Question

What prevents two antagonistic muscles from contracting simultaneously? O Polysynaptic reflexes The myotatic reflex Muscle spindles Reciprocal inhibition QUESTION 2 Motor neurons communicate to muscle at the: neurofiber synapse muscle spindle polar junction neuromuscular junction

Answer 1

1. The correct answer is Option D. The reciprocal inhibition does not allow two antagonistic muscles from contracting directly.
2. The correct answer is Option D. The communication occurs at the neuromuscular junction.
3. The correct answer is Option A. Actin is responsible for initiating muscle contractions.
4. The correct answer is Option A. Myosin and actin, respectively.

Please post the other questions separately. As per our answering guidelines we are supposed to answer just one question or four sub parts of the same question.