Answer:
Histamine is a protein produced by <u>mast cells</u> in the body. It plays a very important role in the immune system of the body. Histamine is released in the body when <u>affected by an allergen</u>, e.g, pollen or animal dander. The immune system of the body will respond to such allergen by <u>making more mucus in the nose by releasing histamine</u>. There will be sneezing, itching, coughing and runny nose in response. This is a <u>basic defense of the body's immune system</u> to not enter any particle inside the body.
The valence electrons are shared between the atoms
Answer:
A. O, S, Se
Explanation:
They are all considered "other nonmetals," found in row 16 of the periodic table, and are chalcogens. The other options don't have as much in common.
Explanation:
I think option 3..............
Answer: If you change the number of electrons in an atom it will become an ion
Explanation: When you change the number of protons in an atom, you will change the atom from one element to a different element. Sometimes, when you add a proton to an element, the element will become radioactive. If you change the number of electrons in an atom, you will get an ion of the element.
