What Causes a Decrease in Oxygen Levels Beyond the Sunlit

question 26

Multiple Choice

What causes a decrease in oxygen levels beyond the sunlit layer?

• A) The respiration from marine animals and bacteria
• B) The by-products of photosynthesis
• C) There are fewer animals present
• D) Decreased saturation because of cooler water

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Definitions:

Lewis Structure

A diagram that represents the bonds between atoms and the lone pairs of electrons in a compound.

Water

A chemical compound, H2O, essential for all known forms of life, characterized by its liquid state at room temperature and its ability to dissolve many substances.

Helium

Helium is a chemical element with symbol He and atomic number 2, known as the second lightest and second most abundant element in the observable universe, primarily used in cryogenics and as an inert gas shield in arc welding.

Lewis Structures

Diagrams that represent the valence electrons of atoms within a molecule, showing how they are bonded together.