Muscular System (Laboratory) PDF

Muscular System  The Muscular System Muscles are responsible for all types of body movement Three basic muscle types are found in the body 1. Skeletal muscle 2. Cardiac muscle 3. Smooth muscle © 2012 P...

Muscular System  The Muscular System Muscles are responsible for all types of body movement Three basic muscle types are found in the body 1. Skeletal muscle 2. Cardiac muscle 3. Smooth muscle © 2012 Pearson Education, Inc.  TYPES OF MUSCLES FEATURE SKELETAL MUSCLE CARDIAC MUSCLE SMOOTH MUSCLE Walls of hollow organs, LOCATION Attached to bones Heart blood vessels, glands CELL SHAPE Long, cylindrical Cylindrical, branched Spindle-shaped CONTROL Voluntary Involuntary Involuntary Compression of organs, FUNCTION Body movement Heart contraction vessels, peristalsis What type of muscle is this? Is it voluntary or involuntary? What type of muscle is this? Is it voluntary or involuntary? What type of muscle is this? Is it voluntary or involuntary?  All muscles share some terminology Prefixes myo and mys refer to “muscle” Prefix sarco refers to “flesh”  Muscle fiber - Individual muscle cells that makes up the skeletal muscles  Microscopic Anatomy of Skeletal Muscle Sarcolemma - specialized plasma membrane Myofibrils - long organelles inside muscle cell © 2012 Pearson Education, Inc.  Microscopic Anatomy of Skeletal Muscle Myofibrils are aligned to give distinct bands I band = light band, contains only thin filaments A band = dark band, contains the entire length of the thick filaments © 2012 Pearson Education, Inc. a. I band, which consists only of Regions of actin myofilaments. Sarcomere b. A darker, central region in each sarcomere, called an A band, extends the length of the myosin myofilaments. c. In the center of each sarcomere, called the H zone, which consists only of myosin myofilaments. d. The myosin myofilaments are anchored in the center of the sarcomere at the M line.  Microscopic Anatomy of Skeletal Muscle Sarcomere — contractile unit of a muscle fiber Organization of the sarcomere Myofilaments Thick filaments = myosin filaments Thin filaments = actin filaments © 2012 Pearson Education, Inc.  Microscopic Anatomy of Skeletal Muscle Sarcoplasmic reticulum - specialized smooth endoplasmic reticulum - has a relatively high concentration of Ca2+, which plays a major role in muscle - contraction. - release of Ca2+ from sarcoplasmic reticulum is a “switch” for muscle contraction © 2012 Pearson Education, Inc.  Muscle Names 1. Location - such as the pectoralis (chest) muscles 2. Size – gluteus maximum (large) largest muscle of the buttock 3. Shape – deltoid (triangular) muscle is triangular in shape 4. Orientation – fascicles could run straight (rectus) or at an angle (oblique). 5. Origin and insertion - brachioradialis (brachio, arm) muscle, which extends from the arm to the radius 6. Number of heads - biceps muscle has two heads (origins) 7. Function – abductors and adductors are the muscles that cause abduction and adduction  Movement is attained due to a Muscles and Body muscle moving an attached bone Movements Muscles are attached to at least two points Origin Attachment to an immoveable bone Insertion Attachment to a movable bone © 2012 Pearson Education, Inc.  Types of Body Movements Flexion Extension Decreases the angle of the Opposite of flexion joint Increases angle between Brings two bones closer two bones together Typical of straightening the Typical of bending hinge elbow or knee joints like knee and elbow Extension beyond 180° is or ball-and-socket joints hypertension like the hip © 2012 Pearson Education, Inc. © 2012 Pearson Education, Inc. Figure 6.13a © 2012 Pearson Education, Inc. Figure 6.13b  Types of Body Movements Rotation Movement of a bone around its longitudinal axis Common in ball-and- socket joints © 2012 Pearson Education, Inc.  Types of Body Movements Abduction Movement of a limb away from the midline Adduction Opposite of abduction Movement of a limb toward the midline © 2012 Pearson Education, Inc.  Types of Body Movements Circumduction Combination of flexion, extension, abduction, and adduction Common in ball- and-socket joints © 2012 Pearson Education, Inc.  Special Movements Dorsiflexion Lifting the foot so that the superior surface approaches the shin (toward the dorsum) Plantar flexion Depressing the foot (pointing the toes) “Planting” the foot toward the sole © 2012 Pearson Education, Inc.  Special Movements Inversion Turn sole of foot medially Eversion Turn sole of foot laterally © 2012 Pearson Education, Inc.  Special Movements Supination Forearm rotates laterally so palm faces anteriorly Radius and ulna are parallel Pronation Forearm rotates medially so palm faces posteriorly Radius and ulna cross each other like an X © 2012 Pearson Education, Inc.  Special Movements Opposition Move thumb to touch the tips of other fingers on the same hand © 2012 Pearson Education, Inc. Muscles of the Head and Neck  Muscles of the Facial Expression Muscle Origin Insertion Action Compresses the Maxilla, Buccinator Lips cheeks and lips mandible against teeth  Muscle Origin Insertion Action Depresses Depressor Lower Lip, mandible the angle of anguli oris near angle the mouth  Muscle Origin Insertion Action Levator Upper Lip, labii Maxilla Raises the upper lip nose superioris  Muscle Origin Insertion Action Skin of Raises the Occipitofrontalis Occipital eyebrow, nose eyebrows  Muscle Origin Insertion Action Orbicularis oculi Maxilla, frontal Encircles eye Closes the eyelids Muscle Origin Insertion Action Risorius Fascia of masseter Angle of the mouth Draws out the angle of the mouth  Muscle Origin Insertion Action Elevates and Zygomaticus Zygomatic Angle of abducts the upper major bone the mouth lip  Muscle Origin Insertion Action Orbicluaris Elevates Zygomaticus Zygomatic oris of the and abducts minor bone upper lip the upper lip Muscles of the Mastication  Muscle Origin Insertion Action Temporal Elevates and retracts Temporalis Mandible fossa mandible Muscle Origin Insertion Action Elevates and Masseter Zygomatic arch Mandible protracts mandible  Muscle Origin Insertion Action Lateral pterygoid Sphenoid Mandible Retracts and depresses mandible Medial pterygoid Sphenoid, maxilla Mandible Protracts and elevates mandible Muscles of the Neck  Muscle Origin Insertion Action Deep neck muscles – neck flexors, neck Vertebrae Base of the skull Flexors and extensors extensors FLEXION EXTENSION  Muscle Origin Insertion Action Sternum, Mastoid process of Individually rotates the head, together Sternocleidomastoid clavicle the skull flexes the neck and extends the head  Muscle Origin Insertion Action Skull, upper vertebral Extends the head and Trapezius Scapula column the neck Muscle Origin Insertion Action Fascia on the Depresses the mandilble, superior part Edge of the tightens the fascia of the Platysma of pectoralis mandible, lower neck and epresses lower major and part of face lip deltoid  Muscles of Trunk, Clavicle Shoulder, Arm Anterior muscles Deltoid Pectoralis major—adducts and Sternum flexes the humerus Pectoralis major Intercostal muscles Biceps External intercostals—raise rib brachii cage during inhalation Brachialis Internal intercostals—depress the Brachio - radialis rib cage to move air out of the lungs when you exhale forcibly (a) © 2012 Pearson Education, Inc.  Muscles of Trunk, Shoulder, Arm Scalene – Inspiration (Inhale), elevates the ribs © 2012 Pearson Education, Inc.  Pectoralis major © 2012 Pearson Education, Inc.  Intercostal muscles © 2012 Pearson Education, Inc.  Scalene © 2012 Pearson Education, Inc.  Muscles of the Abdominal Girdle Muscles of Trunk, Shoulder, Arm Rectus abdominis—flexes vertebral column and compresses abdominal contents (defecation, childbirth, forced breathing) Transversus abdominis— compresses abdominal contents © 2012 Pearson Education, Inc.  Rectus abdominis © 2012 Pearson Education, Inc.  Transversus © 2012 Pearson Education, Inc. abdominis  Muscles of the Abdominal Girdle Muscles of Trunk, Shoulder, Arm External oblique—flex vertebral column; rotate trunk and bend it laterally Internal oblique—flex vertebral column; rotate trunk and bend it laterally © 2012 Pearson Education, Inc.  Internal and External oblique © 2012 Pearson Education, Inc.  Muscles of Trunk, Shoulder, Posterior muscles Arm Trapezius—elevates, depresses, adducts, and stabilizes the scapula Latissimus dorsi—extends and adducts the humerus Quadratus lumborum—flexes the spine laterally Deltoid—arm abduction © 2012 Pearson Education, Inc.  Trapezius © 2012 Pearson Education, Inc.  Latissimus dorsi © 2012 Pearson Education, Inc.  Quadratus lumborum © 2012 Pearson Education, Inc.  Deltoid © 2012 Pearson Education, Inc.  Muscles of Trunk, Shoulder, Arm Muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the humerus include: Pectoralis major Latissimus dorsi Deltoid © 2012 Pearson Education, Inc.  Muscles of Trunk, Shoulder, Arm Erector spinae—back extension © 2012 Pearson Education, Inc.  Erector spinae © 2012 Pearson Education, Inc.  Clavicle Muscles of the Upper Limb Deltoid Biceps brachii—supinates forearm, Sternum flexes elbow Pectoralis Brachialis—elbow flexion major Brachioradialis—weak muscle; Biceps brachii elbow flexion Brachialis Triceps brachii—elbow extension Brachio (antagonist to biceps brachii) - radialis © 2012 Pearson Education, Inc. (a)  Biceps brachii © 2012 Pearson Education, Inc.  Brachialis © 2012 Pearson Education, Inc.  Occipital bone Muscles of the Upper Sternocleidomastoid Spine of scapula Limb Trapezius Deltoid (cut) Deltoid Triceps brachii— elbow extension Triceps (antagonist to brachii Latissimus biceps brachii) dorsi Humerus Olecranon process of (a) ulna (deep to tendon) © 2012 Pearson Education, Inc.  Triceps brachii © 2012 Pearson Education, Inc.  Muscles of the forearm, which insert on the hand bones and cause their movement includes: Wrist and Finger Movements Flexor carpi (radialis, ulnaris)— wrist flexion Flexor digitorum— finger flexion Extensor carpi— wrist extension Extensor digitorum—finger extension © 2012 Pearson Education, Inc. Muscles of the Upper Limb  Flexor carpi Flexor carpi radialis ulnaris © 2012 Pearson Education, Inc.  Flexor digitorum © 2012 Pearson Education, Inc.  Extensor Extensor © 2012 Pearson Education, Inc. carpi digitorum  Muscles of the Lower Limb Muscles causing movement at the Gluteus hip joint include: medius Gluteus maximus—hip Gluteus maximus extension Adductor Gluteus medius—hip abduction, magnus steadies pelvis when walking Iliotibial tract Iliopsoas—hip flexion, keeps the Biceps upper body from falling femoris Hamstring group Semitendinosus backward when standing erect Semimembranosus Adductor muscles—adduct the thighs Gastrocnemius © 2012 Pearson Education, Inc. (a)  Gluteus medius Gluteus maximus Adductor magnus Iliotibial tract Biceps femoris Semitendinosus Hamstring group Semimembranosus Gluteus maximus Gastrocnemius © 2012 Pearson Education, Inc. (a)  Gluteus medius Gluteus maximus Adductor magnus Iliotibial tract Biceps femoris Semitendinosus Hamstring group Semimembranosus Gluteus medius © 2012 Pearson Education, Inc. (a) Gastrocnemius  Iliopsoas © 2012 Pearson Education, Inc.  Adductor muscles © 2012 Pearson Education, Inc.  Muscles of the Lower Limb Gluteus Muscles causing movement at the medius knee joint Gluteus maximus Hamstring group—thigh Adductor extension and knee flexion magnus Biceps femoris Iliotibial tract Semimembranosus Biceps Semitendinosus femoris Semitendinosus Hamstring group Semimembranosus Gastrocnemius © 2012 Pearson Education, Inc. (a)  Hamstring group © 2012 Pearson Education, Inc.  12th Muscles of the Lower Limb 12th rib thoracic vertebra Muscles causing movement Iliac crest lliopsoas Psoas major at the knee joint lliacus 5th lumbar vertebra Sartorius—flexes the thigh Anterior superior iliac spine Inguinal Quadriceps group— Sartorius ligament extends the knee Adductor group Rectus femoris Quadriceps (Adductor Rectus femoris Vastus lateralis muscles) Vastus muscles (three) Vastus medialis Patella Patellar ligament (c) © 2012 Pearson Education, Inc.  Sartorius © 2012 Pearson Education, Inc.  Quadriceps group © 2012 Pearson Education, Inc.  Muscles of the Lower Limb Muscles causing movement at ankle and foot Fibularis longus Gastrocnemius Gastrocnemius Tibialis anterior— Tibia Fibularis brevis dorsiflexion, foot inversion Tibialis anterior Soleus Extensor digitorum Extensor digitorum longus Fibularis longus—toe extension and tertius Soleus Soleus dorsiflexion of the foot Fibularis muscles—plantar Calcaneal Calcaneal (Achilles) (Achilles) tendon tendon flexion, foot eversion Medial malleolus Lateral Soleus—plantar flexion malleolus (a) (b) © 2012 Pearson Education, Inc.  Tibialis Extensor Fibularis Soleus anterior digitorum muscles © 2012 Pearson Education, Inc. longus