Ms Hays Spring 2014 External Nares Nostrils Pair of openings on each side of the head cranial from the eyes Taken up into the smaller of the two openings and expelled through the larger openings ID: 531457
Download Presentation The PPT/PDF document "External Structures of Dog Fish Shark" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
External Structures of Dog Fish Shark
Ms. Hays – Spring 2014Slide2
External Nares (Nostrils)
Pair of openings on each side of the head
cranial
from the eyes
Taken up into the smaller of the two openings and expelled through the larger openings
Water passes a sensory membrane allowing the shark to detect chemicals in water Slide3
Spiracles
Small openings
caudal
behind the eyes
Provides oxygenated blood directly to the eye and brain through a separate blood vesselSlide4
Spiracles
NostrilsSlide5
Mouth
Location: front of the head
Function: to eat; used for the intake of water that passes through the gillsSlide6
Gill Slits
5 vertical slits
Location: in front of the
pectoral
fin
Function: to take the oxygen from the water passing over the gills and discharge carbon dioxideSlide7
What is the function of the gill slits in this picture?
Gas Exchange! Slide8
Lateral Line
Location: extends noticeably from the pectoral fin past the pelvic fin.
Function: senses tiny pressure disturbances in the water
The lateral line is a line of pores that run along each side of the shark that help the shark orient to movement & sound. Slide9
Cloaca
Location: between the pelvic fins & claspers
Function: Opening for the sex organs as well as being used for excretory waste
Slide10
Clasper
Only present in males!
Location: down the middle of each pelvic fin
Function: Used to introduce the sperm into the cloaca of the femaleSlide11
What is the name of the structure that is on the side of the pelvic fins that is only present in males?
ClaspersSlide12
Fins
5 fins:
1
st
& 2
nd
Dorsal Fin – anti-roll stabilizing fins
Pectoral Fin – steering fins
Pelvic Fin – stabilizing fins
Caudal Fin – provides thrust Slide13
What are the names of the 5 fins of a shark?
1
st
Dorsal Fin2
nd
Dorsal Fin
Pectoral Fin
Pelvic Fin
Caudal FinSlide14
Rostrum
Pointed snout located at the front of the headSlide15
Dorsal Spines
Used defensively by the shark
Each has a poison gland associated with itSlide16
What is a characteristic of the lateral lines and what is a characteristic of dorsal spines?
Lateral Lines: senses tiny pressure disturbances in water
Dorsal Spines: used as a defensive mechanism, each has a poison gland associated with itSlide17
Denticles
Tooth-like scales on the surface of the sharks skin
Reduce drag and allow sharks to swim more silently & smoothly.Slide18
What is one characteristic of the dermal
denticles
on the surface of the sharks skin?
Tooth-like
Used to allow sharks to swim more silently & smoothlySlide19
Ampullae of
Lorenzini
Small vesicles and pores that form part of an extensive sensory network system.
Found on the head of the shark
Detect weak magnetic fields produced by other fishes
This enables the shark to locate prey that are buried in the sand or to orient to nearby movement
They may also allow sharks to detect changes in water temperatureSlide20
Where are the Ampullae of Lorenzini located on the shark?
HeadSlide21
Nictitating Membrane
A membrane that is present over the eyes that covers & protects the eyes during feeding.