Neurons And Action Potentials Flashcards
Roughly how many neurons are found in the cerebrum and cerebellum, respectively?
12 to 15 billion neurons in the cerebrum, and ~70 billion neurons in the cerebellum.
Two scientists are widely recognized as the founders of neuroscience. Who are they?
Santiago Ramon y Cajal and Charles Sherrington.
Whats the difference between a motor neuron and sensory neuron?
A motor neuron has its soma in the spinal cord and is efferent, a sensory neuron has a highly specialized sensory ending and its soma is outside of the spinal cord and is afferent.
How does Saltatory Conduction work?
Saltatory conduction is “the jumping of action potentials” from one node of ranvier to another. In reality the myelin sheaths allow for the rapid propagation of ions throughout the axon, allowing for each node to quickly reach its action potential.
Whats the function/s of astrocytes?
Star-shaped astrocytes envelope presynaptic terminals taking up and releasing their ions/ neurotransmitters to synchronize their activity. They also remove waste and direct blood flow.
Whats the function/s of microglia?
Removes waste and microorganisms functioning like the immune system (macrophages).
Whats the function/s of Oligodendrocytes?
Insulates multiple central nervous system axons in myelin sheaths to propagate a saltatory conduction.
What/s the function of Schwann cells?
Schwann cells myelinate one axon in the peripheral nervous system to propagate a saltatory conduction.
What can pass and what cannot pass the blood brain barrier?
Small, uncharged, and lipid-soluble molecules readily cross the barrier. Glucose and amino acids are actively transported across.
Large, lipid-insoluble, charged particles can NOT cross.
What vitamin is vital for the body and brain to effectively process glucose?
Vitamin B1, or Thiamine. An undernourishment can be caused by severe alcoholism and lead to neuronal cell death, a disease known as Korsakoff’s syndrome.
