Iron (As Fe²⁺)is

question 11

Multiple Choice

Iron (as Fe²⁺) is

• A)toxic at all concentrations.
• B)safe at all concentrations.
• C)toxic at high concentrations, essential at low concentration.
• D)toxic at high concentration, not known to be essential.

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Definitions:

Complement

A system of small proteins found in the blood that assists the immune system in destroying pathogens.

Community Immunity

Also known as herd immunity, it is the resistance to the spread of a contagious disease within a population that results if a sufficiently high proportion of individuals are immune to the disease, especially through vaccination.

Type A Blood

A blood group within the ABO system characterized by the presence of A antigens and anti-B antibodies in the plasma.

Antibodies

Antibodies are protein molecules produced by the immune system in response to foreign substances, helping to fight off infections.