The ____ Causes Muscles to Contract or Relax and Glands

question 51

Multiple Choice

The ____ causes muscles to contract or relax and glands to secrete products.

• A) synaptic knob
• B) axon diameter
• C) neurotransmitter
• D) interneuron
• E) cell body

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Definitions:

Internal Environment

Refers to the conditions and processes within an organism or system, often maintained within certain limits to ensure functionality.

Bilateral Body Plans

Symmetrical body plans in animals that have a distinct left and right side, along with a front and back.

Cephalization

The evolutionary trend towards concentrating sensory and neural organs at the anterior end of an organism.

Nerve Nets

Simplest form of a nervous system found in invertebrates, consisting of a network of interconnected nerve fibers.