Tundra. The tundra is a treeless polar desert found in the high latitudes in the polar regions, primarily in Alaska, Canada, Russia, Greenland, Iceland, and Scandinavia, as well as sub-Antarctic islands.
The muscles acting on the foot can be divided into two distinct groups; extrinsic and intrinsic muscles. 1  The extrinsic muscles arise from the anterior, posterior and lateral compartments of the leg.2  They are mainly responsible for actions such as eversion, inversion, plantarflexion and dorsiflexion of the foot. The extrinsic muscles arise from the anterior, posterior and lateral compartments of the leg. 2  They are mainly responsible for actions such as eversion, inversion, plantarflexion and dorsiflexion of the foot.
Reflexes help to maintain proper muscle tone, balance, and responsiveness of the legs and feet to stimuli such as stepping on a sharp object. The nerves of the leg and foot arise from spinal nerves connected to the spinal cord in the lower back and pelvis. As these nerves descend toward the thighs, they form two networks of crossed nerves known as the lumbar plexus and sacral plexus.