<span>I think it's right, sorry if its not. ATP binding site Actin binding site</span>
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.
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
B I think because it would have to be 25% so then Aa would be appropriate as of it's recessive.
