Download Week 5--Muscular System

Bio 221 - Lab 5
Muscular System
I. Muscular System: The muscular system consists of organs called
muscles that are responsible for moving the skeleton. Muscles are
composed of skeletal muscle fibers organized by various layers of
connective tissue, and are well supplied with blood vessels and
nerves. Be able to identify the following muscles and attachments
on all of the models in which they are found in lab. Know the
components (muscles) of assigned muscle groups and their group
name. Actions are also assigned for some designated muscles. DO
NOT DISASSEMBLE MUSCLE MODELS!
A. Skeletal Muscle Tissue (pages 186, 188)
 Muscle fibers
o Striations (Dark bands & Light bands)
o Nuclei
 Axon terminals
 Neuromuscular/Myoneural junction
B. Neuromuscular junction (pages 186, 189, 230)
 Endomysium
 Muscle fiber
o Sarcolemma
o Motor end plate (folded region of sarcolemma)
o Sarcoplasm (fluid between organelles)
o Nucleus
o Myofibril (contractile organelle)
 Motor neuron
o Myelinated axon
o Axon terminal(s)
 Schwann cell(s)/Neurolemmocyte
C. Head & Neck muscles
 Frontalis
 Temporalis
 Occipitalis
 Orbicularis oculi
 Orbicularis oris
 Buccinator
 Zygomaticus
 Masseter
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D.
E.
F.
G.
 Platysma
 Sternocleidomastoid
Superficial & Deep Trunk muscles – Anterior
 Pectoralis major (E-5)
 Pectoralis minor (E-5)
 Serratus anterior
 External intercostals (superficial)
 Internal intercostals (deep)
 Rectus abdominis
 External oblique
 Internal oblique (deep to external oblique)
Superficial & Deep Trunk muscles – Posterior
 Trapezius
 Latissimus dorsi
 Deltoid (shoulder, anterior & posterior)
 Splenius (deep to trapezius in neck)
 Rhomboid E-6 (deep; between scapula & vertebrae)
 Supraspinatus E-6 (above spine of scapula)
 Infraspinatus E-6 (below spine of scapula)
 Teres major E-6 (inferior to infraspinatus)
 Subscapularis (fills subscapular fossa)
Arm muscles
 Biceps brachii
 Triceps brachii
 Brachialis
Forearm muscles
 Brachioradialis
 Extensor digitorum
 Flexor carpi radialis
 Extensor carpi radialis
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H. Leg muscles – Anterior thigh
 Tensor fasciae latae E-7 (between iliac crest & iliotibial
tract)
 Vastus lateralis
 Rectus femoris
 Vastus medialis
 Sartorius
 Iliopsoas
 Adductor longus E-7 (anterior to gracilis in thigh)
 Gracilis (this is medial, not anterior or posterior)
I. Leg muscles – Posterior thigh
 Gluteus maximus
 Gluteus medius
 Adductor magnus
 Semitendinosus
 Semimembranosus
 Biceps femoris
J. Lower leg muscles – Anterior
 Tibialis anterior
 Extensor digitorum longus
 Fibularis longus (this is lateral, not anterior or posterior)
K. Lower leg muscles – Posterior
 Soleus
 Gastrocnemius
L. Muscle Groups
 Epicranius Group
o Frontalis
o Occipitalis
 Quadriceps Group (only these 3 of 4 are assigned)
o Rectus femoris
o Vastus medialis
o Vastus lateralis
 Hamstring Group
o Biceps femoris
o Semitendinosus
o Semimembranosus
 Erector Spinae Group (just know this group name)
 Flexors of the wrist
 Extensors of the wrist
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M. Attachments (These structures attach muscles to other
structures, are composed of dense fibrous C.T., and appear white
in color on the lab models.)
 (Galea aponeurotica/Cranial aponeurosis
 Linea alba (medial white line along abdomen)
 Ligamentum nuchae (medial posterior neck)
 Dorsal lumbar fascia (large aponeurosis, lumbar region)
 Iliotibial tract/band
 Patellar tendon/Quadriceps femoris tendon, E-7 (between
patella & quadriceps group)
 Calcaneal tendon/Achille’s tendon
N. Actions – The following is a list of muscles for which you must
learn actions. Refer to your lecture textbook for the primary
action of each of these muscles. For muscles that have more than
one listed action, learn the action that pertains to the joint
within the parenthesis.
 Frontalis
 Orbicularis oculi
 Orbicularis oris
 Zygomaticus
 Masseter
 Buccinator
 Sternocleidomastoid (head)
 Platysma
 Pectoralis major
 Rectus abdominis
 Biceps brachii (elbow)
 Deltoid
 Iliopsoas
 Quadriceps group (knee)
 Extensor digitorum longus
 Latissimus dorsi
 Erector spinae
 Triceps brachii
 Hamstring group (knee)
 Flexor carpi radialis (wrist)
 Extensor carpi radialis (wrist)
 Extensor digitorum
 Gluteus maximus
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