Fishes Flashcards
What fins did fishes evolve?
Pectoral and pelvic fins
What did the fins do?
Paired fins gave fishes more control of body movement while the tail fin gave greater thrust when swimming
What are the two major groups of fishes?
Chondrichthyes
Osteichthyes
What are Chondrichthyes?
Modern sharks and rays; skeleton made of strong resilient cartilage
What are Osteichthyes?
Evolved fish with a skeleton made of bone
What steps does the food follow in the digestive tract of a shark?
- Mouth
- Pharynx
- Esophagus
- Stomach
- Pyloric ceca
- Pancreas/liver
- Intestine
- Anus
How to fish breathe?
They use their gills to exchange gasses by pulling oxygen rich water in through their mouths, pumping it over their gill filaments, and pushing oxygen poor water out through openings in the sides of the pharynx
How does blood circulate in a fish?
It goes in a single loop around the body from the heart to the gills, from the gills to the rest of the body and then back to the heart
What are the four parts of the heart?
Sinus venosus
Atrium
Ventricle
Bulbous arteriosis
What is the sinus venosus
A chamber that receives blood and forces it into the atrium
What is the atrium
Receives oxygen deprives blood from the sinus venosus
What is the function of that ventricle?
It pumps blood to the gills/lungs
What is the bulbous arteriosis?
Chamber that receives blood from the ventricle before heading throughout body through aorta
The kidneys of salt water fishes pump out concentrated urine
Low water content, high salt
The kidneys of fresh water fishes pump out dilute urine
High water content, low salt
What do the olfactory bulbs do?
They’re involved with the sense of smell or olfaction
What does the cerebrum do?
It’s responsible for all the voluntary activities but primarily processes the sense of smell
What does the optic lobe process?
Sight
What does the cerebellum do?
Coordinates body movement
What does the medulla oblongata do?
It controls the function of many inside organs
Starting with the weird diving path at the top, what order does everything go in the fish brain?
Olfactory bulbs Cerebrum Optic lobe Cerebellum Medulla oblongata
What do fish use the lateral line system for?
To sense the motion of other fishes/predators
What is the function of the swim bladder?
It’s full of gas and controls buoyancy
How do fish move?
They contract paired sets of muscles in either side of the backbone
What are agnathan fishes?
Jawless
Do jawless fishes have a bone or cartilage skeleton?
Cartilage
What are the two classes of jawless fishes?
Lamprey and hagfish
Fish whose embryos develop and hatch outside the mothers body
Oviparous
The eggs stay in the mothers body after internal fertilization and use the yolk from the egg for nourishment
Ovoviviparous
Ex: guppies
The eggs stay in the mothers body after internal fertilization and use the mothers body for nourishment
Viviparous (this species is born alive)
What is in the class chondrithyes?
Sharks Rays Skates Sawfish Chimaeras
Fish that spend most of their lives in the ocean. It migrate to fresh water to breed
Anadromous
Class sarcopterugii
Lobe-finned fishes are ancestors to the tetrapods and have lungs and gills
How many living species of bony fishes are not classified as ray-finned?
7
Example of class actinopterygii
Bichir
Atlantic sturgeon
Paddlefish
