Final answer:
Magnesemia refers to the level of magnesium in the blood. This condition affects the nervous system, muscles, and bone health, but doesn't have an 'opposite effect' on them. The question's options don't accurately answer it.
Step-by-step explanation:
The question pertains to the medical term 'magnesemia', which refers to the quantity of magnesium in the blood. The prefix 'magnes-' points to 'magnesium'. The expression 'the opposite of the prefix plus all what?' seems to imply the impact on numerous body systems rather than an exclusive one. Magnesemia manipulates neural and muscular functions and influences bone structure, yet it doesn't seem to have an 'opposite effect' on either. Therefore, none of the options a) Muscles b) Bones c) Nerves d) Blood cells precisely answer the question as posed.
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