Describe the structure and function of the forelimbs and hind limbs of the frog.
The Correct Answer and Explanation is :
Structure and Function of Frog Forelimbs and Hind Limbs
Frogs have two pairs of limbs—forelimbs and hind limbs—that are adapted for their semi-aquatic and amphibious lifestyle. Each limb has a distinct structure and function suited to locomotion, support, and other activities.
Forelimbs
- Structure: The forelimbs are shorter and less robust than the hind limbs. Each forelimb consists of an upper arm (humerus), a lower arm (radius and ulna fused as the radioulna), and a hand with four fingers. The forelimbs are connected to the pectoral girdle.
- Function: The primary role of the forelimbs is to support the body when the frog is at rest and assist in landing during jumping. They also help in grasping objects and provide balance when the frog is stationary or moving.
Hind Limbs
- Structure: The hind limbs are longer and more muscular, consisting of a thigh (femur), a lower leg (tibia and fibula fused as the tibiofibula), and a foot with five toes. The hind limbs are connected to the pelvic girdle and include webbed toes to aid in swimming.
- Function: Hind limbs are adapted for powerful jumping and swimming. The long bones and strong muscles generate the force needed for leaping, while the webbed toes provide efficient propulsion in water.
Explanation
The contrasting designs of the forelimbs and hind limbs reflect their specialized roles. Frogs rely heavily on their hind limbs for movement. The long, muscular hind limbs enable them to leap great distances on land, a key survival strategy for escaping predators and catching prey. In water, the webbed toes act like paddles, facilitating swift swimming.
Meanwhile, the forelimbs absorb the impact of landing after a jump, preventing injury. They also help maintain balance and support the frog’s weight when at rest. Together, these adaptations make frogs highly versatile in both aquatic and terrestrial environments, demonstrating the evolutionary significance of their limb structure.