NS Bio 29/30 Flashcards
(88 cards)
CNS
brain and spinal cord
PNS
Located outside the CNS, consists of cranial nerves, spinal nerves, and associated ganglia
SNS and ANS
Cranial nerves connect
brain to organs mainly in the upper body (12pairs)
Spinal nerves
connect spinal cord to parts of the body below the head. 31 pairs of spinal nerves.
SNS
Voluntary, carries impulses to skeletal muscles, tendons, and skin
ANS
Involuntary, impulses are transmitted to cardiac muscle, smooth muscle, or glands.
Sympathic, Parasympathetic, and Enteric
Sensory neurons (afferent)
Information from the internal and external environment and transmits them to the CNS.
Motor Neuron (efferent)
relays signals from the brain and spinal cord to muscle or glands cells.
Ganglion
Mass of neuron cell bodies usually found outside the CNS
Neuron
Includes cell body, axon, dendrites. 100 billion +, no mitosis, very poor regen.
Nissl bodies
Rough E.R. in neurons.
Astrocytes
Contain glycogen, star shaped cells, most numerous glial cell. Regulating electrical impulses, provide lactate for nutrition, K+ transport channels, regulate blood flow.
Glial cells
Surround nerons and provide support/protection. Most abundant cells in CNS. E.g. Astrocytes, oligodendrocytes, Schwann cells, microglia, satellite cells, and ependymal cells.
Axon
Extension of neuron that carries nerve impulses away. No neuron has more than a singal axon.
Dendrite/ Soma
Highly branched extensions that bring nerve impulses towards the cell.
Mitochondria in the NS
Most abundant at the axon terminals.
Oligodendrocytes
Make myelin in the CNS
Schwann Cells
Make myelin in the PNS
Blood brain barrier
High density cells that prevent the passage of substances such pathogens, antibiotics, and chemicals.
Multiple Sclerosis
Auto immune. Break down of the BBB of the CNS. T Lymph attach myelin sheath.
Epilepsy
BBB failure that leads to seizures.
Sympathetic NS
Flight or fight
Inc HR, BP, respiration, skeletal muscle blood flow, pupil dilation, stims adernal medulla (epi and norepi),
and glycogenolysis.
Dec intestinal and stomach movements, salivary gland secretion, urine production, and relaxes urinary bladder.
Parasympathetic NS
Rest and digest
Dec HR, BP, blood flow to skeletal muscles, pupil constriction.
Stims intestinal and stomach movements, salivary gland secretions, increase urine production, tenses urginary bladder.
Enteric Nervous System
Entire length of the alimentary tract - esophagus to anus. Controls the secretory and motile functions of our digestive tract.
Makes over 30 nt, 90% of serotonin is made the gastrointestinal tract and a large amount of dopamine too.