The Oceans Can Be Divided into Life Zones Even Though

question 147

Multiple Choice

The oceans can be divided into life zones even though they are all connected because

• A) the rate of photosynthesis is low in the oceans.
• B) ocean currents keep organisms close to where they were born.
• C) light penetration, and hence photosynthesis, vary with depth and determine where organisms live.
• D) trade winds keep warm and cold waters separate.
• E) continents provide barriers to movement of planktonic life forms.

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Definitions:

Unmyelinated Axons

Refer to nerve fibers that lack a myelin sheath, resulting in slower transmission of nerve impulses compared to myelinated axons.

Gray Matter

The regions of the brain and spinal cord that consist primarily of neuronal cell bodies and are involved in muscle control and sensory perception.

Interneurons

Neurons that are neither afferent nor efferent, but instead carry information from one neuron to another.

Myelin Layers

Myelin layers are protective coverings made of fatty substances that surround the axons of some neurons, facilitating the rapid transmission of electrical impulses along nerve cells.