Atomic number shows the number of protons in the nucleus of an atom.
Atomic weight shows the is an another term for atomic mass, which means <span>It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.</span>
Answer:
Innate immunity is a non-specific immune system which provides defence against any pathogenic microorganism in early stages. It includes physical barrier such as skin, chemical barriers such as saliva, tears, et cetera, phagocytic cells such as macrophages, et cetera.
Acquired immune system is the one which develops after exposure to pathogen or antigen. It is highly specific in nature. It includes B-lymphocytes and T-lymphocytes. It includes the production of antibodies.
Vaccines are used to develop acquired immunity in people. The process is termed as vaccination or immunisation. Heat-killed or weakened pathogen or antigen is inserted into a person after which a person develops antibodies and memory cells against that pathogen or disease. So, the immune system acts more vigorously against that pathogen in secondary infection.
Thus, a person becomes immunised.
Answer:
Radioactive dating uses radioactive elements to date matter such as rocks and fossils. As the radioactive elements disintegrate, they turn into other elements. Scientist then use the ratio of the two elements to determine how old something is.
Explanation:
Carbon Monoxide has 2 atoms total - one atom of carbon (C) and one atom of oxygen (O) chemical formula is CO
Ethylene has 6 atoms total, 2 atoms of carbon (C) and 4 atoms of hydrogen (H), chemical formula is C2H4.
Ethylene has four more atoms than carbon monoxide (6-2) = 4