How did you position your shark to remove the dorsal spines? I positioned my shark to be dorsal side up and have its ventral side facing down.
Where are the dorsal spines located on a shark?
Two large, sharp, mildly poisonous dorsal spines are located in front of each dorsal fin.
How is the shark’s nose different from humans?
Sharks do have nostrils, but unlike humans, they don’t serve the dual purpose of smelling and breathing—instead sharks breathe through their gills. Their noses don’t connect to their throat like ours do nor do they have lungs.
What is the function of the gill slits on a dogfish shark?
The gill slits close and the pharyngeal chamber expands to suck in water. When the pharynx is filled, the mouth closes and the gill chambers expand and fill with water. Then the gill slits open and the chambers constrict to flush out the water.
What membranes do you have to cut through to enter the body cavity of the shark?
1. Remove the liver by cutting at its cranial end. 2. Cut through the esophagus where it enters the body cavity above the stomach.
What is the purpose of a shark’s dorsal fin?
Dorsal fins stabilize the shark, keeping it from rolling to the side and helping it swim in a straight line. The trailing edge of the first dorsal fin may create a low pressure area extending to the tail, increasing the efficiency of the tail’s forward thrust and helping to conserve energy.
Why do sharks have two dorsal fins?
The two dorsal fins work together to stabilize the shark and stop him from tipping to one side. The dorsal fins are so critical that some species, like the Spiny Dogfish, use poisoned spines to protect them against possible predation.
What happens when you touch a sharks nose?
Shark studies have even found that touching a shark’s snout can cause it to halt mid-motion and not attack. The reason could be the tiny electrical receptors called ampullae of Lorenzini that speckle the area around sharks’ noses and mouths.
Can sharks smell blood?
Sharks can smell blood from hundreds of meters away—in concentrations as low as one part per million (ppm).
Can sharks sneeze?
Many animals, including humans, elephants, pandas and even seals, can sneeze. Sharks unfortunately cannot. To be able to sneeze, an animal needs to move air (or water) from the lungs through its nose to the outside. Sharks have two nostrils (called nares) below their snout that are used for smelling.
What is the difference between gill slits and gills?
Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys.
Why do sharks have multiple gill slits?
Some sharks have spiracles, which are special gill slits located just behind the eyes. They supply oxygen directly to the eyes and brain of the shark. Bottom dwelling sharks like the angelsharks use this extra respiratory organ to breathe while at rest on the sea floor.
What do gill lamellae do on a shark?
…of each filament constituting the gill lamellae draws a water current through the gill, which provides oxygen, but more importantly now sieves food from this current and transfers such material along tracts in the gill axes or their ventral margins (bound in mucus) toward the labial palps.
Why is it hard to cut through the pectoral girdle of a shark?
Why do you think cutting through the pectoral girdle may have been difficult? The pectoral girdle is in a location where the cartilage is very thick. The shark has two dark-colored kidneys on either side of the midline. The shark regulates its urinary system in a way unique compared to most other vertebrates.
What is the largest organ in the shark?
Liver
Liver: Taking up roughly 80% of the shark’s internal body cavity, the liver is the largest of sharks’ organs. The liver stores energy as dense oil which helps the shark with buoyancy, its ability to float. It also works as a part of the digestive system and helps filter toxins out of the shark’s blood.
What consist the food of the Frog is the mouth cavity well provided for grinding its food?
Frogs catch their food (such as insects and flies) with the help of its stick tongue and mixes it with the saliva. The teeth’s present in the upper jaw are called the maxillary teeth, it helps in grinding the ingested food before it is swallowed.
Why do sharks expose their dorsal fins?
Sharks can be lured to the surface with floating bait and, in investigating such hand-outs, sometimes their dorsal fins break the surface of the water. Sometimes sharks enter water so shallow that they can barely swim, and — as a result — their dorsal fins sometimes poke through the surface.
Can sharks move their dorsal fins?
Sharks have two sets of paired fins on the sides of their body, in the same general position as the main wings and horizontal tail wings of a plane. The shark can position these fins at different angles, changing the path of the water moving around them.
Can a shark survive without its dorsal fin?
Statement of significance: Despite the importance of the first, larger dorsal fin in maintaining shark swimming stability, adult reef sharks can survive without it.
Do sharks have balls?
Testes. Most male fish have two testes of similar size. In the case of sharks, the testes on the right side is usually larger. The primitive jawless fish have only a single testis, located in the midline of the body, although even this forms from the fusion of paired structures in the embryo.
Do sharks get attracted to period blood?
A shark’s sense of smell is powerful – it allows them to find prey from hundreds of yards away. Menstrual blood in the water could be detected by a shark, just like any urine or other bodily fluids. However, there is no positive evidence that menstruation is a factor in shark bites.