Fishes Flashcards
What are the main functions of these different fins?
Paired fins:
Pectoral -help provide lift for animal,
Pelvic – protect the claspers;
Unpaired fins:
Dorsal- provide stability
Anal- also provide stability and help the water flow across the shark
Caudal (Tail)- can be heterocercal , meaning different lengths from top part and bottom
How are chondrichthyes different from bony fish? What kinds of fish are found in class chondrichthyes
They have cartilage instead of bones; Sharks and rays
What is meant when the tail is described as heterocercal?
it means different lengths from the top of the tail to the bottom
What is a nictitating membrane?
it’s protective tissues the covers the eyes of sharks, similar to eyelids
What kind of scales do sharks have
placord scales : dermal denticles, they are like teeth
How can male and female sharks be distinguished?
Males have claspers and females just have slits
How do sharks osmoregulate?
they are isotonic and remain by keeping high concentrations of urea in blood
How do sharks breathe?
they have use gills to pass water over and pull out the o2
Do all sharks need to swim in order to breath?
No, some sharks can pump water over their gills
what is ram ventilation?
when the sharks have to swim in order to pass water over gills to breathe
how do rays breathe
using gills on under side
How do sharks stay afloat?
they have large livers that are packed with lipids and some can swallow air to help with buoyancy. They have to constantly move in order to stay afloat.
What is meant by the terms: oviparous, ovoviviparous and viviparous? What provides the nutrition to the developing embryo in each of these strategies?
Oviparous – eggs left out in environment
Ovoviviparous- eggs are carried in mother and hatch in mother
Viviparous- placental nutrition and live births
How do sharks use their senses to track prey at different distances?
They have a really good since of smell eye sight. They have Ampullae of Lorenzini, which allow them to detect bio electric impulses at close ranges and can sense vibrations using lateral lines
What are the ampullae of Lorenzini and where are they located?
electroreceptors on the sharks head
What do elasmobranchs use electroreception for?
to find prey buried in the sea floor
Which species of shark are considered to be the most dangerous for man?
the bull shark
Describe the two living groups of jawless fishes
Hagfish: live in cold water and dig burrows in mud, produce slime from mucus glands
Lampreys: primarily freshwater, marine species live in ocean but breed in rivers
What are the threats to sharks? What is shark finning? What are the fins used for? What happens to the rest of the shark?
By catch and shark finning; when fisher catch sharks cut off their fins and throw the rest back in the water; are eaten and taken as trophies
How are bony fish different from cartilaginous fish? What adaptations are seen in bony fish that are absent in cartilaginous fishes?
True bone in skeleton, flatend scales
Swim bladders, help them stay afloat without swimming , Pectoral fins are used for more functions, Operculum- covers the gills and help pull and push out water of gills
What are the two lineages of bony fish? What is the single marine example of sarcopterygii?
Actinopterygii: Ray Finned Fishes
Sarcopterygii: Lobe finned fishes
Describe how the body shape of certain bony fish is adaptive to their habitats or lifestyles.
You can tell if they are fast swimmers or floats if their bodies are more stream lined or more bulgy
How do bony fish stay afloat? How is this different from how cartilaginous fish stay afloat?
They have swim bladders that the can fill with air to stay afloat. Cartilaginous fish have to stay moving or they will sink
What are the features of fast swimming fish? How can you tell by looking at a fish if it is a fast swimmer?
The caudal shape will tell you if the fish is fast. If it has a lunate shaped tail fin they are fast swimmers
