Nervous system Flashcards
Name the parts of the CNS
Brain and spinal cord
Name the three principle parts of a neuron
- Dendrites
- Cell body
- One axon
Describe the functions of the glial cells in nervous tissue
Glial cells:
- Are supporting cells of the nervous tissue
- Are non-excitable
- Bind/support neurons
- Insulate/myelinate the neurons
What is the function of the autonomic nervous system?
It controls the activity of the internal organs and vessels
How are the 31 pairs of spinal nerves subdivided?
8 Cervical 12 Thoracic 5 Lumbar 5 Sacral 1-2 Coccygeal
Ventral roots of spinal nerves carry ________ fibres
motor
Dorsal roots of spinal nerves carry ________ fibres
sensory
An area of skin supplied by a single spinal nerve root is known as a
dermatome
In which disease may a dermatome be outlined?
Shingles (Herpes Zoster)
What is the main difference between cranial nerves and spinal nerves?
Cranial nerves emerge directly from the brain or brainstem, whereas spinal nerves emerge from segments of the spinal cord
Nervous tissue is grouped into two main categories
Neurons and neuroglia
Cells of the NS that broadly communicate with each other through neurotransmission
Neurons
Direction of the nerve impulse conduction is from the cell ____ to the ____ terminal.
body, axon
This structure (structures) detect incoming information and conducts impulse towards the cell body
Dendrites
Which part of the neuron contains the organelles?
Soma (cell body)
This is the part of a neuron that conducts impulses away from the soma towards the axon terminal
axon
This part of the neuron contains neurotransmitters to be released in the synaptic gap
axon terminal
Which cells myelinate neurons in the CNS?
Oligodendrocytes
Which cells myelinate neurons in the PNS?
Schwann cells
A neuron that have a single axon ONLY is called a
unipolar neuron
Primary sensory neurons are typically classified as what type (?polar)
Unipolar
Neurons that have one axon and one dendrite are called
bipolar neurons
What type of tissue has bipolar neurons?
Specialised sensory neurons, such as those found in the retina
This type of neuron has one axon and multiple dendrites
Multipolar neuron
The majority of the neurons in the brain are of what type?
Multipolar
Name the three distinct types of multipolar neurons
- Motor (spinal cord)
- Pyramidal (hippocampus)
- Purkinje (cerebellum)
Neurons that convey information from the tissues and organs into the CNS are called
Afferent or sensory neurons
Neurons that transmit signals from the CNS to effector muscles are called
Efferent or motor neurons
Efferent (motor) neurons can be divided into what two categories of the nervous system?
Autonomic or somatic (innervation of skeletal muscle)
The autonomic NS can be divided into what two categories?
Sympathetic and parasympathetic
What are the most numerous cells of the nervous system?
Glial cells (or neuroglial)
Glial cells outnumber neurons by how much?
10:1
Oligodendricytes are found only within the
CNS
Which cells are responsible for the production and maintenence of the myelin sheath within the CNS?
Oligodendricytes
What is myelin made of?
Myelin basic protein and phospholipid
These are a network of “delicately ramified” cells that are activated by pathogens. Phagocytic, immune cells.
Microglia
These cells provide structural support, supply nutrients to the neurons (glucose) and maintain the ionic environment by removing K+ from the CNS. Assist with NT uptake.
Astrocyte
Which of the neuroglial cells makes up the blood brain barrier?
Astrocytes (think Sweet Sweet Sweet Star Star Star, Blood Brain Barrier)
What are the two types of synapses that can occur in neurotransmission?
Electrical or chemical
This type of synapse allows the direct passage of ions and signalling molecules from cell to cell.
Electrical
Neurons in the hippocampus, olfactory bulb, and retina use what type of synaptic transmission?
Electrical
The peripheral nervous system is comprised of what type of nerves (two groups?)
Cranial nerves and spinal nerves
What 3 structures make up the forebrain? (actually one of the structures is comprised of two parts)
- Cerebral hemispheres
- Thalamus
- Hypothalamus
What is the term for the white matter tract that connects the right and left hemispheres of the brain?
The Corpus Callosum
The hindbrain is mainly comprised of what structure?
The cerebellum
The brain stem is in what region of the brain?
Midbrain
The primary motor cortex is located in what region/lobes of the brain?
Frontal lobes
This is the part of the brain responsible for executive functions, ability to think and consider, and also houses the primary motor cortex
Frontal lobes
This region of the brain contains the primary auditory complex
Temporal
This region of the brain contains the primary somatosensory cortex, responsible for recognition of pain, touch, and proprioception
Parietal
Which region of the brain contains the primary visual cortex?
Occipital
The hypothalamus is in which region of the brain?
Forebrain
This is the region of the brain that is most important n maintaining homeostasis. It contributes to control of autonomic NS, endocrine system, thermoregulation, satiety, and circadian rhythms.
Hypothalamus
Damage to the brain stem will most likely be…
fatal
This structure in the brain is responsible for motor movements, modification of muscular activity, regulating sensory systems, and balance/posture
cerebellum
The peripheral nervous system is comprised of what three subdivisions?
- Nerves
- Somatic system
- Autonomic system
Which is the involuntary aspect of teh PNS?
Autonomic NS
Sympathetic nerves synapse close to the ______ _______
vertebral column
Nerves conducting a sympathetic response originate from which part of the CNS?
Thoracic & lumbar
Sympathetic nerve fibres have a ______ pre-ganglionic region
short
Parasympathetic nerve fibres originate from what parts of the CNS?
Cranium (brainstem) and sacrum
Parasympathetic nerve fibres have a ____ pre-ganlionic nerve fibres
long
Parasympathetic nerve fibres synapse near
the target organ
All preganglionic, sympathetic axons enter the
sympathetic trunk
Nerve fibres that have long preganglionic region and a short post-ganglionic region are associated with which NT?
Acetylcholine
Motor neuron axons exit the ________ root of the spinal cord
ventral
The spinal cord extends from ____ to_____
C1 to L1-L2
The inner core of the spinal cord is made up of _____ matter, which consists of neuronal ____ ________
gray, cell bodies
The outer region of the spinal cord is made up of ______ matter, with are _________ axona
white, myelinated
Spinal nerves exit the spinal canal via the _______ _______ of the corresponding vertebrae
intervertebral foramina
What are the nerve roots called when they first exit the spinal cord (prior to merging where they become the spinal nerve)?
ventral and dorsal nerve roots
Spinal nerves are made up of what types of fibres?
Motor, somatosensory, autonomic
Visceral pain can be referred to the skin (dermatomes), and this is referred to as _________ pain.
cutaneous
This is an area of skin responsible for sensory input to a single dorsal root
Dermatome
Pain corresponding with a particular dermatome can indicate possible injury to…
spinal cord, nerve root, or a spinal nerve
An individual set of muscles innervated by a single spinal nerve is called a
myotome
The functional role of this branch of the nervous system is to quickly mobilise energy and direct blood flow towards the heart
Sympathetic
The loss of the myelin sheath, leading to axonal conduction block and neurodegeneration
Demyelination
Is a demyelinated cell the same thing as an unmyelinated cell?
No
Multiple sclerosis is a demyelinating disorder of the ______
CNS
Gillan Barre syndrome, chronic inflammatory demyelinating ployneuropathy, and Charcot-Marie-Tooth are diseases demyelinating disorders of the_____
PNS