Question

Which statement about motor neurons is NOT correct? motor neuron pools innervating two different muscles, such as biceps and triceps, have separate non- overlapping locations in the ventral gray matter arranged in longitudinal columns motoneurons in a motor pool are recruited (activated) in rank order according to their size, from small to large small a-motor neurons tepd to innervate a large number of thick, pale muscle fibers that generate large forces but fatigue quickly an equal synaptic current will elicit a larger EPSP in a small than large motoneuron because smaller motoneurons have higher input resistance resistance Question 29 1 pts While driving a car, which brain region prepares you to move your foot from the accelerator to the brake pedal as you approach a traffic light that turns yellow? primary motor cortex primary somatosensory cortex hippocampus lateral premotor cortex cerebellum

Answer 1

Motor neurons in motor pool in every individual innervate only one muscle, whereas, muscle fiber in each individual innervate by one motor neuron.

And in case of one motor neuron has ability to innervate many muscle fibers.

Motor pools are classified in different categories of motor neurons.

Henneman's size principle defines the size of motor neuron, the activation is higher the contraction of muscle will be stronger, motor neuron are activated according to their order of smallest motor neurons to largest motor neurons that is slow to high force.

Small $\alpha$ - motor neurons activate very few muscle fibers and small forces are generated whereas, large motor neurons innervate larger and large force are generated.

Excitatory postsynaptic potential in interneurons gets evoke and respond to single potential action in presynaptic.

Slow activation of membrane depolarization if leads to continue for more seconds to minute after the termination results to neurotransmitter from presynaptic terminal which slows the ESPs.

This makes the option b correct.

29.While driving left turn is performed by posterior brain region whereas left turn with traffic activates multiple bilateral region mid posterior area of brain is activated.

Larger significant activation in which the condition is observed in multiple bilateral regions in mid-posterior brain, which includes premotor area and motor, vision, parietal, and the important role is played by cerebellum, somto sensory region during traffic.

Therefore, during driving the car cerebellum prepares or get activated to move foot from accelarator to brake pedal when traffic turns yellow.