Nervous System Flashcards
What is the Central Nervous System composed of?
Brain and Spinal Cord
What is the Peripheral Nervous System composed of?
Nervous structures outside the CNS (nerves and ganglia)
What are the subdivisions of the PNS?
PNS
–> Somatic nervous system (voluntary)
–> Autonomic nervous system (involuntary)
- Sympathetic (fight or flight)
- Parasympathetic (rest and digest)
What is the role of the autonomic nervous system?
Autonomic sensory neurons and autonomic motor neurons convey information from the CNS to smooth muscle, cardiac muscle and glands. (regulates the activity of cardiac muscles, smooth muscle and glands)
What is the role of the somatic nervous system?
Somatic sensory neurons and somatic motor neurons (voluntary) convey information to and from the CNS to and from skeletal muscles.
What is the role of neurons?
Neurons are able to generate electrical impulses in response to stimuli.
What are sensory neurons?
Sensory nears pick up information in the periphery and relay it back to the spinal cord and the brain.
What are motor neurons?
Motor neurons relay information away from the brain and spinal cord out to the periphery (to glands and muscle cells).
Draw a motor neuron.
Draw a sensory neuron.
What are glial cells?
Glial cells help to protect and maintain healthy function of neurons.
E.g. insulation of neurons (myelin) so that electrical signals can travel more quickly.
CNS - e.g. Astrocytes, oligodendrocytes, microglia
PNS - e.g. Schwann cells
What is / what is the role of myelination?
Myelin is formed by glial cells wrapping themselves around the axon of a nerve cell. PNS - Schwann cells, CNS - oligodendrocyte.
Myelin insulates the cell membrane of the nerve cell against flow of electrical current - preventing formation of action potentials. Myelination increases the speed of electrical communication down the length of the axon.
What are the types of neurons / draw a picture?
- Multipolar neuron (located in the brain and spinal cord)
- Bipolar neuron (located in the retina, inner ear and olfactory area)
- Unipolar neuron (sensory receptors for touch, pressure, pain, temperature)
Draw and explain neurotransmitters and the synapse?
What cavities are the brain and spinal cord (CNS) enclosed within?
The cranial cavity and the vertebral cavity.