Introduction to Amphibia

The ulna and radius bones in the forearm are fused together, forming a single structure.

The tibia and fibula bones in the lower leg are fused together, forming a single structure.

Frogs lack ribs and a diaphragm, so they breathe differently compared to mammals.

The frog's long and sticky tongue, extended from the mouth, helps catch prey.

A common opening in amphibians for excretory, reproductive, and digestive systems.

Frogs have a three-chambered heart with two atria and one ventricle.

Frogs have two types of circulation: pulmonary (to lungs) and systemic (to the body).

Frogs have relatively inefficient lungs, so they also breathe through their moist skin.

Amphibians are vertebrates that evolved from lobe-finned fishes around 370 million years ago and are the first animals to live on land.

Amphibians live in water during their larval stage, usually as tadpoles, and transition to living on land as adults. This means they experience two distinct phases in their life.

Amphibians lack the amnion, a protective membrane that surrounds the developing embryo in amniotes. Their eggs are laid in water and lack the protective shell found in amniotes.

Amphibians are tetrapods, which means they possess four limbs. These limbs allow them to move on land, unlike their fish ancestors.

Amphibians breathe through gills during their larval stage and develop lungs for breathing air as adults. This is a significant adaptation for life on land.

Amphibians have smooth, wet skin that is permeable to water. Their skin helps them breathe and can even be poisonous in some species. They lack scales or feathers.

Amphibians are cold-blooded, which means they rely on external sources of heat to regulate their body temperature. They are also known as ectothermic.

Amphibians possess a cloaca, a single opening that serves as the exit for waste products, reproductive fluids, and eggs.

The main control center of the nervous system in amphibians, responsible for processing information and regulating bodily functions.

A sensory organ located in the mouth of amphibians that detects chemicals in the environment, enhancing their sense of smell and taste.

A transparent eyelid that protects the eye and keeps it moist in amphibians.

A sensory system present in amphibian larvae (tadpoles) that detects water movements and vibrations, helping them navigate in aquatic environments.

A type of kidney found in amphibians, responsible for filtering waste products from the blood.

A sensory organ found in some amphibians, particularly frogs, that detects chemical cues in the environment, aiding in prey detection and social interactions.

A sensory appendage located on the head of caecilians, a group of limbless amphibians. It helps them detect chemical cues in the environment and navigate in the dark.

A reproductive strategy common in many amphibians where eggs are fertilized outside the body. The male typically releases sperm onto the eggs as they are laid by the female.

A reproductive strategy where fertilization occurs inside the female's body before eggs are laid. The male deposits sperm inside the female, and the eggs are fertilized internally.

The distinct developmental path of many amphibians, starting as a tadpole and transitioning into an adult form, characterized by significant structural and physiological changes.

An order of amphibians characterized by tailless bodies and prominent hind legs, adapted for jumping. Examples include frogs and toads.

The process by which an organism reproduces while still in its larval or juvenile stage, eliminating a distinct adult phase.

The production of offspring by an organism in its larval or juvenile form, eliminating the adult phase of the life cycle.

Salamanders, newts, and other elongated amphibians with tails. Their bodies are often slender, and they have smooth, moist skin.

A state of inactivity and reduced metabolic rate in cold-blooded animals during winter or periods of unfavorable conditions.

The sum of all chemical processes that occur within a living organism to maintain life.

Animals that regulate their body temperature internally, using metabolic processes to maintain a relatively stable internal temperature.

The ability of an animal to switch between homeothermic and poikilothermic temperature regulation, depending on environmental conditions.