Nervous System Flashcards
Human nervous system
- senses m, interprets, and issues commands on a response to conditions in the body’s environment
- made possible by grid of neurons
- messages sent via action potential along neuron to neuron
- chemical synapse is released on point of contact
Functional types of neurons: sensory
- transmits signals to the central nervous system from the receptors associated with pain, temperature, hearing, site, smell, and taste
Functions of neurons: motor
- transmits signals from CNS to rest of body by signaling muscles or glands to respond
Functional types of neurons: inter neurons
- transmit signals between neurons
- between sensory neurons and motor neurons
Neuron
- the cell body, Axon, many dendrites
- dendrites receive impulse from sensory receptors and transmit them towards the cell body.
- axon transmits impulse away from cell body which terminated at the synapse
Central nervous system: spinal cord
- encased with bony structure called vertebrae— protects and supports
- functions mainly to limb movement and internal organ activity
- major nerve tracts ascend and descend from spinal cord to brain
Central nervous system: brain
- hindbrain includes medulla oblongata, cerebellum, and pons
- midbrain sends sensory signals and organizes responses
- forebrain includes cerebrum, thalamus, hypothalamus
Cerebral cortex
-thin layer of gray matter covering the cererbrum
Frontal lobe
- located in front of brain
- short term and working memory and information processing as well as decision making, planning and judgement
Parietal lobe
- slightly toward back of brain and top of head
- sensory input and spatial positioning of body
Occipital lobe
- back of head, above brain stem
- visual input, processing, and output
Temporal lobe
- located left and right sides of brain
- auditory input, processing, and output
Cerebellum
- processing and storing of implicit memories (classical conditioning memories)
Brain stem
- midbrain, pons, and medulla oblongata
- info sent to brain through brain stem and info from brain sent to body through brain stem
- respiratory, digestive, and circulatory
Midbrain
- tectum, tegmentum, and ventral tegmentum
- vision and hearing
- medulla oblongata is beneath, which connects spinal cord to brain and is important role with autonomic nervous system in circulatory and respiratory system
Autonomic nervous system
- maintains homeostasis
- controls functions of internal organs, blood vessels, smooth muscle tissue, and glands by using hypothalamus
- hypothalamus helps maintain stable body environment by regulating HR, BR, body temp, and blood pH
Sympathetic nervous system
- controls body’s reaction to V extreme stress (signals adrenal glands to secrete adrenaline, dilate pupils and slow digestion)
Parasympathetic nervous system
- counteracts effects from Sympathetic system (decreases HR, signals to stop adrenaline, constricts pupils)
Somatic nervous system
- controls 5 senses and voluntary movement of skeletal muscle
- neurons that are connected to sense organs
Efferent nerves
- bring signals from CNS to sensory glands and muscles
Afferent nerves
- brings signals from sensory organs and muscles to CNS
Reflex
- simplest act of nervous system
- automated response without thought
- simplest nerve pathway, bypasses brain and controlled by spinal cord
