Transcript Slides 6.32

Essentials of Human Anatomy & Physiology
Seventh Edition
Elaine N. Marieb
Chapter 6
The Muscular System
Slides 6.32 – 6.44
Lecture Slides in PowerPoint by Jerry L. Cook
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Types of Ordinary Body Movements
 Flexion
 Extension
 Rotation
 Abduction
 Circumduction
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.32
Body Movements
Figure 6.13
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.33
Special Movements
 Dorsifelxion
 Plantar flexion
 Inversion
 Eversion
 Supination
 Pronation
 Opposition
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.34
Types of Muscles
 Prime mover – muscle with the major
responsibility for a certain movement
 Antagonist – muscle that opposes or
reverses a prime mover
 Synergist – muscle that aids a prime
mover in a movement and helps prevent
rotation
 Fixator – stabilizes the origin of a prime
mover
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.35
Naming of Skeletal Muscles
 Direction of muscle fibers
 rectus (straight)
 oblique (slanted)
 Relative size of the muscle
 maximus (largest)
 minimus (smallest)
 longus (long)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.36a
Naming of Skeletal Muscles
 Location of the muscle
many muscles are named for bones
(e.g., temporalis)
 Number of origins
biceps (two heads)
triceps (three heads)
quadriceps (four heads)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.36b
Naming of Skeletal Muscles
 Location of the muscles origin and
insertion
 Example: sterno (on the sternum)
 Shape of the muscle
 Example: deltoid (triangular)
 Action of the muscle
 Example: flexor and extensor (flexes or
extends a bone)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Head and Neck Muscles
 Facial Muscles
 Frontalis – muscle covering frontal
bone; allows for lifting eyebrows and
wrinkling forehead
 Orbicularis Oculi – circular muscle
around eye; allows closing, squinting,
blinking, and winking of eye
 Orbicularis Oris – circular muscle
around lips; closes mouth and
protrudes lips
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Head and Neck Muscles
 Facial Muscles (cont’d)
 Buccinator – runs horizontally along
cheek and inserts into O. oris; flattens
cheek in whistling, blowing, and
chewing
 Zygomaticus – runs from side of
mouth up to cheekbone; raises corner
of mouth upward
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Head and Neck Muscles
 Chewing Muscles
 Masseter – covers the angle of the
lower jaw, running from zygomatic
process to mandible; closes the jaw
 Temporalis – covers temporal bone;
acts as a synergist/aids the masseter
in closing the jaw
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Head and Neck Muscles
 Neck Muscles
 Platysma – covers anterolateral neck,
originates from chest and inserts into
area around mouth; pulls corners of
mouth downward
 Sternocleidomastoid – paired
muscles with two heads originating
from the sternum and clavicle, then
inserting into the mastoid process;
bend the head down forward and to
the sides
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Head and Neck Muscles
Figure 6.14
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.38
Trunk Muscles
 Anterior Trunk Muscles
 Pectoralis Major – covers upper part
of chest, originates from shoulder
girdle and first six ribs, inserts on
proximal end of humerus; adducts
and flexes arm
 Intercostal Muscles – between the
ribs; external intercostals raise rib
cage to allow air in, internal
intercostals depress cage to force air
out
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
 Anterior Trunk Muscles (cont’d)
 Rectus Abdominals – paired muscles
running from pubis to rib cage; flex
the vertebral column and compress
the abdominal contents
 External Oblique – paired muscles of
the lateral walls of the abdomen,
running from the last eight ribs to the
ilium; flex the vertebral column and
rotate the trunk and bend laterally
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
 Anterior Trunk Muscles (cont’d)
 Internal Oblique – paired muscles deep
to external obliques, originate from iliac
crest and insert into the last three ribs;
same function as external obliques
 Transversus abdominals – deepest
muscle of abdominal wall with fibers
running horizontally, originates from
lower ribs and iliac crest and inserts into
the pubis; compresses the abdominal
contents
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
 Anterior Arm Muscles
 Biceps Brachii – originates from the
shoulder girdle and inserts into the
radial tuberosity; flexes and supinates
the forearm
 Brachialis – deep to the bicep; flexes
the forearm
 Brachioradialis – originates from the
humerus and inserts into the distal
forearm
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
Figure 6.15
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.39
Trunk Muscles
 Posterior Trunk Muscles
 Trapezius – paired muscles with origin
running from base of occipital bone down
to the end of the thoracic vertebrae, insert
on scapular spine and clavicle; extend the
head and move the scapula
 Latissimus Dorsi – large paired muscles of
lower back, originates from lower back
and ilium then inserts into proximal end of
humerus; extends and adducts humerus
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
 Posterior Trunk Muscles (cont’d)
 Erector Spinae – paired set of three
muscle columns that extend the length
of the vertebral column; extend the
vertebral column
 Deltoid – originates from the scapular
spine and clavicle and inserts into the
deltoid tuberosity of humerus; abduct
the arm
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Trunk Muscles
 Posterior Arm Muscles
 Triceps Brachii – originates from
shoulder girdle and proximal humerus,
inserts into olecranon process of ulna;
extends the forearm (antagonist of
biceps)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Deep Trunk and Arm Muscles
Figure 6.16
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.40
Lower Limb Muscles
 Pelvis, Hip and Thigh Muscles
 Gluteus Maximus – originates from
sacrum and ilium and inserts on
gluteal tuberosity of femur, forms the
buttocks; extends the thigh,
especially when climbing and jumping
 Gluteus Medius – originates from
ilium and inserts into femur; abducts
the thigh with the hip
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Lower Limb Muscles
 Pelvis, Hip and Thigh Muscles (cont’d)
 Iliopsoas – originates from the iliac
bone and lower vertebrae and inserts
on the lesser trochanter of the femur;
flexes the leg at the hip
 Adductor Muscles – originate from
the pelvis and inserts medially
towards the proximal end of the
femur; adducts the thigh
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Lower Limb Muscles
 Pelvis, Hip and Thigh Muscles (cont’d)
 Hamstring group – three muscles
originating from the ischial tuberosity
and inserts onto both sides of the
proximal end of the tibia; extend the
leg
 Sartorius – originates from anterior
iliac crest and inserts into medial side
of tibia; flexes the thigh
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Lower Limb Muscles
 Pelvis, Hip and Thigh Muscles (cont’d)
 Quadriceps group – four muscles that
make the anterior thigh, originating
from the femur or pelvis and inserting
into the tibial tuberosity; extends the
knee and flexes the hip
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Muscles of the Pelvis, Hip, and Thigh
Anterior View
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Posterior View
Slide 6.41
Lower Limb Muscles
 Lower Leg Muscles
 Tibialis Anterior – originates from
upper tibia and inserts at the tarsals,
running parallel to anterior crest; acts
to dorsiflex and invert the foot
 Extensor Digitorum Longus –
originates from lateral tibial condyle
and proximal radius and inserts into
toes 2-5, running just lateral to tibialis;
extends toes and dorsiflexes foot
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Lower Limb Muscles
 Lower Leg Muscles (cont’d)
 Gastrocnemius – forms calf muscle,
two head originate from each side of
distal femur and inserts onto the heel
bone; main part of plantar flexion
 Soleus – originates from tibia and
inserts into the tarsals, just deep to
gastrocnemius; aids in plantar flexion
of foot
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.37
Muscles of the Lower Leg
Figure 6.19
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.42
Superficial Muscles: Anterior
Figure 6.20
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.43
Superficial Muscles: Posterior
Figure 6.21
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 6.44