Lec 2: Nervous System Flashcards
Specialized proteins or structures in the body that sense and respond to various stimuli from the internal or external environment
Receptors
Part of the nervous system that contains all the nerves and ganglia outside the brain and spinal cord
Peripheral Nervous System
A part of the peripheral nervous system that controls self-regulated actions of internal organs and glands
Autonomic Nervous System
A part of the peripheral nervous system that controls voluntary movements of skeletal muscles
Somatic Nervous System
A part of the peripheral nervous system that promotes a state of relaxation and conserves energy by slowing down bodily processes
Parasympathetic Nervous System
Pressure necessary to prevent solvent migration
Osmotic Pressure
Highly specific part of the nervous system where each is responsible for a single function
Neurons
They play a crucial role in the functioning of organisms by allowing them to perceive and adapt to changes in their surroundings
Receptors
Responsible for detecting sensory stimuli inside or outside the body
Sensory Receptors
Receptors that play a crucial role in coordination and balance (IMUs of the body)
Proprioceptors
Receptors for dopamine, serotonin and acetyl choline
Neurotransmitter Receptors
Receptors that respond to painful stimuli alerting the body
Pain Receptors or Nociceptors
Receptors that play a crucial role in regulating various physiological processes, including metabolism, growth and reproduction
Hormone Receptors
Crucial component of the body’s feedback system for regulating fluid balance
Osmoreceptors
Receptors that contribute to our perception of internal sensations and help regulate organ function
Visceral receptors
Receptors that detect changes in blood pressure and help regulate it to maintain homeostasis
Baroreceptors
Receptors that lie within body tissues to monitor internal organ functions and provide crucial homeostasis feedback regulation
Visceral Receptors
Location of skin sensory receptors
Dermis
A process in which the receptor converts the stimulus into action potentials
Sensory transduction
Sudden, fast, transitory, and propagating change of the resting membrane potential
Action Potential
At this point a small subset of potassium channels are open, permitting K+ ions to enter and exit the cell based on electrochemical forces. For each K+ ion that leaves the cell, another returns, maintaining the membrane potential at a constant value.
Resting potential
A phase at which Na+ channels open, permitting Na+ ions to enter the neuron.
Depolarization phase
A phase at which many of the voltage-gated sodium channels begin to close. Second, many more potassium channels open, allowing positive charges to leave the cell
Repolarization phase
A phase at which more potassium channels are open at this point than during the membrane’s resting state, allowing more positively charged K+ ions to leave the cell.
Hyperpolarization phase
The period during which the neuron is incapable of generating another action potential, regardless of the strength of the stimulus.
Absolute refractory period
The period during which the neuron can generate another action potential, but only if the stimulus is stronger than usual.
Relative refractory period
a period which allows for control over the frequency of action potentials and prevents excessive firing.
Relative refractory period
It acts as a decision-making center for the neuron, where incoming signals are summed up and evaluated. Determines whether an action potential should be generated or not.
Axon Hillock
Neurons that travel from spinal cord to muscle
Lower motor neurons
Neurons that travel between the brain and spinal cord
Upper motor neurons
A process in which neurons interact together and where neurotransmitter release happens which lead to firing of action potential in the other neuron
Synaptic transmission
A part of the nervous system where filtration and modulation of sensory information happen before reaching higher regions of the brain
Spinal cord and brain stem
The only cells that are capable of generating an action potential
Neurons and muscle cells
A part of the receptor that is deformed by pressure and as a result presses on the tip of the sensory neuron
Lamellae
Type of neurons that transmit info from receptors to CNS
Afferent (sensory) neurons
Type of neurons that carry actuation signals from CNS to effectors
Efferent (motor) neurons
A part of the neuron that prevents excessive excitation, and increases the speed of action potential propagation.
Myelin sheath
A part of the neuron that prevents loss of signals
Myelin sheath (includes fat which acts as insulation)
A small gap or interruption in the myelin sheath that surrounds axons of certain neurons
Node of Ranvier
A mode of action potential travel in myelinated nerve fibers where action potential jumps from one node of Ranvier to the next
Saltatory conduction
A mode of action potential travel where the action potential travels along the entire length of an axon
Continuous conduction
