A motor unit is made up of a motor neuron and the skeletal muscle fibers innervated by that motor neuron's axonal terminals.roups of motor units often work together to coordinate the contractions of a single muscle; all of the motor units within a muscle are considered a motor pool. All muscle fibers in a motor unit are of the same fiber type.
SURFACE STRUCTURE. Basaltic lava flows erupt primarily from shield volcanoes, fissure systems, scoria cones, and spatter cones. These fluid lava flows can be subdivided into two end-member structural types, based primarily on the nature of lava flow surfaces: 1  Pahoehoe Lava -- Surfaces are smooth, billowy, or ropy.
A shield volcano is most likely to form during a lava flow of fluid basaltic material, usually those that flow down from either a flank fissure system or the summit itself.The most common type of shield volcano is those that form during one long-term eruption. shield volcano is most likely to form during a lava flow of fluid basaltic material, usually those that flow down from either a flank fissure system or the summit itself.