Several Key Factors Help to Determine the Types and Numbers

question 36

Multiple Choice

Several key factors help to determine the types and numbers of organisms found in the various layers of both freshwater and marine systems.What is not one of these?

• A) algal bloom
• B) availability of nutrients
• C) temperature
• D) dissolved oxygen levels
• E) availability of food

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Definitions:

Tyrosine

An amino acid that is important for protein synthesis and is a precursor to several significant hormones and neurotransmitters.

Iodine Atoms

Fundamental units of the chemical element iodine, essential for thyroid hormone production in living organisms.

Exocrine Function

The activity of exocrine glands that release their secretions through ducts to the exterior of the body or into a body cavity.

Endocrine Function

The activity of glands that secrete hormones directly into the bloodstream, regulating diverse bodily functions.