Organization of the Nervous System & Neuron Structure

Forty question-and-answer flashcards reviewing the lecture’s key points on nervous system organization, the roles of sensory and motor divisions, distinctions between somatic and autonomic control, and the structure and function of neurons and glial cells.

Into which two primary groups is the human nervous system traditionally divided?

The central nervous system (CNS) and the peripheral nervous system (PNS).

Which major part of the nervous system is made up mainly of nerves found outside the brain and spinal cord?

The peripheral nervous system (PNS).

In the highway analogy, which division of the PNS is compared to the northbound lanes?

The sensory (afferent) division.

Sensory (afferent) signals travel in which direction?

From the body toward the brain.

Name two senses mentioned in the lecture whose signals use the sensory division.

Touch and smell.

Which division of the PNS is likened to the southbound lanes of a highway?

The motor (efferent) division.

Motor (efferent) signals travel in which direction?

From the brain to the body.

What is the voluntary branch of the motor division that controls skeletal muscles called?

The somatic nervous system.

What is the involuntary branch of the motor division that automatically regulates organs called?

The autonomic nervous system.

Which motor branch allows you to decide to raise your hand?

The somatic nervous system.

Which motor branch controls heart rate and hormone secretion without conscious control?

The autonomic nervous system.

During which course unit will all of the senses be covered, according to the roadmap?

Unit 2 (the sensory division unit).

Which portion of the motor system (somatic or autonomic) is mostly taught in A&P I with the neuromuscular junction?

The somatic nervous system.

Which type of nervous-tissue cell is described as the “star” that communicates and processes information?

The neuron.

What family name is used for the supportive cells of nervous tissue?

Glial cells (glia).

What is the central region of a neuron that contains the nucleus called?

The cell body (soma).

Which neuron structures look like tree branches and receive incoming information?

Dendrites.

The word “dendrite” is based on a Greek root meaning what?

Tree.

What is the long projection of a neuron that transmits outgoing signals called?

The axon.

What insulating material wraps many axons and was compared to bubble wrap?

Myelin.

What wave-like process carries messages down an axon?

Propagation of an action potential.

Name a neurological disease in which myelin is lost, leading to tremors and other issues.

Multiple sclerosis (a demyelinating disease).

Relative to the cell body, in which direction do dendrites conduct electrical information?

Toward the cell body.

Relative to the cell body, in which direction does an axon conduct electrical information?

Away from the cell body.

Which part of the neuron did the instructor call the “input end”?

The dendrite side.

Which part of the neuron did the instructor call the “transmitting side”?

The axon.

Do glial cells primarily send long-distance electrical signals like neurons?

No; they mainly provide support, insulation, and homeostatic functions.

Are actions of the somatic nervous system voluntary or involuntary?

Voluntary.

Are actions of the autonomic nervous system voluntary or involuntary?

Involuntary.

Can you consciously stop the body from producing aldosterone, according to the lecture?

No; endocrine control is autonomic and involuntary.

Which division of the nervous system sends commands to both muscles and internal organs?

The motor (efferent) division of the PNS.

What colorful phrase did the instructor use to describe the microscopic appearance of a neuron?

“A big splashy splatter starburst thing.”

Which tissue is easy to identify histologically because neurons look so distinctive?

Nervous tissue.

What technical terms describe signals traveling toward the CNS and away from the CNS, respectively?

Afferent (sensory) and efferent (motor).

Give two general functions commonly performed by glial cells.

Providing structural support and electrical insulation (other acceptable answers: nourishment, waste removal, homeostasis).

Approximately what percentage of the course content is covered before the practice exam day, according to the roadmap?

About 60%.

What classroom demonstration was used to model the wave-like spread of an action potential down an axon?

A stadium-style human wave performed by the students.

What happens to neural communication when myelin erodes, according to the lecture?

Signals short-circuit, leading to tremors and other neurological problems.

Which branch of the motor division automatically controls smooth muscle, cardiac muscle, and glands?

The autonomic nervous system.

True or False: The sensory and motor divisions are completely separate with no interaction.

False; the division is a teaching simplification and the systems interact.

Which structural feature at the very beginning of the axon initiates the action potential?

The axon hillock (initial segment).