Exam 4 Flashcards
Nervous system and Endocrine system
Nervous is fast endocrine is slow which is minutes to hours
Sense organs
Picks up and send signal to brain afferent
Brain and spinal cord
Processes information. Efferent
Nerves
Cluster of axons
CNS
Central Nervous System. Anything including brain and spinal cord.
PNS
Peripheral nervous system. All of the nerves and ganglia outside the CNS.
Functions of CNS
Processing and coordinate. Originate any kind of signal then send it back out. Interpret sensory information down to skeletal muscle. Higher functions, intelligence memory learning and emotion. Controls activities of peripheral organs.
Functions of PNS
Composed of nerves and ganglia. Deliver sensory information to CNS. Carry motor commands to peripheral tissues and systems.
Nerves
Bundle of nerve fibers(axons) wrapped in fibrous connective tissue.
Ganglion
A knot like swelling in a nerve where neuron cell bodies are concentrated.
Functional divisions of PNS
Afferent division and Efferent divisions.
Afferent Division
Carries sensory information(action potentials). From PNS sensory receptors to CNS.
Interneurons
Carry information from afferent or sensory neurons to efferent or motor neurons through CNS. Confined to CNS.
Efferent Division
Carries motor commands (action potential) away from CNS. From CNS to PNS muscles and glands.
Nerves
Also called peripheral nerves. 43 pairs of nerves originating from CNS. Carry sensory information and motor commands in PNS. 12 cranial nerves connected to brain. 31 spinal nerves attached to spinal cord.
Receptors
Eyes ears. Detects changes and responds to stimuli.
Effectors
Responds to efferent signals. Cells and organs. Skeletal muscle. Action part.
Efferent Division
Somatic nervous system and autonomic nervous system.
SNS
Somatic Nervous System. Controls skeletal muscle contractions. Involuntary muscle contractions (reflexes).
ANS
Autonomic nervous system. Controls subconscious actions. Including Sympathetic Division and parasympathetic Division.
Sympathetic Division
Stimulating effect. Fight or flight.
Parasympathetic Division
Relaxing effect.
Neuralgia
50% of the volume of the nervous system. Outnumber neurons 10 to 1. 6 types in CNS and PNS. Protect neurons and help them function. Glial cells. Very proliferative. Cause of cancer.
Neuroglia in CNS
Ependymal, astrocytes, oligodendrocytes, microglia.
Ependymal cells
Maintenance and secrete cerebrospinal fluid(CSF) and monitor CSF. Contain stem cells.
Astrocytes
Most abundant and do a little of everything. Regenerative. Maintain blood brain barrier.
Oligodendrocytes
Schwann cells of CNS. Resemble and octopus. Myelinate the axons.
Myelination
Increases speed of action potentials. Myelin insulates myelinated axons. Makes nerves appear white.
Microglia
Immune cells within CNS. Clean up cellular debris waste products and pathogens. Become concentrated in damaged areas.
Nodes and internodes
Myelinated segments of axon. Nodes are gaps within internodes called nodes of ranvier where axons may branch.
White matter
Myelinated. Transit areas. Processing center. Where things get perceived. Myelinated highways. Sent down to spinal cord. Three types of tracts; association, commiseral, and projection.
Gray matter
Unmyelinated
Ganglia
Cluster of cell bodies. Found in specific areas. Bumps or nodules throughout a nerve. Writing, typing, driving a car. Voluntary but routine.
Glioma
Type of brain cancer. Blood brain barrier decreases effectiveness of chemotherapy.
Rostral
Towards the forehead.
Caudal
Towards the spine.
4 major portions of the brain
Cerebrum(cerebral hemispheres). 83% of brain volume. Diencephalon. Cerebellum. Brain stem
Gyri
Thick folds of cerebrum separated by sulci.
Sulci
Shallow grooves that separate the gyri.
Longitudinal fissure
Deep groove that separates the cerebral hemispheres.
Corpus callosum
Thick nerve bundle at bottom of longitudinal fissure that connects the hemispheres.
Diencephalon
Right under corpus callosum. Thalamus, hypothalamus, and epithalamus. Forebrain.
Cerebellum
Marked by gyri, sulci, and fissures. About 10% of brain volume but contains over 50% of brain neurons.
Brainstem
Major components: midbrain, pons, medulla oblongata.
Meninges
Skull, dura mater, arachnoid mater, pia mater, brain. S,D,A,P,B
Spiders don’t act purposely bad.
Meningitis
Any kind of inflammation in the meninges. Pressure on brain.
Ventricles
Fluid filled components in brain. 2 lateral. Third goes through. Four at bottom.
Cerebrospinal Fluid
Contained in ventricles. Reduces brain weight by 97%. Used for protection from trauma. Buoyancy to keep brain from being impaired by own weight. Chemical stability by nourishing brain by rinsing metabolic waste from nervous tissue and homeostatically regulates its chemical environment.
Blood supply in brain
2% of adult body weight but receives 15% of blood. High demand of ATP.
Blood brain barrier
Tight junctions to make sure nothing that is not supposed to pass goes through. Permeable to things that are needed.
Forebrain
Cerebrum and diencephalon. Contains thalamus hypothalamus and epithalamus. And third ventricle.
Sensory areas
Areas that pick up information that sensory sensors pick up. Temp and touch.
Association areas
Interpretation areas. Where we perceive that is it hot.
Somatosensory Cortex
Sensory hominculus: body parts in proportion to cortex dedicated to their sensation. Amount of cortico space used to interpret senses. Hands face and mouth. Postcentral gyrus.
Motor Control
Precentral gyrus. Similar to homonculus. Dedicated to hands face. Body parts on proportion to amount of primary motor cortex dedicated to their control.
Basal Nuclei/Ganglia
Voluntary but repetitive movements. Writing, typing, driving a car. Learned behaviors one carries out with little thought. Associated with Parkinson’s disease. Lesions cause dyskinesia.
Cerebellum
Highly repetitive motor coordination. Standing and not falling over. Skeletal muscle control.
Association tracts
Top of brain and middle. Linking within cortex.
Projection tracts
Go down into brain.
Commiseral tracts
Left and right between hemispheres.
Cerebral Lateralization.
“Left brained and right brained”. Functional characteristics. Left is math and science. Right is artistic.
Thalamus
The filter and gateway to cortex. Tells cortex what you want to be aware of.
Hypothalamus
Homeostatic regulation. Regulates petuitary gland which is a major endocrine gland.
Epithalamus
Regulates the pineal gland.
Midbrain
Substantria nigra. A regulatory motor pattern.
Medulla oblongata
Hindbrain. Very primitive things that keep us alive. Heart rate. Vasomotor or adjusts blood vessel diameter. More basic than hypothalamus.
Pons
Hindbrain. Anterior bulge in brainstem. Sleep respiration and posture. Highway system. Pathways in and out of cerebellum.
Cerebellum
Posture and involuntary motor control. Hindbrain. Maintains muscle tone. Spatial perception. Hearing. Planning and scheduling tasks.
Higher brain functions
Sleep, memory, cognition, emotion, sensation, motor control, and language. Limbic system and reticular formation.
Limbic System
Center of emotion, learning, and memory. Ring of structures on medial cerebral hemispheres and diencephalon. Have centers for gratification and aversion.
Gratification
Sensations of pleasure or reward.
Aversion
Sensations of fear and sorrow.
Reticular Formation
Loosely organized web of gray matter that runs vertically through all levels of the brainstem. Had connections with many areas of cerebrum.
Functions of reticular formation
Pain modulation. Sleep and consciousness. Cardiovascular control. Somatic motor control.
Language
Wernicke and broca areas.
Aphasia
Any language deficit from lesions in same hemispheres.
Spinal cord functions
Conduction: pass information up and down spinal cord. Locomotion: walking. Reflexes: involuntary protective movements such as withdrawal of hand from pain.
Enlargement of spinal cord
Caused by amount of gray matter
Spinal cord segments
31 pairs of spinal nerves arise from cervical, thoracic, lumbar, and sacral regions of cord.
Roots
2 branches of spinal nerves. Central and dorsal root.
Ventral Root
Axons of motor neurons.
Dorsal root
Axons of sensory neurons.
Spinal meninges
Dura mater, arachnoid, pia mater
Functions of spinal meninges
Isolate spinal cord from surroundings, protect spinal cord, carry blood supply, continuous with cranial meninges. Meningitis: bacterial infection of meninges.
Ascending tracts
Carry messages up to brain.
Descending tracts
Carry messages down spinal cord.
3 connective tissues of spine
Epineurium, perineurium, endoneurium.
Peripheral Neuropathy
Regional loss of sensory or motor function due to trams or compression.
Norepinephrine
Adrenergenic synapse
Dopamine
CNS. May be excitatory and inhibitory. Involved in Parkinson’s. cocaine use excitatory.
Serotonin
CNS neurotransmitter. Low levels can be related to depression.
GABA
Inhibitory
EPSP
Excitatory postsynaptic potential. Graded depolarization of postsynaptic membrane.
IPSP
Inhibitory postsynaptic potential. Graded hyperpoparizarion of postsynaptic membrane.
Temporal Summation
Multiple times. Rapid repeated stimuli at 1 synapse.
Spatial Summation
Multiple stimuli arrive at multiple synapses.
Autonomic nervous system
Homeostatic functions. Regulation of everything. And some metabolic. Involuntary.
Visceral Reflexes
Internal organs. Unconscious automatic.
Receptors
Detect internal stimuli.
Afferent
From sensory receptor to brain.
Interneuron
Process information in CNS
Short reflexes
1 small part of target. Less synapses.
Sympathetic
Fight or flight. Exercise. Arousal. Trauma. Anger. Short preganglionic fibers. Long postganglionic.
Parasympathetic
Digestion and elimination of waste.
Somatic motor pathway
One long myelinated motor neuron. Attached to skeletal muscle.
Autonomic motor pathway
Signal must travel across two neurons.
Sympathetic divisions
Need heightened energy.
Parasympathetic
Relaxation.
Enteric nervous system
Digestive tract. Runs on own circuitry of nerves. No components of CNS. CNS can override and influence.
Dual innervation
Receive nerve fibers from both sympathetic and parasympathetic
CNS
Can regulate autonomic functions.
