<span>The structure of the feet and legs varies greatly among frog species, depending in part on whether they live primarily on the ground, in water, in trees or in burrows. Frogs must be able to move quickly through their environment to catch prey and escape predators, and numerous adaptations help them to do so. Most frogs are either proficient at jumping or are descended from ancestors that were, with much of the musculoskeletal morphology modified for this purpose. The tibia, fibula, and tarsals have been fused into a single, strong bone, as have the radius and ulna in the fore limbs (which must absorb the impact on landing). The metatarsals have become elongated to add to the leg length and allow the frog to push against the ground for a longer period on take-off. The illium has elongated and formed a mobile joint with the sacrum which, in specialist jumpers such as ranids and hylids, functions as an additional limb joint to further power the leaps. The tail vertebrae have fused into a urostyle which is retracted inside the pelvis. This enables the force to be transferred from the legs to the body during a leap </span>
<span>The muscular system has been similarly modified. The hind limbs of ancestral frogs presumably contained pairs of muscles which would act in opposition (one muscle to flex the knee, a different muscle to extend it), as is seen in most other limbed animals. However, in modern frogs, almost all muscles have been modified to contribute to the action of jumping, with only a few small muscles remaining to bring the limb back to the starting position and maintain posture. The muscles have also been greatly enlarged, with the main leg muscles accounting for over 17% of the total mass of the frog.</span>
The answer is isometric training. To simplify, the strength gains with isometric training are specific to the angle of muscle contraction. In addition, Isometric exercise or isometrics are a kind of strong physical activity in which the joint angle and muscle length do not alter throughout contraction likened to concentric or eccentric contractions or as called as dynamic or as isotonic activities.
Answer:
Dissociation of actin subunits occurs.
Explanation:
When we add phalloidin to a solution containing G-actin, the phalloidin binds to actin filaments more tightly as compared to actin monomers which leads to a decrease in the constant rate of dissociation of actin subunits from the ends of the filament. This dissociation stabilizes the actin filaments through the prevention of filament depolymerization. So we can conclude that addition of phalloidin to actin leads to stabilizing of actin filaments.
The correct answer is: D. damage to nerves that control the stomach.
The vagus nerve is a cranial nerve that controls stomach contractions and thus, the movement of the food. When the vagus nerve is damaged, the muscles of the stomach do not function properly, so gastroparesis occur. Consequently, food then moves slowly or even totally stops moving through the digestive tract.