Nerve Physiology Flashcards
2 major regulatory systems in the body
Nervous system
Endocrine system
Regulated relatively slow, long-lived responses
Endocrine system
Regulated fast, short-term responses
Nervous system
2 organs in the Central Nervous System
Brain
Spinal cord
2 divisions of Peripheral Nervous System
Somatic Nervous System
Autonomic Nervous System
What Somatic Nervous System controls
Skeletal muscle
2 subdivisions of Autonomic Nervous System
Parasympathetic division
Sympathetic division
What Autonomic Nervous System controls
Smooth muscle
Cardiac muscle
Glands
4 effectors
Skeletal muscle
Smooth muscle
Cardiac muscle
Glands
3 receptors
Special sensory receptors
=provide sensations of smell, taste, vision, balance, hearing
Somatic sensory receptors
=monitor skeletal muscles, joints, skin surface; provide position sense and touch, pressure, pain, or temperature sensations
Visceral sensory receptors
=monitor internal organs, including those of cardiovascular, respiratory, digestive, urinary, or reproductive systems
Sensory receptor (eyes)
Sensory input
Integration (brain and spinal cord)
Motor output
Effector (muscle)
____ signal in one neuron must be transformed into a ____ signal if it is to be passed on to another cell
Electrical
Chemical
What types of cells are found in the nervous system?
Neurons: excitable cells
Neuroglia: supporting cells (glial cells)
Most important cells for producing coordination
Communicate information using a combination of electrical and chemical signal
Neurons
Membranes of most neurons are _____
Electrically excitable
3 main parts of a neuron
Cell body
Dendrites
Axon
8 neurotransmitters
Adrenaline
Noradrenaline
Dopamine
Serotonin
Gaba
Acetylcholine
Glutamate
Endorphins
Fight or flight neurotransmitter
Adrenaline
Produced in stressful or exciting situations.
=increases heart rate and blood flow, leading to a physical boost and heightened awareness
Concentration neurotransmitter
Noradrenaline
Affects attention and responding actions in the brain, and involved in fight or flight response.
=contracts blood vessels, increasing blood flow
Pleasure neurotransmitter
Dopamine
Feeling of pleasure, and also addiction, movement, and motivation.
People repeat behaviors that lead to dopamine release.
Mood neurotransmitter
Serotonin
Contributes to well-being and happiness, helps sleep cycle and digestive system regulation.
Affected by exercise and light exposure.
Calming neurotransmitter
Gaba
Calms firing nerves in the CNS.
High levels improve focus; low levels cause anxiety.
Also contributes to motor control and vision
Learning neurotransmitter
Acetylcholine
Involved in thought, learning, and memory.
Activates muscle action in the body.
Also associated with attention and awakening.
Memory neurotransmitter
Glutamate
Most common brain neurotransmitter.
Involved in learning and memory, regulates development and creation of nerve contacts.
Euphoria neurotransmitter
Endorphins
Released during exercise, excitement and sex, producing well-being and euphoria, reducing pain.
Biologically active session shown.
Types of neurons
Anaxonic neuron
Bipolar neuron
Pseudounipolar neuron
Multipolar neuron
Neurons that have more than 2 processes, but alone cannot be distinguished from the dendrites
Anaxonic neuron
Neurons that have 2 processes separated by the cell body.
Bipolar neuron
Neurons that have a single elongate process with the cell body situated to 1 side.
Pseudounipolar neuron
Neurons that have more than 2 processes; there is a single axon and multiple dendrites
Multipolar neuron
3 types of multipolar cells
Motor neuron (spinal cord)
Pyramidal cell (hippocampus)
Purkinje cell (cerebellum)
Neural circuits I
a) Divergence
b) Convergence
Neural circuits II
c) Serial processing
d) Parallel processing
e) Reverberation
What do neurons do?
- Sensory perception of stimuli
- Integration
- Motor output (muscles, glands)
Conduct signals from receptors to the CNS
Sensory (afferent) neurons
Neurons that conduct signals from the CNS to Effector such as muscles and glands
Motor (efferent) neurons
Interneurons (_______) are confined to the CNS
Association neurons
Why are neurons among the most thoroughly studied of all cell types?
- Neurons transmit information electrically, which allow scientists to monitor the activity of individual neurons by using various instruments originally developed for the physical sciences.
- Recordings of electrical activity in neurons have revealed that the properties of individual neurons from nearly all animals are similar.
- Neurons process information in a highly sophisticated manner, but in doing so they rely on the surprisingly small number of physical and chemical processes, making it possible to formulate general principles about their function.
All of the neurons in an organism’s body, along with supporting cells
Glial cells
9-10 times more common than neurons
How many in CNS
How many in PNS
Glial cells
4
2
Found in the parenchyma of brain and spinal cord
Neuroglial cells
Lining the internal cavities or ventricles
Ependymal cells
Surrounding neurons of the sensory and autonomic ganglia
Capsular or satellite cells
Forming sheaths for axons of peripheral nerves
Schwann cells
Ensheating the motor and sensory nerve terminals, and supporting the sensory epithelia
Several types of supporting cells
Glial cells include…
Neuroglial cells
Ependymal cells
Capsular or satellite cells
Schwann cells
Several types of supporting cells