pls help me with this immediately!!! and pls don’t guess and leave links only answer if u actually know. (i’ll be leaving brainiest to the correct person)

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

the answer is 1. photosynthesis. glad to

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

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