Question

Some amphibians never leave the water, whereas others can survive in relatively dry terrestrial environments. Contrast the adaptations that facilitate these two lifestyles.

Short answer

Amphibians are organisms that have adapted to life in a moist environment or water. The amphibians that live in water have gills, aquaporins to absorb water, and fins for locomotion. Dry terrestrial amphibians have lungs in the place of gills and limbs to locomote.

Step-by-step solution

Amphibians

Amphibians are cold-blooded vertebrates that have four legs in their adult stage. These organisms have smooth, slimy skin, exhibit external fertilization, and have a complex life cycle.

Amphibians living in dry or wetland

Specific adaptations developed in the amphibians can help them to live on land or dry terrestrial environments. Lungs have replaced the internal gills of the organism. The development of eyelids enhances protection and vision. The skin has adapted to minimize water loss.

The amphibians living in the water have gills. They have a water protein channel called aquaporin. It helps in the absorption of water and reabsorption of diluted urine.

Adaptation that facilitates a dry and wet environment

When an amphibian is in an aquatic environment, oxygen is facilitated through the gills present in the skin. Their skin has special protein channels to enable water absorption and reabsorption of diluted urine.

An amphibian found on dryland has lungs in the place of gills for breathing. Legs and a tail are also special features found in land amphibians.