chapter 4 - How Do Neurons Use Electrical Signals to Transmit Information? Flashcards
Approximately \_\_\_\_\_\_ people have a seizure at some point in their lifetime. A) 1 in 5 B) 1 in 20 C) 1 in 100 D) 1 in 1000
B) 1 in 20
Erica is an 18-year-old and in her first year of university. One day while she was watching a video in class, Erica started to hear what she thought was music playing. Suddenly she began shaking in her seat and fell to the floor. After the incident ended, one of her classmates helped her to the campus medical center, where she was later diagnosed as having: A) Huntington’s disease. B) Parkinson’s disease. C) epilepsy. D) myasthenia gravis.
C) epilepsy.
- The three symptoms that are common to many forms of epilepsy are:
A) abnormal vocalizations, an aura, and loss of consciousness.
B) headache, abnormal movements, and loss of consciousness.
C) an aura, abnormal movements, and loss of consciousness.
D) abnormal vocalizations, hallucinations, and an aura.
C) an aura, abnormal movements, and loss of consciousness.
René Descartes believed that \_\_\_\_\_\_ carried signals through the nervous system. A) neurons B) phlegm C) the pineal gland D) cerebrospinal fluid
D) cerebrospinal fluid
The technique of electrical stimulation was first discovered by: A) Luigi Galvani. B) René Descartes. C) Gustave Fritsch and Edward Hitzig. D) David Ferrier.
A) Luigi Galvani.
Electricity is a flow of electrons from a body that contains a higher charge (more electrons) to a body that has a lower charge (fewer electrons). The body containing the higher electrical charge is called a: A) positive pole. B) negative pole. C) dipole. D) ground pole
B) negative pole.
Another term for volts is: A) electrical potential between two poles. B) current flow. C) amps. D) current flow and amps.
A) electrical potential between two poles.
In a now-famous experiment Fritsch and Hitzig discovered that electrical stimulation of the neocortex led to: A) hearing sounds. B) movements. C) seizures. D) seeing patterns.
B) movements.
Roberts Bartholow is remembered for being the first person to stimulate the brain(s) of a: A) dog. B) rabbit. C) human. D) a dog and a rabbit.
C) human.
When Richard Caton first measured fluctuations on a voltmeter from electrodes placed on the scalp of a human subject, he was recording what we now call: A) the electroencephalogram. B) the action potential. C) the magnetoencephalogram. D) axonal conductance.
A) the electroencephalogram.
An electroencephalogram, or EEG, can theoretically be recorded by: A) a voltmeter. B) a current meter. C) an amp meter. D) both a voltmeter and a current meter.
A) a voltmeter
12. Measuring the speed of information flow in a nerve was first performed by: A) Hermann von Helmholtz. B) Wilder Penfield. C) Eduard Hitzig. D) Gustave Fritsch
A) Hermann von Helmholtz
Neurons in most animals, including humans, are approximately:
A) 1 to 20 thousandths of a millimeter in diameter.
B) 50 to 100 thousandths of a millimeter in diameter.
C) 500 to 700 thousandths of a millimeter in diameter.
D) up to a millimeter in diameter
A) 1 to 20 thousandths of a millimeter in diameter
Because the giant axons of the squid are nearly \_\_\_\_\_\_ in diameter, they were used to record electrical activity in neurons for the first time. A) 1 centimeter B) 1 millimeter C) 5 millimeters D) 0.1 millimeter
B) 1 millimeter
Microelectrodes can: A) be made from glass. B) be made from wire. C) have a tip as small as 0.001 millimeter. D) All of the answers are correct.
D) All of the answers are correct
The ability to record from single neurons was made possible by the invention of:
A) the electroencephalogram.
B) the oscilloscope.
C) the microelectrode.
D) both the oscilloscope and the microelectrode.
D) both the oscilloscope and the microelectrode
The patch technique involves:
A) placing the tip of a microelectrode on an axon.
B) recording between two microelectrodes, one inside the axon and the other outside.
C) placing the tip of the microelectrode in an axon and applying some back suction.
D) placing the tips of the two microelectrodes in an axon and recording between them.
C) placing the tip of the microelectrode in an axon and applying some back suction
In order to measure the voltage across the cell membrane you would normally:
A) insert two electrodes into the axon and measure the voltage difference.
B) place one electrode on the outer surface of an axon’s membrane and another inside the axon
and measure the voltage difference.
C) place two electrodes on the outer surface of the axon’s membrane and measure the voltage
difference.
D) All of the answers are correct.
B) place one electrode on the outer surface of an axon’s membrane and another inside the axon
and measure the voltage difference
When a substance moves from an area of high concentration to an area of low concentration, it is an example of a(n): A) concentration gradient. B) voltage gradient. C) ionic translocation. D) None of the answers is correct.
A) concentration gradient
The movement of ions from an area of high concentration to an area of low concentration is called: A) a concentration gradient. B) a voltage gradient. C) diffusion. D) ionic translocation.
C) diffusion
The notion that opposites attract is an analogy that best describes: A) a concentration gradient. B) a voltage gradient. C) diffusion. D) All of the answers are correct.
B) a voltage gradient
If a small amount of dye is placed in a beaker of water, it will flow away from the initial point of contact. The ensuing process illustrates: A) diffusion. B) concentration. C) charge. D) electrostatic pressure
A) diffusion
Channels in the cell membrane are formed by: A) sodium ions. B) potassium ions. C) protein molecules. D) lipids.
C) protein molecules
Which of the following is not involved in producing the resting potential? A) potassium ions B) chloride ions C) calcium ions D) sodium ions
C) calcium ions
The resting potential:
A) is –70 mV in all species.
B) can vary from –40 mV to –90 mV within a species.
C) can vary from –40 mV to –90 mV between species.
D) None of the answers is correct.
C) can vary from –40 mV to –90 mV between species
A change in the resting potential from –70 mV to –73 mV is called:
A) depolarization.
B) hyperpolarization.
C) graded excitatory potential.
D) nothing, as these changes occur spontaneously.
B) hyperpolarization
When the neuron is at rest, \_\_\_\_\_\_ channels are normally closed, whereas \_\_\_\_\_\_ is free to enter and leave the cell. A) K+; Na+ B) Cl–; Na+ C) Na+; K+ D) K+; Cl–
C) Na+; K+
Which of the following is not true?
A) The cell membrane is semipermeable, so it keeps in large negatively charged protein
molecules.
B) The membrane keeps out Na+ and allows K+ and C1– to pass more freely.
C) The membrane has a sodium–potassium pump that removes potassium from inside the cell
and replaces it with sodium.
D) The summed charges of the unequally distributed ions leave the inside of the membrane at
–70 mV relative to the outside. This is the cell’s resting potential.
C) The membrane has a sodium–potassium pump that removes potassium from inside the cell
and replaces it with sodium
Large protein anions are: A) manufactured by glial cells. B) manufactured within a neuron. C) transported to a neuron by glial cells. D) not part of a neuron.
B) manufactured within a neuron
There are approximately \_\_\_\_\_\_ K+ ions inside the cell membrane compared to outside the cell. A) 20 times more B) 2 times more C) one-tenth as many D) equal concentrations of
A) 20 times more
The negative charge inside of the cell membrane is largely a product of the presence of: A) negatively charged potassium ions. B) negatively charged sodium ions. C) negatively charged protein anions. D) All of the answers are correct.
C) negatively charged protein anions
Small voltage fluctuations in the cell membrane that occur near the vicinity of the axon are called: A) action potentials. B) graded potentials. C) ion fluctuations. D) nerve impulses.
B) graded potentials
The sodium–potassium pump:
A) continuously exchanges three intracellular Na+ for two extracellular K+.
B) continuously exchanges three intracellular K+ for two extracellular Na+.
C) continuously exchanges three extracellular Na+ for two intracellular K+.
D) intermittently exchanges three intracellular K+ for two extracellular Na+.
A) continuously exchanges three intracellular Na+ for two extracellular K+