Neuro study guide Flashcards
Definition of Central Nervous System (CNS)
Brain and spinal cord. Covered by the meninges.
Definition of Autonomic Nervous System (ANS)
SYMPATHETIC & PARASYMPATHETIC NERVOUS SYSTEM: Neuron soma clustered in ganglia near CNS; axons project to visceral organs, blood vessel smooth muscle, hair follicles, and sweat glands (INVOLUNTARY motor system)
Definition of Peripheral Nervous System (PNS)
Lies outside the dura mater.
Include sensory receptors, spinal and cranial nerves that carry impulses away from or toward the CNS and peripheral portions of autonomic nervous system.
Definition of Visceral neurons
To cardiac muscle
to smooth muscle
to exocrine glands
Definition of Somatic neurons
To skeletal muscle
Meaning of Afferent
Sensory (afferent) nerves carry messages from the periphery to CNS
Meaning of Efferent
Peripheral motor (efferent) nerves carry messages from the CNS to peripheral tissues
Motor nerves
Motor neurons are in CNS, but their axons bundle into nerves and travel peripherally to skeletal muscles (VOLUNTARY & REFLEXIVE motor system)
SENSORY NERVOUS SYSTEM
Neuron soma clustered in ganglia near CNS; axons bundled into nerve fibers projecting to periphery and into CNS
Parts of the CNS
Prosencephalon—forebrain
Mesencephalon—midbrain
Rhombencephalon—hindbrain
spinal cord
Telencephalon
Made of the cerebral cortex, basal ganglia and hippocampus.
For a number of functions:thinking, learning, memory and consciousness.
Cerebral Cortex
Mediates sensory integration and conscious sensory perception. Formulates and executes voluntary movement.
Basal Nuclei
Collection of nuclei that modulate motor functions of cerebral cortex
Hippocampus
Spatial learning and memory
Diencephalon
Relay between brainstem and cortex
Thalamus
Sensory relay ( not smell)
Relay station and modulator of information being passed to the cerebral cortex from sensory systems and other brain regions
Hypothalamus
Autonomic control center for visceral functions (e.g., blood pressure, rate and force of heartbeat, digestive tract motility)
Brain stem
Consists of Midbrain, pons, and medulla
Caudal brainstem serves as a passage for axons traveling from higher CNS centers to the spinal cord (descending pathways) and vice versa (ascending pathways).
Pon
Contains somatic motor neurons that control
nucleus for CN V (mastication)
nucleus for CN VI (eye movement)
nucleus for CN VII (facial muscle)
Receives somatic sensory information from the face, scalp, mouth, and nose (portion of the nucleus for CN V).
Medulla
Receives information from sensory receptors through cranial nerves and sends motor commands to skeletal and smooth muscle
The medulla is involved in controlling blood pressure, heart rate, respiration, and digestion
- nuclei of CN IX and X
The medulla contains somatic motor neurons that innervate the
nucleus of CN XI (muscles of the neck)
nucleus of CN XII (tongue)
Meninges
From outer to inner
Dura Mater
Arachnoid Space
Pia Mater
Meninges
Dura Mater
Arachnoid Space
Pia Mater
Organization of PNS
Sensory (afferent division)
-Somatic
- Visceral
Motor (efferent division)
-Somatic Nervous system or visceral
- Autonomic Nervous system
- sympathetic or parasympathetic
Neuron
Dendrite
Axon
Soma
Astrocyte
Main glycogen storage of CNS, provides lactate
Oligodendrocyte
Myelination in the CNS
Schwann cells
Myelination in the PNS
Microglia
Phagocytize in CNS
Axoplasmic transport
Electric Synapse
Chemical Synapse
Main difference between electric and chemical synapse
Neuromuscular Junction definition
Structure of neuromuscular junction
Neurotransmitter cycle
Neurotransmitter cycle: Synthesis
Neurotransmitter cycle: Transport
Neurotransmitter cycle:Storage
Neurotransmitter cycle: Release
Neurotransmitter cycle: Inactivation
Names of excitatory neurotransmitters
Names of inhibitory neurotransmitters
What is a reflex
Neural components of the reflex arc
Understand what sensory, motor, interneuron etc means.
What does the Muscle Spindle sense and innervations to and from
What does the Golgi Tendon sense and innervations to and from
Skeletal muscle
SKELETAL MUSCLE IS THE EXTRAFUSAL FIBERS. THE INTRAFUSAL FIBERS ARE THE RECEPTORS AND HAVE NO ROLE IN THE FUNCTION OF THE MUSCLE (CONTRACTION)
Extrafusal Fibers
Intrafusal Fibers
Myotatic reflex: Knee jerk. why is it down on the knee and not other muscles
Structure of Muscle
Properties of Muscle
Organization of sarcomere
Structure of thick and thin filaments
T Tubules
Triad
SR (
Slow twitch fibers
Fast twitch fibers
Muscle Synapse and its structures
Action potential in neurons : Muscle contraction
Steps of Action potential
Motor Unit
Motor neuron pool
Summations
Temporal Summation
Spatial Summation
Sequence of events at NMJ during an action potential
Myasthenia gravis
The 3 phases of a twitch
Cross bridge cycle/sliding filament theory – 5 steps
Rigor Mortis
Know the difference of a twitch, Fused and unfused tetany
Fused tetany
Unfused tetany
Twitch
Energy source for muscle ATP
Isometric contraction
Isotonic contraction
Termination of contraction in skeletal muscle
Main difference of smooth from skeletal muscle
Difference of smooth muscle from cardiac and skeletal
- Rate of rise of the action potential in smooth muscle is lower because Ca2+ channels open more slowly than do Na+ channels in skeletal and cardiac muscle.
- Repolarization of the smooth muscle cell is also relatively slow. Two explanations may be offered for this slower repolarization. First, voltage-gated Ca2+ channels, which are responsible for the depolarization phase of the action potential, inactivate slowly. Second, the repolarization phase of the action potential reflects the delayed activation of voltage-gated K+ channels and, in some cases, Ca2+-activated K+ channels.
- They do not contain t tubules, and their sarcoplasmic reticulum is poorly developed
- These cells rely primarily on the transmembrane diffusion of Ca2+ ions from the extracellular fluid to induce the actin-myosin interactions responsible for contraction
- In many smooth muscle cells the sarcoplasmic reticulum is poorly developed, and extracellular Ca2+ influx plays the principal role in initiating the contractile process. Even though smooth muscle cells have no T tubules, this Ca2+ influx is achieved, on membrane depolarization, through activation of voltage-gated Ca2+ channels located in shallow depressions of the membrane (caveolae)
- In skeletal and cardiac muscle, cross-bridge cycling relies primarily on the Ca2+-induced removal of the tropomyosin block of the actin-binding site. In smooth muscle, cycling relies on a Ca2+-induced increase in the ATPase activity of the myosin head, another slow process.
What happens if an excitatory/inhibitory interneuron synapses with a LMN
What does OP poisoning do
What happens in myasthenia
What happens if there is loss of myelination?
Function of Cerebellum
equilibrium, coordination, appropriate adjustment
Layers of cells : Cerebellum
Input and output fibers: Cerebellum
Cerebellum tracts
Diseases related to cerebellum
Local Spinal circuit
Types of movement
voluntary and involuntary, muscles involved, UMN and LMN)
Hierarchical organization of control of movement
Motor system hierarchy
Spinal reflex circuit, flexor reflex
Brainstem Motor pathways
Characteristics of extrapyramidal system (reticulo, tecto, rubro and vestibuo spinal tract)
Corticospinal tract (origin, decussation, end, lateral and ventral tract, lesions)
Premotor cortex
Supplementary motor cortex
Basal Ganglia
Sensory perceptions
