Select the physical traits that apply to amphibians

Select the physical traits that apply to amphibians.

swim bladder

internal fertilization

three chambered heart

jointed limbs

aquatic reproduction

sense organs

lungs

The Correct Answer and Explanation is :

Correct Physical Traits of Amphibians:

1. Three-chambered heart
2. Jointed limbs
3. Aquatic reproduction
4. Sense organs
5. Lungs

Explanation:

Amphibians are a unique group of vertebrates that serve as a critical evolutionary link between aquatic and terrestrial life. Their physical traits reflect adaptations to both environments.

1. Three-chambered heart:
   Amphibians have a heart with three chambers—two atria and one ventricle. This structure allows for partial separation of oxygenated and deoxygenated blood, an adaptation that supports their dual life on land and in water. However, this system is less efficient than the four-chambered heart seen in birds and mammals.
2. Jointed limbs:
   Most amphibians have jointed limbs, which are an evolutionary adaptation for movement on land. These limbs provide support and enable activities like crawling, jumping, and climbing. For instance, frogs use their strong hind limbs for leaping, while salamanders crawl using all four limbs.
3. Aquatic reproduction:
   Amphibians generally reproduce in water or moist environments. They lay eggs that lack a protective shell, making them dependent on water to prevent desiccation. Most amphibians undergo external fertilization, where males fertilize eggs outside the female’s body.
4. Sense organs:
   Amphibians possess well-developed sensory organs to detect environmental cues. Their eyes are adapted for vision both underwater and on land, and they have tympanic membranes for hearing. Additionally, their sensitive skin helps them detect changes in humidity and temperature.
5. Lungs:
   Amphibians breathe through their lungs, skin, and sometimes gills, depending on their life stage. Adult amphibians use lungs for respiration, though many species also rely on their permeable skin for gas exchange.

Incorrect Traits:

• Swim bladder: This is found in fish for buoyancy control, not amphibians.
• Internal fertilization: Most amphibians rely on external fertilization, with few exceptions like some salamanders.

Amphibians’ adaptations highlight their transitional nature between aquatic and terrestrial ecosystems.