Chapter 10 Nervous system

What are the two main divisions of the nervous system?

Central Nervous System (CNS) and Peripheral Nervous System (PNS).

What are the major features of a neuron?

Neurons consist of a cell body, dendrites, and an axon.

Name the three types of neurons based on the direction they convey impulses.

Sensory neurons (afferent), Motor neurons (efferent), and Interneurons.

How do glia differ from neurons?

Glia are support cells that do not conduct impulses, while neurons are specialized for impulse conduction.

What are three types of glia?

Astrocytes, Microglia, and Oligodendrocytes.

What is the function of the sensory neurons?

Sensory neurons conduct impulses from the body to the spinal cord and brain.

What is the role of motor neurons?

Motor neurons conduct impulses from the brain and spinal cord to muscles and glands.

What is a reflex arc?

A reflex arc is the simplest neural pathway which allows for a reflex action, conducting impulses in one direction.

What are the main components of a reflex arc?

Sensory neuron, interneuron (in more complex arcs), and motor neuron.

What is myelin and what does it do?

Myelin is a fatty substance that insulates nerve fibers, increasing the speed of nerve impulse conduction.

Describe saltatory conduction.

Saltatory conduction is when nerve impulses jump from one gap in the myelin sheath to another, speeding up transmission.

What is a synapse?

A synapse is the junction where impulses are transmitted from one neuron to another.

How do neurotransmitters function in the nervous system?

Neurotransmitters are chemicals released at synapses that bind to receptors on postsynaptic neurons, stimulating impulse transmission.

Name one neurotransmitter and its primary role.

Acetylcholine, which is involved in muscle contraction at neuromuscular junctions.

What is the difference between white matter and gray matter in the nervous system?

White matter consists mainly of myelinated axons, while gray matter consists mainly of neuronal cell bodies and unmyelinated fibers.

What are cranial nerves?

Cranial nerves are 12 pairs of nerves that connect the brain to structures in the head, neck, and body.

What is the peripheral nervous system?

The peripheral nervous system consists of the nerves connecting the brain and spinal cord to other parts of the body.

What is an effector in the context of a reflex arc?

An effector is an organ that carries out a response to a neural stimulus, typically muscle or gland.

What does 'dermatome' refer to?

A dermatome is an area of skin supplied by a single spinal nerve.

What happens during a concussion?

A concussion is caused by a jolt to the head, resulting in temporary chemical changes and effects on cognition.

What is multiple sclerosis?

An autoimmune disorder characterized by myelin loss in central nerve fibers, leading to impaired conduction.

What role does the autonomic nervous system play in the body?

The autonomic nervous system regulates involuntary functions such as heartbeat, digestion, and smooth muscle contractions.

What are the two divisions of the autonomic nervous system?

Sympathetic nervous system and Parasympathetic nervous system.

What is the significance of the hypothalamus?

The hypothalamus regulates the autonomic nervous system and controls hormone production, autonomic functions, body temperature, and appetite.

What characterizes the fight-or-flight response triggered by the sympathetic nervous system?

This response prepares the body for emergency situations, increasing heart rate, blood pressure, and blood flow to muscles.

What is the primary neurotransmitter used in the sympathetic division?

Norepinephrine.

What is the primary neurotransmitter used in the parasympathetic division?

Acetylcholine.

What is the function of the myelin sheath in neurons?

The myelin sheath insulates axons and enhances the speed of nerve impulse transmission.

What is an action potential?

An action potential is a rapid electrical signal that travels along the axon of a neuron.

What role do dendrites play in a neuron?

Dendrites receive incoming signals from other neurons and convey this information to the cell body.

What are neurotransmitter receptors?

Neurotransmitter receptors are proteins on the postsynaptic neuron that bind neurotransmitters and trigger responses.

What is the role of afferent neurons?

Afferent neurons carry sensory information from the body to the central nervous system.

What is the role of the cerebellum?

The cerebellum coordinates voluntary movements and maintains balance and posture.

What is a neural pathway?

A neural pathway is a series of connected neurons that communicate with each other to process information.

What is the significance of reflex actions?

Reflex actions are rapid, involuntary responses to stimuli that help protect the body from harm.

What does the parasympathetic nervous system primarily regulate?

The parasympathetic nervous system primarily regulates rest and digest functions in the body.

What is the role of the sympathetic nervous system?

The sympathetic nervous system prepares the body for 'fight or flight' responses, increasing heart rate, blood flow to muscles, and energy availability.