Your nervous system is organized into two broad anatomical divisions: the central nervous system (consisting of the brain and spinal cord) and the peripheral nervous system (PNS). Your PNS is further organized into two functional divisions. If you tap your knee, the signal to act is carried via your   to the muscles in your knee. In contrast, the signals that pass via the   are involuntary and act primarily to regulate your body's internal environment. This involuntary nerve system is further organized into three divisions. If you need a sudden burst of energy, your   is activated to help you act quickly. In contrast, if you are relaxing and conserving energy, then it is your   that is primarily in action. The third division is your   which helps control the components of the digestive system.

Sense of smell, also known as olfaction, is the ability to perceive and interpret odours. When a chemical molecule interacts with an odour-receptor protein located on the sensory neuron in the nose, an action potential is triggered and sent along the axon. The interaction between a chemical molecule and an odour-receptor protein will first initiate the movement of _____A______ ______B_____ the _____C______ of the _____D_____ neuron. Using the numbers given below, identify A to D. A B C D Chlorine ions Potassium ions Sodium ions Into Out of Axon Dendrite Axon terminal Nodes of Ranvier Interneuron Motor neuron Sensory neuron A: AnswerB: AnswerC: AnswerD: Answer

Match the following components of the nervous system with their correct descriptions   Interneurons   Sensory neurons   Motor neurons   Nerve net   Neurons that send signals to effector cells like muscles and glands that affect change              Neurons that carry signals from the environment to the central nervous system from the peripheral nervous system              Neurons that transmit signals between other neurons, part of the CNS        A diffuse arrangement of neurons that are found in jellyfish and other cnidarians

Which of the following would occur if a neuron was experimentally stimulated simultaneously at both ends? The action potentials would pass in the middle and travel to the opposite ends The action potentials would stop as they meet in the middle. The stronger action potential would override the weaker action potential. Summation would occur when the action potentials meet in the middle, resulting in a larger action potential.

When they are not being stimulated, neurons have an electrical charge across their membranes called the resting potential. This potential is______ charged inside. When a neuron receives a sufficiently large stimulus, and reaches a potential called the_______ , it produces an action potential. This causes the neuron to become_____ charged inside.

Which of the following is true regarding the difference between graded and action potentials? a.) Action potential occur only when the surface of the neuron is myelinated, but graded potentials occur in both in both myelinated and non-myelinated neurons.  b.) The magnitude of action potential depends on the magnitude of the stimulus, whereas graded potentials are all or none.  c.) The magnitude of graded potential depends on the magnitude of the stimulus, whereas action potentials are all or none.

What terms denotes a sudden change (depolarization and repolarization) in the electrical properties of the neuron membrane? Action potential  Synaptic transmission  Event-related potential Postsynaptic potential ------------------------------------ You step on a brick, ouch. What type of nerve will bring the signal from your foot to your brain? Somatic afferent  Somatic efferent  automatic afferent  automatic afferent ---------------------------------------------- A given neurotransmitter is inhibitory. What might its receptors do?   Allow positive ions to enter the cell Allow negative ions to enter the cell  Allow positive ions to leave the cell B and C

You have isolated a neurotoxin from a newly discovered snake species. When you administer the toxin to brain tissue, you can no longer record an excitatory postsynaptic potential after you experimentally stimulate the presynaptic neuron. a. Draw what the experimental setup would look like. Also include a picture of the recording you would get from the postsynaptic neuron after the  presynaptic stimulation before and after the administration of the toxin. Label your figures completely and label all axes.

Which of the following is NOT an example of communication that happens from one neuron to another neuron? A. Endocrine signaling (ex. hormones secreted into the blood stream travel and bind to receptors on dstant cells). B. Retrograde neurotransmission (ex.the dendrite releases a neuroactive substance that binds to receptors on the axon terminal of a presynaptic neuron). C. Electrical communication via propagation of action potential from one node of ranvier to the next node of ranvier. D. Volume transmission (ex. neuropeptides diffuse away from the synapse and bind to receptors on adjacent cells) E. Electrical communication through gap junctions.

If you inhibit the closing of sodium channels what do you predict the effect on neuronal function will be? If you inhibit the closing of sodium channels what do you predict the effect on neuronal function will be? Hyper-excitability: more sodium ions flow into the cell, causing neurons to fire more readily Hypo-excitability: more sodium ions flow into the cell, causing neurons not to fire as readily Less sodium is pumped out of the cell, slowing down return to the resting state Sodium ions are toxic to neurons, leading to cell proliferation