Presentation 11: Muscles

Question 1

Tendons

Answer 1

Connective tissue that connects muscle to bone (ex. collagen fibers) and include aponeuroses and fascia

Question 2

Aponeuroses

Answer 2

Thin, flat sheets of connective tissue that connects muscle to bone or organs

Question 3

Fascia

Answer 3

Layers of loose connective tissue that connect muscles to muscles

Question 4

Origin

Answer 4

Where muscles attach to structures w/ fixed attachment

Question 5

Insertion

Answer 5

Where muscles attach to structures and are free to move

Question 6

Flexor

Answer 6

Bend limbs together (reduces the angle between two structures)

Question 7

Extensor

Answer 7

Increases angle between 2 structures (straighten limbs out)

Question 8

Adductor

Answer 8

move limbs towards midline of body (decrease angle)

Question 9

Abductor

Answer 9

move limbs away from midline of body (increase angle)

Question 10

Levator

Answer 10

Special kind of adductor to close jaw

Question 11

Depressor

Answer 11

Special kind of abductor, opens jaw

Question 12

Protractor

Answer 12

Contraction leads to projection of a part away from its base (eg. sticking tongue out)

Question 13

Retractor

Answer 13

Brings projected part (from protractor) back towards its base

Question 14

Constrictor

Answer 14

Surrounds tubes/openings and constricts (generally to close)

Question 15

Sphincter

Answer 15

Type of constrictor e.g. controls digestive system

Question 16

Dilators

Answer 16

acts opposite to constrictor to open orifice closed by constrictors/sphincters

Question 17

Somatic muscles

Answer 17

one category of grouped muscles based on embryonic origin derive from myotomes and include body wall, tail muscles, hypobranchial muscles, tongue muscles, appendicular (limb) muscles, and the extrinsic muscles of the eye. generally voluntary

Question 18

Visceral Muscles

Answer 18

one category of grouped muscles based on embryonic origin, derive from endoderm/migrated neural crest cells, include muscles surrounding organs, surrounding blood vessels, intrinsic muscles of the eye, branchiomeric muscles (gills in embryos), cardiac muscle, erectors

Question 19

Skeletal Muscles

Answer 19

Striated, voluntary, associated w/ skeleton

Question 20

Cardiac Muscles

Answer 20

Striated, involuntary, only in the heart

Question 21

Smooth Muscles

Answer 21

Non-striated, involuntary, associated with visceral organs

Question 22

Axial Muscles

Answer 22

Ancestrally segmented, metameric (have myomers and myosepta)
Associated with vertebral column
Horizontal septum divides into epaxial (dorsal) and hypaxial (ventral) muscles
At the gill area, dorsal = epibranchial and ventral = hypobranchial

Question 23

Branchiomeric muscles

Answer 23

Associated w/ the gills
Gill arch #4 = constrictors, levators, interarcuals, and adductors (mandibular and hyoid arches lack adductors and interarcuals)

Question 24

Appendicular muscles

Answer 24

Associated w/ limbs/appendicular skeleton
Extrinsic (start on axial skeleton -> appendicular)
Intrinsic (start on appendicular and go distally)
or primary/limb bud: new muscles, evolve with the limb
or secondary appendicular muscles: hypaxial or branchiomeric muscles

Question 25

Branchiomeric constrictors

Answer 25

Associated w/ dorsal/ventral skeletal elements
ex. Dorsal constrictors: Adductor Mandibulae, Dorsal Hyoid Constrictor, etc.
ex. Ventral Constrictors: Intermandibularis and Interhyoideus

Question 26

Branchiomeric Levators

Answer 26

Associated between dorsal gill elements and axial skeleton
ex. Levator palatoquadrati, Levator Hyomandibulae, Cucullaris

Question 27

Branchiomeric Interarcuals

Answer 27

connect epibranchials to pharyngobranchials

Question 28

Branchiomeric Adductors

Answer 28

epibranchial to ceratobranchial connection

Question 29

Agnathan diversity

Answer 29

• Axial musculature not divided dorsa-ventrally
• Lack branchiomeric muscles

Question 30

Gnathostomes

Answer 30

• Horizontal septum divides muscles into epaxial and hypaxial
• Hypob
• Hypobranchials help with opening and closing the jaws and gills