CNS-anatomical division, function, neurons,meninges, Flashcards
-Body’s neural control center
- Brain and spinal cord
- Central nervous system (CNS
-Located outside the nervous system
-Consists of nerves and sensory receptors
- Peripheral nervous system (PNS)
-carry afferent (incoming) messages to the brain or
spinal cord.
- Carries impulses from sensory receptors to the CNS
Sensory division
- Carries impulses from CNS to effectors
-carry efferent (outgoing) messages away from the
brain and spinal cord.
- Motor division
-Motor division has two divisions:
○ Somatic nervous system
○ Autonomic nervous system
-Voluntary control of skeletal muscle
Somatic nervous system
-Involuntary control of cardiac muscle, smooth muscle, and glands
Autonomic nervous system
The autonomic division has two subdivisions:
Parasympathetic
Sympathetic
-sends electrical messages to carry out functions for
vegetative activities such as digestion, defecation, and
urination.
Parasympathetic
-sends electrical messages to prepare the body for
physical activity, often referred to as fight or flight
Sympathetic .
Neurons have basically three parts:
dendrites
cell bodies
axons
-receives information
- A neuron may have anywhere from 1 to 1,000 ________
- The more _______ the neuron has, the more information it can process.
- make multiple connections and form precise pathways.
- Incoming messages travel from the dendrites toward the body
Dendrites
-are involved in protein synthesis
-nucleus and organelles for protein synthesis
-Neurotransmitters are made in the ____ of the neuron
through protein synthesis.
Body
-transmit electrical impulses.
-____ leaves the neuron body at the axon hillock, also
called the trigger zone.
-A synaptic knob at the end of each branch forms a synapse (junction)
Axon.
○ Several dendrites
○ Single axon
* Neurons whose cell bodies are located in the brain and spinal
cord are _____
multipolar neurons
- Two processes:
○ Dendrite
○ Axon - occur in the sensory portions of the eyes,
ears, and nose
Bipolar neurons
- A single process extending from the cell body
-Process divides into two branches extending in opposite
directions
-Branches function as a single axon
-sensory from the skin and organs
Unipolar neurons
There are six types of neuroglial cells that aid in neuron
function:
Ependymal
Microglia
Oligodendrocytes
Astrocytes
schwann cells
satellite cells
form myelin in the CNS.
Oligodendrocytes
cells produce cerebrospinal fluid in the
CNS.
Ependymal
form the blood-brain barrier in the CNS.
-most numerous
-maintain chemical concentration
-repair
Astrocytes
astrocytes that fill space with scar tissue
Sclerosis
-axon emerges frim cell body
-initial part of axon
Axon Hillock
-jumping conduction known as saltatory conduction
Nodes of Ranvier
