Lab 3 - Comparison of External Anatomy Flashcards
What does the term neotenic mean? Which animal has this?
Neotenic means that it has retention of traits only seen in juveniles. This is in mud puppies. They retain external gills and live in water for their whole life
What is a crepuscular lifestyle and who has this?
Active during twilight; the cat
What is the lifestyle of the spiny dogfish like? What is its scientific name?
Squalus acanthias. It is the most abundant shark species found all over the world. It will form schools of hundreds of individuals and an opportunistic feeder that will consume a variety of prey. Bottom-feeders.
What is the lifestyle of a mudpuppy like and what is its scientific name?
Necturus maculosus. It is a freshwater vertebrate found in eastern North America in lakes, rivers, and ponds. These nocturnal creatures are entirely aquatic and eat a variety of small organisms. They walk along bottom of the water and live in dark, murky water.
What features of the dogfish are important in locomotion?
Rostrum, dorsal fins, pelvic fins, pectoral fins, caudal fin
What type of caudal fin does a dogfish have?
Heterocercal
How does a shark swim?
It uses its caudal fin for propulsion and uses its dorsal fins for stabilization. Also, the pectoral fins help to steer it.
What are the respiratory features of a dogfish?
Spiracle, mouth, gill slits
How does a shark breathe?
As the shark moves, water enters through its mouth and leaves through the gill slits. In this process, the water is filtered for the oxygen.
What is the spiracle for?
The spiracle is found primarily in bottom-feeders, as it allows them …..
What are a shark’s digestive and urogenital features?
Mouth, teeth, cloaca, claspers, urogential/urinary papilla
Whats the difference between a urinary and urogenital papilla?
Only males have urogenital papilla, as it also carries the sperm
How are shark teeth different than mammals?
They are derived from the epidermis, like their placoid scales
Why aren’t the nares considered a respiratory structure?
Because they contain olfactory epithelia
What are sensory features in the shark?
Nares, eyes, eyelids, ampullae of Lorenzini, lateral line
