The Muscular System

Defn: Is a tough group of tissues that make your body parts move. Defn: Is a tough group of tissues that make your body parts move. Fact: You have over 650 major muscles in the body and they work the same way. Over 50 of those muscles are in your face alone. It takes 17 muscles to smile and over 40 to frown. Fact: You have over 650 major muscles in the body and they work the same way. Over 50 of those muscles are in your face alone. It takes 17 muscles to smile and over 40 to frown. The strongest muscle in your body is the masseter muscle, located on each side of the mouth. The strongest muscle in your body is the masseter muscle, located on each side of the mouth. Your most active muscles are those in your eyes. They move more than 100,000 times a day. Your most active muscles are those in your eyes. They move more than 100,000 times a day.

Muscles Work in Pairs They work in Pairs either contracting (shortening) or extending (lengthening). They work in Pairs either contracting (shortening) or extending (lengthening). –Ex. Bicep contracts while Triceps extend

Views of the Body Anterior View Posterior View

Functions of Muscle: Movement Skeletal muscles Skeletal muscles –Attached to bones by tendons –Cross joints so when they contract, bones they attach to move Smooth muscle Smooth muscle –Found on organ walls –Contractions produce movement of organ contents Cardiac muscle Cardiac muscle –Produces atrial and ventricular contractions –This pumps blood from the heart into the blood vessels

Three Types of Muscle Three Types of Muscle Smooth Muscles: Are found in various organs in the body, such as the stomach and the intestines. You have no control over these muscles. Contractions produce movement of organ contents Smooth Muscles: Are found in various organs in the body, such as the stomach and the intestines. You have no control over these muscles. Contractions produce movement of organ contents

Three Types of Muscle Skeletal Muscle: These muscles are attached to a bone, which allows the skeleton to move. For example you can make your arms and legs move whenever you want to. Skeletal Muscle: These muscles are attached to a bone, which allows the skeleton to move. For example you can make your arms and legs move whenever you want to.

Three Types of Muscles Cardiac Muscle: Only found in the walls of the heart. Cardiac muscles are constantly contracting and relaxing, pumping blood to all parts of the body. Cardiac Muscle: Only found in the walls of the heart. Cardiac muscles are constantly contracting and relaxing, pumping blood to all parts of the body.

Three Types of Human Muscle Tissue Skeletal Cardiac Smooth

Three Types of Muscles

Types of Muscle Movement Involuntary – You cannot control Involuntary – You cannot control –Smooth Muscle Voluntary- You Control Voluntary- You Control –Striated Muscle

Functions of Muscle: Stability Hold bones tightly together Hold bones tightly together –Stabilize joints Small muscles hold vertebrae together Small muscles hold vertebrae together –Stabilize the spinal column

Functions of Muscle: Control of Body Openings and Passages Sphincters Sphincters –Valve-like structures formed by muscles –Control movement of substances in and out of passages –Example:  A urethral sphincter prevents or allows urination

Functions of Muscle: Heat Production Heat is released with muscle contraction Heat is released with muscle contraction –Helps the body maintain a normal temperature –Moving your body can make you warmer if you are cold

Types of Muscle Tissue Muscle cells Muscle cells –Myocytes called muscle fibers –Sarcolemma – cell membrane –Sarcoplasm – cytoplasm of cell –Myofibrils – long structures in sarcoplasm  Arrangement of filaments in myofibrils produces striations

Attachments and Actions: Body Movements Flexion – bending a body part Extension – straightening a body part Hyperextension – extending a body part past the normal anatomical position Dorsiflexion – pointing the toes up Plantar flexion – pointing the toes down Abduction – moving a body part away from the anatomical position Adduction – moving a body part toward the anatomical position

Circumduction – moving a body part in a circle Pronation – turning the palm of the hand down Supination – turning the palm of the hand up Inversion – turning the sole of the foot medially Eversion – turning the sole of the foot laterally Retraction – moving a body part posteriorly Protraction – moving a body part anteriorly Attachments and Actions: Body Movements (cont.)

Elevation – lifting a body part; for example, elevating the shoulders as in a shrugging expression Depression – lowering a body part; for example, lowering the shoulders Attachments and Actions: Body Movements (cont.)

Human Muscular System Diagram Deltoid Pectoralis major Biceps brachi Gluteus maximus Rectus femoris Gastrocnemius

Parts of the Muscular System

Parts of the Muscular System Trapezius Muscle

Parts of the Muscular System Latisimus Dorsi Muscle

Parts of the Muscular System Bicep & Tricep

Parts of the Muscular System Gluteus Maximus Muscle

Parts of the Muscular System Hamstring

The Three Hamstring Muscle Semitendinosus Muscle Semimembranosus Muscle Bicep Femoris Muscle

Calf Muscles Gastrocnemius & Soleus Muscle

Achilles Tendon

Extensor Muscles

Flexor Muscles

Major Pectoral

Abdominal Muscles Abdominal Muscles Internal Obliques External Obliques

The Quadriceps

Anterior Tibialis

Parts of the Muscular System Latissimus Dorsi Deltoid Trapezius Extensors Triceps Gluteals Hamstring Achille’s Tendon Soleus Gastrocnemius

The Muscular System Major Pectoral Biceps Flexors Sartorius Quadriceps Abdominals

Problems of The Muscular System Pulled or Torn Muscle Pulled or Torn Muscle –Treatment: Medical Help Strain: Soreness due to overwork Strain: Soreness due to overwork –Treatment: Rest, ice or heat

Problems of The Muscular System Tendonitis: Stretched or torn tendon. Tendonitis: Stretched or torn tendon. –Treatment: Rest and ice to possible surgery Cramp: Muscle unable to relax; feels tight and sore Cramp: Muscle unable to relax; feels tight and sore –Treatment: Message / Drink fluids

Problems of The Muscular System Muscular Dystrophy: Weakening of the skeletal muscles, eventually inability to walk or stand. Muscular Dystrophy: Weakening of the skeletal muscles, eventually inability to walk or stand. –Treatment: No Cure

The Skeletal / Muscular System Test Questions Latissimus Dorsi Deltoid Trapezius Extensors Triceps Gluteals Hamstring Achille’s Tendon Soleus Gastrocnemius Major Pectoral Biceps Flexors Sartorius Quadriceps Abdominals