Answer:
The levels, from smallest to largest, are: molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere.
Explanation:
Gonadotropin-releasing hormone, luteinizing hormone (LH for short) and follicle-stimulating hormone (FSH for short).
EXPLANATION
When your body reaches a certain age, your brain releases a special hormone that starts the changes of puberty. It's called gonadotropin-releasing hormone, or GnRH for short. When this hormone reaches the pituitary gland, it releases two more hormones into the bloodstream: the LH and FSH. Although boys and girls do have these hormones, it depends on their sexual orientation the way these hormones work.
Antibodies are produced when the body is exposed to antigens.
During an initial encounter with a foreign antigen, the body's immune system namely the adaptive arm of the immune system, produces memory cells, a group of special lymphocytes that retain and store memory of the antigen.
On a second encounter with the same kind of antigen, the immune system "remembers" the antigen and mounts a rapid, specific and vigorous immune response against the antigen. This response includes the production of massive amounts of antibodies very specific to the antigen.
The antibodies effectively neutralize the antigen and facilitate its destruction.