One characteristic of life is that living things have different levels of organization
-They have both molecular and cellular organization
- They must have the ability to organize simple substances into complex ones.
- They organize cells at several types of levels, namely:
(a) Tissue- a group of cells that perform a common function
(b) Organ - A group of tissues that perform a common function.
(c) Organ system- a group of organs that perform a common function.
(d) Organism- any complete living thing.
X, answer is X, good luck now, pls answer my question pls pls.
There are many answer you have to be specific
Because an antibody is "made" relative to the antigen, but kept at low levels when you are exposed the first time ("primary immune response"). The second time you're exposed to the same antigen, memory cells recognize it and the body produces a high level of antibodies, and the level of antibodies usually remains higher for a longer time ("secondary immune response"). This is your basic immune response (primary and secondary).
This explains exactly why vaccines are effective to extremely effective.
