5 Written questions
5 Matching questions
- Define excitability. What kinds of cells possess excitability?
- What is axonal transport? What is the primary function of slow axonal transport vs fast axonal transport?
- Describe the ionic basis for an action potential (depolarization). What is the ionic basis for repolarization? What is hyperpolarization? What ions are involved?
- What parts of neurons are found in gray matter? White matter? Why is it white?
- What are the two major divisions of the nervous system? Name the three subdivisions of the PNS, and tell how they differ in functions. What are the two subdivisions of the Motor pathway system?
- a Central Nervous System (CNS) and Peripheral Nervous System (PNS)
Autonomic (involuntary). Within this, there are Sympathetic (Fight or Flight) and Parasympathetic (Rest and digest).
- b Depolarization - Potential difference becomes smaller or less polar. If extracellular concentration of K+ increases, there is less gradient between inside and outside.
Hyperpolarization - Potential difference becomes greater or more polar. If extracellular concentration of K+ decreases, steeper gradient between inside and outside
- c Axonal transport is a cellular process responsible for movement of mitochondria, lipids, synaptic vesicles, proteins, and other cell parts (i.e. organelles) to and from a neuron's cell body, through the cytoplasm of its axon
- d Able to receive impulse from action potentials
- e Cell bodies found in gray matter
Because the tissue is composed of fatty tissue.
5 Multiple choice questions
- spatial variation of both electrical potential and chemical concentration across a membrane.
- Not really.
- To travel across the synapse and get the action potential to the next neuron
Ach is acetylcholine
Cholinergic synapses -
- Means that action potential doesn't have to travel down the entire axon, just jumps from node to node.
- Only allows certain things through.
5 True/False questions
Axons are classified into 3 groups according to the relationship between diameter, myelination and propagation speed: define Type A, B and C fibers. → Type A - large-diameter, myelinated. Conduct at 15-120 m/s. Motor neurons supplying skeletal and most sensory neurons
Type B - medium-diameter, lightly myelinated. Conduct at 3-15 m/s. Part of ANS
Type C - small-diameter, unmyelinated. Conduct at 2 m/s or less. Part of ANS
What is a graded potential? Can it travel a long distance? Why or why not? → A change in the membrane potential that is localized to one area of the plasma membrane. Also known as local potentials.
Cannot travel long distances because they spread in a decremental fashion. They rapidly decrease in magnitude as they spread over the surface of the plasma membrane (teacher's voice in a large lecture hall)
How are nerve impulses transmitted across synapses? Compare this to transmission of an impulse from nerve fiber to muscle fiber. Is transmission of the impulse across a synapse one-way? What role does calcium play in the release of a neurotransmitter? → Through Neurotransmitters
Calcium has to go into the synapse to stimulate the vessels to open.
Describe the importance of the Schwann cells in regeneration of the nerve fiber following injury. → Schwann Cell wraps around the axon to form the myelin sheath.
Neurilemma is the plasma membrane of a neuron
Ranvier is the space between mylination
Motor neurons are located where? Sensory neurons are located where? → PNS
Everywhere except the brain