BMS 595 Human Phys: Organization of the Nervous System

How many neurons are contained in the CNS?

More than 100 billion

What type of neurons take nerve impulses from the CNS to muscles or glands?

Motor Neurons

What type of neurons take nerve impulses from sensory receptors in muscles, glands, and tissues and send it to the CNS?

Sensory Neurons

What type of neurons are considered association neurons and occur entirely within the CNS? They also convey nerve impulses between various parts of the CNS.

Interneurons

What is the CNS composed of?

Brain and Spinal Cord

What is the PNS composed of?

cranial nerves and spinal nerves

How many pairs of spinal nerves are there in the PNS?

31 Pairs

How many pairs of cranial nerves are there in the PNS?

12 Pairs

What are the three major areas of the brain?

1. Cerebrum

2. Cerebellum

3. Brain stem

What major area of the brain is composed of the telencephalon and diencephalon?

Cerebrum

What are the 4 major lobes of the cerebrum?

frontal, parietal, temporal, occipital

What major area of the brain functions in intellectual processes and sensory information processing?

Cerebrum

What are the two major parts of the diencephalon?

thalamus and hypothalamus

What area of the diencephalon relays stimuli and signals for processing and interpretation?

Thalamus

What area of the diencephalon monitors temp, blood glucose levels, hormone levels and helps maintain homeostasis?

Hypothalamus

What major area of the brain is located behind the brainstem, helps monitor and regulate movement, and integrates postural adjustments and equilibrium?

Cerebellum

What major area of the brain is composed of the midbrain, pons, and medulla oblongata?

Brainstem

What major area of the brain controls respiratory and cardiovascular centers?

Brainstem

What part of the somatic nervous system carries sensations from the periphery (muscles, tissues, etc.) to the spinal cord?

Somatic Afferent (Sensory)

What part of the somatic nervous system communicates from the spinal cord to skeletal muscles?

Somatic Efferent (Motor)

What are the two divisions of the autonomic nervous system?

1. Sympathetic Division

2. Parasympathetic Division

What division of the autonomic nervous system is responsible for increasing activity in most systems and adrenergic fibers release epinephrine?

Sympathetic division

What division of the autonomic nervous system is responsible for slowing activity in most systems and cholinergic fibers release acetylcholine?

Parasympathetic division

where do parasympathetic fibers arise from?

neurons in the brainstem and sacral region

Where do parasympathetic fibers leave the CNS?

Through cranial nerves 3, 7, 9, and 10

The knee jerk response is what type of reflex?

Autonomic Reflex

The crossed extensor reflex is what type of reflex?

Complex Reflex

A single motor neuron and all of the muscle fibers it innervates is called?

A motor unit

What are the two basic types of neurons?

Motor and Sensory

What are the three basic parts of a neuron?

Axons, Dendrites, and Cell Body

What side of the spinal cord do sensory nerves enter?

Dorsal Side of the Spinal Cord

Where do the cell bodies for sensory nerves lie?

Outside the spinal cord in the dorsal root ganglia

What side of the spinal cord do motor nerves exit?

The ventral side

What part of the neuron receives stimuli and carries it to the cell body?

Dendrites

What part of the neuron is the site of cellular activity?

Cell Body

What type of motor nerves have larger fibers, conduct impulses faster, and innervate regular muscle fibers?

Alpha Motor Nerves

What type of motor nerves have smaller fibers, conduct impulses more slowly, and innervate proprioceptors such as muscle spindles?

Gamma Motor Nerves

Muscle spindles, golgi tendon organs, pacinian corpuscles, and ruffini endings are all _________________________.

Proprioceptors