Answer: A
Explanation: Vaccines create memory cells with a weak version of the pathogen, so when they meet that pathogen again the body can respond more quickly and more efficiently since they have already been exposed to the pathogen.
Answer:
Electric current – The net movement of electric charges in a single direction through a wire or conductor. Voltage difference – The force that causes electric charges to flow; charges flow from high voltage to low voltage
Explanation:
They have an equal number of protons (positive charge) and electrons (negative charge)
Nervous tissue. Hope this helps!
