Pretest-posttest designs grew from the simpler posttest only designs, and address some of the issues arising with assignment bias and the allocation of participants to groups. One example is education, where researchers want to monitor the effect of a new teaching method upon groups of children.
The neuromuscular junction (NMJ) is the site of communication between motor nerve axons and muscle fibres.It is composed of four specialised cell types: motor neurons, Schwann cells, muscle fibres and the recently discovered kranocytes.he neuromuscular junction (NMJ) is the site of communication between motor nerve axons and muscle fibres.
Synapses and neuromuscular junctions are physiologically the same, however, the neuromuscular junction is a specific type of synapse that occurs between motor neuron and muscle fiber. At other places in the body, such as the Central Nervous System, the structure with similar role is known as synapse.