BIOS 1710 SI Week 1 Session 2

Tuesday 7:05-8:05 Morton 326

Thursday 7:05-8:05 Morton 218

  1. What is a nervous system? What are the two cell types?
  1. What are the three types of nerve cells? Describe and draw each of them.
  1. ______received stimuli and send signals to ______, which then interprets the signal and sends another message to ______.
  1. Do all animals have nervous systems? If not, please describe which organisms do and which don’t.
  1. What is the simplest time of nervous system?
  1. What is cephalization? Why did it occur?
  1. Draw a neuron and label all of the parts (cell body/soma, dendrites, axon, synapse, axon hillock).
  1. Describe the functions of the following:
  2. Dendrites
  1. Synapse
  1. Cell body
  1. Axon hillock
  1. Axon
  1. What happens when a stimulus is received by a neuron?
  1. What is the space between two neurons called? How wide is this space?
  1. Which of the following statements is false?
  2. Axons are usually longer than dendrites.
  3. Dendrites generally conduct information towards the soma
  4. Information is received on dendrites, but rarely on axons or the soma
  5. None, all of the above are true.
  1. What are the major functions of glial cells? Where are glial cells most abundant?
  1. What are the three types of glial cells? Their functions?
  1. What is the function of a myelin sheath?
  1. What is “white matter”? “Gray matter”?
  1. What is the estimated resting membrane potential?
  1. How do we get this resting membrane potential?
  1. Where are ion concentrations high and low in a neuron?
  1. Why does the charge not balance out in e neuron?
  1. What happens when a potassium ion leaves the neuron?
  1. The Na/K ATPase imports ______K ions and exports ______Na ions and is responsible for maintaining ______.
  1. Assume E(K)=-85 mV and E(Na)=+68 mV
  2. If the cell were permeable to only K, the resting potential would be -85 mV.
  3. If the cell were permeable to only Na, the resting potential would be +68 mV.
  4. Neither 1 nor 2 is true. The potential would be somewhere between -85 and +68 mV.
  5. Both 1 and 2 are true.
  1. What are the three steps in an action potential? Describe what happens in these steps.
  1. Is the threshold always the same in every neuron?
  1. How long does an action potential last?
  1. T/F : Action potentials can fire half way or partially. They can always be different shapes and durations. The frequency and patterns of action potentials are no meaningful, but their sizes are.
  1. T/F : neurons can fire during their refractory period.
  1. Regarding action potentials, which statement is false:
  2. During depolarization, Na channels are open.
  3. During repolarization, K channels are open.
  4. During early hyperpolarization, K channels are open.
  5. During hyperpolarization and repolarization, Na channels are closed.
  6. None, all are true.
  1. Who were the discoverers of the process of action potentials?
  1. Which channels open slowly? What happens due to these channel’s slow closing?
  1. Why do action potentials propagate?
  1. Action potentials fired from both ends of the neuron will do what? Why?
  1. What if you fire an action potential in the middle of the axon?
  1. What does the speed of an action potential depend on? How do some animals compensate this?
  1. What happens due to myelination? Can you draw a diagram of what happens on a neuron?
  1. In patients with MS, the myelin sheath degenerates. What are the effects of this illness?