Filip, aged 64, was recently diagnosed with Alzheimer's. His medical reports will most likely reveal a diminished production of Multiple Choice

dopamine.
gamma aminobutyric acid.
serotonin.
acetylcholine.

Filip's medical report, diagnosed with Alzhaimer's, may reveal a diminished production of acethylcholine.

Explanation:

Alzhaimer's disease is a neurodegenerative condition that causes immediate memory loss, behavioral changes and cognitive impairment, due to neuronal alterations and atrophy.

The neurotransmitter acetylcholine —related to neuronal transmission and body movement— may experience a decrease in its production leading to Alzheimer's, according to the cholinergic hypothesis.

Many therapies and treatments at present are based on the use of drugs to correct the acetylcholine deficit.

Regarding other options:

format change of dna.  

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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