biology10

Spawning

The process of fish releasing eggs and sperm into the water for external fertilization.

Cartilage

A flexible connective tissue found in fish skeletons, especially in sharks and rays.

Pineal eye

A light-sensitive organ found in some fish and amphibians.

Cloaca

A common cavity for the release of waste and reproductive materials.

Ovoviviparous

Producing eggs that hatch inside the female's body before birth.

Oviparous

Laying eggs that develop and hatch outside the mother’s body.

Viviparous

Giving birth to live young after internal development.

Gonad

An organ that produces gametes (testes in males, ovaries in females).

Anadromous

Fish that migrate from saltwater to freshwater to spawn.

Cleaning station

A location where fish gather to have parasites removed by cleaner fish or shrimp.

Tetrapod

A vertebrate with four limbs.

Extinct

A species that no longer exists.

Extant

A species that is still alive today.

Living fossil

A species that has remained unchanged for millions of years.

Spermatophore

A packet of sperm used by some animals for fertilization.

Aposematic coloration

Bright warning colors that signal toxicity to predators.

Mimicry

When one species resembles another for protection.

Swim bladder

A gas-filled organ in fish that helps regulate buoyancy.

Lateral line

A sensory system in fish that detects water movement and vibrations.

Agnathans

Jawless fish, such as lampreys and hagfish.

Chondrichthyes

Cartilaginous fish, including sharks, rays, and skates.

Ampullae of Lorenzini

Specialized electroreceptors in sharks that detect electrical signals from prey.

Heterocercal tail

A type of fish tail where the upper lobe is larger than the lower lobe, common in sharks.

Ray-finned fish (Actinopterygii)

Fish with fins supported by thin, bony rays (e.g., tuna, cod, seahorse).

Lobe-finned fish (Sarcopterygii)

Fish with fleshy, lobed fins (e.g., coelacanth, lungfish).

Anura

The amphibian order that includes frogs and toads.

Caudata

The amphibian order that includes salamanders and newts.

Gymnophiona

The amphibian order that includes caecilians (legless amphibians).

Tiktaalik

A fossil species believed to be a transitional form between fish and amphibians.