Fish Adaptations

What body shape is optimized for cruising in pelagic zones?

Streamlined shape & strong caudal tail, as seen in tuna.

Which fish shape is more maneuverable in reef environments?

Disc-shaped, as seen in butterflyfish and parrotfish.

What adaptation allows bony fish to maintain neutral buoyancy?

Swim bladder.

How do cartilaginous fishes achieve buoyancy?

They have lighter cartilaginous skeletons and large oily livers.

What is the function of gill rakers?

They filter particles that may damage gills and can aid in feeding - important for filter-feeding sharks like whale sharks.

What process allows for efficient gas exchange in fish gills?

Counter-current gas exchange which enhances diffusion of oxygen from seawater into the bloodstream of fish.

What is ram ventilation in sharks?

A method where the animal must keep moving forward to maintain water flow over gills for respiration.

What is the role of the operculum in bony fish?

It covers the gills and enables active pumping of water over them.

What is osmoregulation in fish?

The process of maintaining osmotic balance for muscle control, nerve impulses, waste excretion, and nutrient absorption.

What is an osmoregulator?

An organism that actively maintains its internal osmotic potential different from its environment.

What does hypoosmotic mean in relation to bony fish?

They maintain a lower osmotic potential than their environment, typically fish in seawater.

What is the difference between ectotherms and endotherms?

Ectotherms have their temperature controlled by the environment, while endotherms regulate their temperature internally.

What is broadcast spawning?

The timed co-release of eggs and sperm into the water. Low parental investment.

What does hyperosmotic mean in relation to bony fish?

They maintain a higher osmotic potential than their environment, typically fish in fresh water.