Trace Elements Are Those Required by an Organism in Only

question 42

Multiple Choice

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates, but not by other organisms such as bacteria or plants?

• A) nitrogen
• B) calcium
• C) iodine
• D) sodium
• E) phosphorus

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Definitions:

Memory Map

A schematic detailing the allocation of system memory to various functions and programs, used in programming and system design for resource management.

Normally Open

Describes a switch or relay contact that is open (disconnected) in its resting state and closes (connects) when activated.

XIC Instruction

A "Examine if Closed" instruction in PLC programming, used to check if a specific condition or input is true.