A concentration gradient is a process of particles, which are sometimes called solutes, moving through a solution or gas from an area with a higher number of particles to an area with a lower number of particles. The areas are separated by a membrane.
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Answer: Photosynthesis is important to living organisms because it is the number one source of oxygen in the atmosphere.
Explanation: chloroplasts photosynthesis uses carbon dioxide and water to assemble carbohydrate molecules (usually glucose) and releases oxygen into the air
Answer: The answer is (4), centuries
Explanation:
A jet stream forms high in the upper troposphere between two air masses<span> of very different temperature. The greater the temperature difference between the air masses, the faster the wind blows in the jet stream.
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So "Differences in temperature between two air masses" is the answer
A memory B cell is kinda of how it sounds it has a memory of what your body has fought before such as a virus and can stimulate a response quicker then the first time you encountered it.
If you lack memory B cells your body doesn't built up the same immune response when you come into contact with the virus again.
"Vaccination would prevent further disease" Incorrect, a vaccine lets you build up memory cells to combat the disease if you lack them you cannot build up a defense.
"Vaccination would not prevent further disease" Correct, a vaccine can be a dead version of a virus or parts of a virus that shows your body what to respond to quickly in the future. If you body cannot make memory b cells it wouldn't help to use a vaccine. Your body wouldn't keep a memory of it being bad.
"You would not produce antibodies" Even if your body does not remember a particular virus it does produce antibodies to combat it just not as quick or efficiantly as something it has come into contact with before and produced memory cells.
"You would over produce histamine" Incorrect, different process for that histamine.