1. Comparative Anatomy Muscles
Kardong
Chapter 10
Part 10

2. Muscles Two major muscle categories: Somatic muscles Visceral muscles
Operate head, trunk, limbs
Locomotion and orientation
Visceral muscles
Operate visceral skeleton
Digestion and respiratory movements

3. More on the two Muscle Groupings
Somatic muscles
Skeletal muscle
Striated and voluntary
Visceral muscles
Smooth muscle
Non-striated and involuntary
Exception- branchiomerics (unsegmented)

4. Skeletal Muscle Microanatomy
Figure 10.1 (book
figure 10.2).

5. Cardiac Muscle Microanatomy
Figure 10.2 (book
figure 10.3).

6. Smooth Muscle Microanatomy
Figure 10.3 (book
figure 10.4).

7. Skeletal Muscles Axial Appendicular Branchiomerics Trunk and tail
Insert on girdles, fins, or limbs
Branchiomerics
Attached to visceral skeleton

8. Origin of Muscle Groups Derived from Embryonic Myotomes
Figure (book figure 10.21).

9. Axial Musculature Shark Amphibians Mammals
Epaxial and hypaxial muscles
Body wall muscles
Amphibians
Epaxials above transverse process
Hypaxials along body wall proper
Mammals
Epaxials subdivided
Hypaxials more complex
Figure Trunk muscles of vertebrates.

10. Abdominal Muscle Groups - Amniotes
Epaxials
Transversospinalis, longissimus, iliocostalis
Hypaxials
Dorsomedials, laterals, ventrals
Laterals- external oblique, internal oblique, and transverse abdominus
Ventral- rectus abdominus
Figure Epaxial and hypaxial muscles

11. Epaxial and Hypaxial Muscles - Amniotes
Figure Specific epaxial muscles.
Figure Epaxial and hypaxial mucles.

12. Head Region
Figures Myotomes in the head, neck, and thoracic regions of the embryo.
Figure Axial muscle origin and innervation in vertebrate embryo.

13. Head Region In branchial region, somites are broken down
Ventral slips of postbranchial somites become hypobranchial musculature
Hypobranchial muscles give rise to:
Sternohyoid
Sternothyroid
Omohyoid
Tongue muslces
Geniohyoid
Hyoglossus
Styloglossus
Genioglossus
Lingualis propria
Figure (book figure ).

14. Appendicular Muscles Extrinsic Intrinsic
Origin on axial skeleton or fascia of trunk
Insert on girdles and limbs
Intrinsic
Origin on girdles or proximal skeletal elements of appendages
Insert on more distal skeletal elements

15. Intrinsic Muscles
Figure Intrinsic muscles of pectoral girdle and forelimbs of mammals and their homologues in reptiles.

16. Branchiomerics Arises from lateral mesoderm Mandibular (1st) arch
Hyoid arch
Arches IV to VI

17. Branchiomeric Muscles
Figure Branchiomeric muscles and their innervations (see book table 10.3).

18. Branchiomerics Mandibular (1st) arch Intermandibularis - digastic
Adductor mandibulae - masseter, temporalis
Hyoid arch
Sphincter coli
Platysma and mimetics
integumentary muscles
Arches IV to VI
Trapezius, sternomastoid,
cleidomastoid
Figure Branchiomeric muscles of gnathostomes.

19. Nerves Innervating Muscles
Figure Facial nerves to muscles.
Figure Cranial nerves.

20. Extrinsic Eye Muscles Six eyeball muscles 2 obliques 4 rectus
Superior and inferior on anterior portion
4 rectus
Arise in posterior portion of orbit
Innervated by oculomotor, trochlear, and abducens
Figure Innervation of eye muscle in embryo.

21. Extrinsic Eye Muscles
Figure Dorsal view of extrinsic muscles of the left eyeball .
Figure Lateral view of extrinsic muscles of eyeball.

22. Diaphragm Mammalian muscle structure
Near lungs and heart in abdominal cavity
Figure Human diaphragm.

23. Dermal or Integumentary Muscles
Fish & tailed amphibians- skin is firmly attached to musculature
Sphincter coli- first muscle to move skin
Subdivides down neck- platysma
Extrinsic and intrinsic muscle groups
Figure Evolution of mammalian facial muscles. Shows sphincter colli (SC) spreading into platysma (P).

24. Extrinsic Integumentary Muscles
Costocutaneous muscles - allows rectilinear motion (reptiles)
Panniculus carnosus - sheet surrounds body
Cutaneous maximus - to shake skin (higher mammals)
Patagial muscles - bat wings
Auricularis - moves human ear
Caninus muscle - arises with aggression
Intrinsic Integumentary Muscles
Arrectores plumarum (birds) & arrectores pilorum (mammals) - erects hair and feathers

25. Specialized Muscles Electric organs In elasmobranchs and bony fish
Modified hypaxial muscles
Figure Electric eel.

26. Vertebrates with Electric Organs
Figure (book figure 10.1).