Aquatics - Species and classification

Livebearers are fish species that produce young by ___.

• Live birth.

• Egg laying.

Cichlid species can be tropical freshwater and tropical marine species.

• True.

• False.

Which classification of fish have specialised organs which allows them to breathe atmospheric air?

• Catfish and koi carp.

• Anabantids

• Cyprinids.

Tangs, Butterflyfish, and Damselfish are all species of what water condition?

• Temperate freshwater.

• Tropical freshwater.

• Tropical marine.

• Brackish.

Which classification of species have a cartilage structure?

• Cyprinids.

• Sharks, skates, and rays.

• Tetras, rasboras and danios.

• Chondrichthyes

Answer explanation

Only a Chondrichthyes (sharks, rays, skates, and some other species) teeth and vertebrae are calcified.

How do Chondrichthyes have an advantage with their unique structure?

• More flexible and fast.

• Less appetite and require less food.

• Better at disguising themselves in their habitat.

Agnatha fish are also referred to as ___less fish.

• Jawless.

• Finless.

• Boneless.

• Eyeless.

Answer explanation

Agnatha species are considered to be the earliest vertebrae.

What is the notochord in Agnatha species?

•  A long cord that runs throughout the body which picks up electrical signals.

• A unique part of the digestive system which provides no use anymore.

•  A flexible cord of cells that provides the body at the embryonic stage.

• A specialised tounge-like organ.

Which species of fish below is an example of a Osteichthyes?

• Mahi-mahi.

• Coelacanth.

• Oarfish.

• Arapaima.

Answer explanation

Osteichthyes are also referred to as bony fish.

What is unique about lungfish evolution?

• They evolved the ability to walk on land.

• They evolved to keep the ability to breathe oxygen from the surface.

• They evolved the ability to breathe in carbon dioxide safely.