BIOLOGY 250 MUSCLES/TERMINOLOGY EXAM 1 WITH
ALL CORRECT & VERIFIED ANSWERS (UPDATED TO
PASS)
Pectoral Fin Muscles
Extensor or Abductor Correct answer-Fan-shaped muscle appears on dorsal surface of the fin
Origin: Scapular process and adjacent fascia
Insertion: Basal and radial pterygiophores
Action: Extends or abducts (elevates) pectoral fin
Pectoral Fin Muscles
Flexor or Adductor Correct answer-Fan-shaped muscle appears on ventral surface of the fin
Origin: Coracoid portion of the scapulocoracoid bar
Insertion: Basal and radial pterygiophores
Action: Flexes or adducts (depresses) the pectoral fin
Pelvic Fin Muscles
Extensor or Abductor Correct answer-Muscle appears on dorsal surface of the fin
Origin: From the trunk myomeres, iliac process of puboischiadic bar and metapterygium
Insertion: Pterygiophores; in males, slips of the muscle extend onto the surface of the clasper and
insert there
Action: Extends or abducts (elevates) the pelvic fin; in males, the slips inserted on the clasper move
that organ during copulation
Pelvic Fin Muscles
Flexor or Adductor Correct answer-Ventral muscle consisting of proximal and distal portion
Origin: Proximal portion: Linea alba, puboischiadic bar; Distal portion: Metapterygium
Insertion: Proximal portion: Metapterygium; Distal portion: Pterygiophores; in males, slips of the
muscle extend onto the clasper and insert there
Action: Flexes or adducts (depresses) the pelvic fin; in males, the slips inserted on the clasper move
that organ during copulation
Visceral Arch I
Mandibular Arch Correct answer-Innervated by Cranial Nerve V (Trigeminal)
Levators
Levator Palatoquadrati Correct answer-Narrow band-like muscle lying anterior to spiracularis
muscle and spiracle
Origin: Otic capsule
Insertion: Palatoquadrate
Action: Elevates the palatoquadrate (upper jaw)
Dorsal Constrictors
Spiracularis Correct answer-Narrow band-like muscle lying anterior to spiracle
Adheres closely to levator palatoquadrati muscle and wall of spiracle
Origin: Otic capsule
Insertion: Palatoquadrate cartilage
Action: Elevates palatoquadrate (upper jaw)
Dorsal Constrictors
ALL CORRECT & VERIFIED ANSWERS (UPDATED TO
PASS)
Pectoral Fin Muscles
Extensor or Abductor Correct answer-Fan-shaped muscle appears on dorsal surface of the fin
Origin: Scapular process and adjacent fascia
Insertion: Basal and radial pterygiophores
Action: Extends or abducts (elevates) pectoral fin
Pectoral Fin Muscles
Flexor or Adductor Correct answer-Fan-shaped muscle appears on ventral surface of the fin
Origin: Coracoid portion of the scapulocoracoid bar
Insertion: Basal and radial pterygiophores
Action: Flexes or adducts (depresses) the pectoral fin
Pelvic Fin Muscles
Extensor or Abductor Correct answer-Muscle appears on dorsal surface of the fin
Origin: From the trunk myomeres, iliac process of puboischiadic bar and metapterygium
Insertion: Pterygiophores; in males, slips of the muscle extend onto the surface of the clasper and
insert there
Action: Extends or abducts (elevates) the pelvic fin; in males, the slips inserted on the clasper move
that organ during copulation
Pelvic Fin Muscles
Flexor or Adductor Correct answer-Ventral muscle consisting of proximal and distal portion
Origin: Proximal portion: Linea alba, puboischiadic bar; Distal portion: Metapterygium
Insertion: Proximal portion: Metapterygium; Distal portion: Pterygiophores; in males, slips of the
muscle extend onto the clasper and insert there
Action: Flexes or adducts (depresses) the pelvic fin; in males, the slips inserted on the clasper move
that organ during copulation
Visceral Arch I
Mandibular Arch Correct answer-Innervated by Cranial Nerve V (Trigeminal)
Levators
Levator Palatoquadrati Correct answer-Narrow band-like muscle lying anterior to spiracularis
muscle and spiracle
Origin: Otic capsule
Insertion: Palatoquadrate
Action: Elevates the palatoquadrate (upper jaw)
Dorsal Constrictors
Spiracularis Correct answer-Narrow band-like muscle lying anterior to spiracle
Adheres closely to levator palatoquadrati muscle and wall of spiracle
Origin: Otic capsule
Insertion: Palatoquadrate cartilage
Action: Elevates palatoquadrate (upper jaw)
Dorsal Constrictors
