 7-17(b)

Anatomy of the Muscular System Muscles that Move the Arm Figure 7-18(a)

Anatomy of the Muscular System Muscles That Move the Forearm and Wrist Figure 7-19

Anatomy of the Muscular System Muscles That Move the Thigh Figure 7-20(a)

Anatomy of the Muscular System Muscles That Move the Thigh Figure 7-20(b)

Anatomy of the Muscular System Muscles That Move the Leg Figure 7-21

Anatomy of the Muscular System Muscles That Move the Foot and Toes Figure 7-22(a)

Anatomy of the Muscular System Muscles That Move the Foot and Toes Figure 7-22(b)

Anatomy of the Muscular System Muscles That Move the Foot and Toes Figure 7-22(c)

Anatomy of the Muscular System Muscles That Move the Foot and Toes Figure 7-22(d)