Question 2 of 21

A shark has to swim to:

... All sharks have to swim to catch their prey and avoid their predators,

Question 3 of 21

Sharks move their bodies _____ while swimming.

... Sharks move their bodies side-to-side while swimming in a wavelike movement, turning their heads first one way, then another, which propels their bodies forward.

Question 4 of 21

The fact that a shark will drown if it stops moving has been cited in which publication?

... If you've heard the claim that a shark will drown if it stops moving, you probably know someone who reads "Ripley's Believe It or Not!"

Question 5 of 21

Sharks must remove _____ from the water around them in order to breathe.

... Sharks must remove oxygen from the water around them in order to breathe. They do this by taking in water through their mouths.

Question 6 of 21

Which part of the shark's body is responsible for absorbing oxygen from the water it takes in?

... Inside the gills of a shark are hundreds of gill filaments. Each filament has thousands of lamellae, or flaps, which contain blood vessels that absorb the oxygen from the incoming water.

Question 7 of 21

How many gill slits does a shark have?

... Depending on the species, sharks have five to seven pairs of gill slits. After extracting the oxygen from the water it takes in, the excess water flows back out of the shark's body through its gill slits.

Question 8 of 21

Sharks can extract about _____ percent of oxygen out of the 1 percent of oxygen that's present in the water.

... Sharks can extract about 80 percent of oxygen out of the 1 percent of oxygen that's present in the water it takes in. A shark constantly needs to be taking in water to ensure a steady flow of oxygen.

Question 9 of 21

Which of the following shark species don't swim at all?

... Some species of sharks, like angel sharks and nurse sharks, don't seem to swim at all.

Question 10 of 21

Buccal pumping is the process through which sharks pump water through their mouth and over their gills. Which shark species use this method to breathe?

... Many sharks breathe using the buccal pumping method, such as nurse sharks, angel sharks and carpet sharks. These species, many of them basically non-swimmers, spend much of their time lying on the bottom of the ocean floor.

Question 11 of 21

Sharks that buccal breathe usually have strong _____ muscles.

... Many of the sharks that buccal breathe are squashed along the length of their back, but have strong muscles in the face.

Question 12 of 21

The spiracle is a tube behind the eyes of a shark. The spiracle functions like a:

... When a shark lies at the bottom of the ocean floor and can't breathe through its mouth, the spiracle acts like a mouth by pulling in water. The water then exits through the gill slits.

Question 13 of 21

_____ ventilation is the breathing method sharks use to take in water while swimming.

... A more efficient method for a shark to take in water than buccal breathing is taking in water while swimming, known as ram ventilation because the water is rammed into the shark's mouth.

Question 14 of 21

Buccal pumping and ram ventilation are two methods sharks use to breathe. Most sharks can:

... Most sharks can switch back and forth between buccal pumping and ram ventilation. When they swim fast enough to force the water in more quickly than they can pump it, they switch to ram ventilation.

Question 15 of 21

Sharks that have lost the ability to breathe by buccal pumping and must keep moving to breathe are called obligate ram:

... Obligate ram breathers or ventilators have lost the ability to breathe by buccal pumping and will drown if they stop swimming and ramming water.

Question 16 of 21

Which of the following species of shark must keep moving to breathe?

... The shark species that must keep moving to breathe include the great white, the mako, the whale and the salmon shark.

Question 17 of 21

How many shark species must keep swimming in order to breathe?

... About two dozen of the 400 known shark species must keep swimming in order to breathe.

Question 18 of 21

In a study of lemon sharks, young sharks breathed _____percent more efficiently when swimming than when resting.

... According to Morrissey and Gruber, young lemon sharks breathed 6 percent more efficiently when swimming than when resting, even when resting so that the current allowed the water to flow directly into their mouths.

Question 19 of 21

Which part of the shark's body is responsible for coordinating its swimming?

... In an experiment with a small shark, the spiny dogfish, researchers found that swimming in sharks is coordinated by the spinal cord and not by the brain, so sharks may be able to turn off their brain and rest while still swimming.

Question 20 of 21

Reef sharks are usually:

... Under certain conditions, where the surrounding waters have an extremely high amount of oxygen and reduced salinity, even obligate ram ventilators like the reef shark may be able to stop moving and still keep breathing.

Question 21 of 21

Shark finning is a process whereby a shark's fin is:

... Shark finning is a process whereby a shark's fin is cut off and the shark is thrown back into the ocean, sometimes still alive. Finning usually results in the shark's eventual drowning.