Shark Muscles Flashcards
Three regions of shark body
Head: tip of snout to the cranial border of pectoral fin
Trunk: between pectoral and pelvic fins
Tail: caudal to pelvic fin
Countershading
Dorsal side of the trunk is darker than the ventral side
Allows shark to better blend into its environment
Heterocercal
The dorsal lobe of the tail fin is larger than the ventral lobe
Nares
Cranial and ventral to eyes
Which open into blind-ended olfactory sacs for chemoreception
Lateral line system
Sense vibrations and movement in the water
Composed of bundles of sensory cells and canals located within the skin
Lateral line
Largest canal from the lateral line system
Light, thin stripe extends just above the most lateral side of trunk
Ampullae of Lorenzini
Modified portion of the lateral line system sensitive to electrical fields
Endolymphatic ducts
Connect the vestibular apparatus to the outside of the body though endolymphatic pores
Spiracle
Function unknown in sharks
Cloaca
Urinary and digestive track of both sexes empty via cloaca
Female urinary tract: Urinary papilla
Male urinary tract: Urogential papilla
Axial musculature arises from
Myotomes that differeniate from somites
Pectoral extensors
DORSAL
O: Scapular process and adjacent fascia
I: Radials and Ceratotrichia
Pectoral Flexors
VENTRAL
O: Coracoid bar
I: Radials and Ceratotrichia
Pelvic Extensors - Superficial Part
DORSAL
O: Iliac process of puboischiac bar
I: Radials and Ceratotrichia
Pelivic Extensors - Deep Part
DORSAL
O: Metaptyergium
I: Radials and Ceratotrichia
