Term
| In humans, information is encoded as ___________ signals in the nervous system and as chemical signals in the ____________ system. |
|
Definition
|
|
Term
| Regulation requires ____________. |
|
Definition
|
|
Term
| The principal cells of the nervous system are ___________. |
|
Definition
|
|
Term
| A key feature of neurons is that their __________ membranes can ______________________________________________________. |
|
Definition
| plasma; generate and propagate electrical signals. |
|
|
Term
| The ____________ are bush like projections that bring information from other neurons or sensory cells to the cell body. |
|
Definition
|
|
Term
| The _________ carries information away from the cell body. |
|
Definition
|
|
Term
| The ___________________, which are swellings at the tips of the axon, are involved in communicating the information in electrical signals to other neurons, muscle cells, or gland cells. |
|
Definition
|
|
Term
| The _______________ is the point of communication with adjacent cells. |
|
Definition
|
|
Term
| The human brain may contain ______ billion neurons, and each neuron may make synapses with _________ or more other neurons. |
|
Definition
|
|
Term
| The ___________ system contains glial cells. |
|
Definition
|
|
Term
| _________________ serve many important "housekeeping" functions, such as supply the neurons with nutrients and maintaining the proper ionic environment around the neurons. |
|
Definition
|
|
Term
| Do glial cells generate or propagate action potentials? |
|
Definition
|
|
Term
| Pumps require ___________. |
|
Definition
|
|
Term
| The plasma membrane of a neuron contains protein molecules that act as ___________ to move ions against their concentration gradients. |
|
Definition
|
|
Term
| The key pump is the __________________ pump. |
|
Definition
|
|
Term
| The plasma membrane contains protein molecules that act as ____________ allowing ions to pass through by diffusion. |
|
Definition
|
|
Term
| Some channels are _________, in that they open under some conditions but not others. |
|
Definition
|
|
Term
| ______________ channels open or close in response to a change in the voltage across the membrane. |
|
Definition
|
|
Term
| __________________ channels open or close in response to specific chemicals that bind directly to the channel protein or to receptors that alter the channel protein. |
|
Definition
|
|
Term
| Neurons have an excess of ____________ electrical charge. |
|
Definition
|
|
Term
| The ___________ potential (-60 mV) results primarily from the permeability of the plasma membrane to potassium ions. |
|
Definition
|
|
Term
| Potassium gives rise to _________ potential. |
|
Definition
|
|
Term
| The _________________________ is the point at which diffusion of potassium ions out of the neuron due to the concentration gradient is ____________ by movement of potassium ions into the neuron due to the _______________________. |
|
Definition
| potassium equilibrium potential; balanced; negative electrical potential |
|
|
Term
| The ___________________________ closely approximates the resting potential of a typical neuron. |
|
Definition
| potassium equilibrium potential |
|
|
Term
| The difference in electrical charge across the plasma membrane of a neuron means that the membrane is ___________ (has a charge). |
|
Definition
|
|
Term
| The basic mechanism by which electrical signals are generated and propagated by neurons involves changes in the _____________ of the plasma membrane. |
|
Definition
|
|
Term
| Neurons transmit electrical signals via _____________________, which are sudden and major changes in membrane potential that last for only 1-2 milliseconds. |
|
Definition
|
|
Term
| ___________________ may be conducted along neurons at speeds up to 100 m/s |
|
Definition
|
|
Term
| At resting potential, these kind of channels are mostly closed: |
|
Definition
| voltage-gated sodium channels |
|
|
Term
| If a _________________ ______________ the membrane, activation gates in the sodium channels open briefly, allowing sodium ions to move into the cell along an ________________ gradient. |
|
Definition
| synaptic input depolarizes; electrochemical |
|
|
Term
| If sufficient numbers of sodium channels open, the membrane potential rises rapidly from ______ mV to about ______ mV. |
|
Definition
|
|
Term
| What two factors cause the axon to return to its resting potential? |
|
Definition
1. Inactivation gates in the sodium channels close.
2. Voltage-gated potassium channels open. |
|
|
Term
| As a result of an axon returning to resting potential, the membrane potential returns to a _____________ value. |
|
Definition
|
|
Term
| How many directions does a neuron transfer information? |
|
Definition
|
|
Term
| When one part of the membrane generates/"fires" an _______________, the adjacent regions of the membrane become _________________ because of the spread of local _______________. |
|
Definition
| action potential; depolarized; electrical current |
|
|
Term
| When the inactivation gates of sodium channels close, they remain closes for a few milliseconds before they spontaneously open again. This period is known as the ____________. |
|
Definition
|
|
Term
| Rapid propogation is facilitated by the presence of __________________. |
|
Definition
|
|
Term
| For much of their length, axons are covered by membraneous sheaths of ____________. |
|
Definition
|
|
Term
| The ____________ insulates axons, such that electric charges cannot accumulate or cross the plasma membrane. |
|
Definition
|
|
Term
| At nodes of Ranvier, _____________ can be generated. |
|
Definition
|
|
Term
| ________________ along a myelinated axon is much faster than continuous impulse conduction along an unmyelinated axon. |
|
Definition
| Saltatory impulse conduction |
|
|
Term
| Action potentials only happen at _________. |
|
Definition
|
|
Term
| Neurons can interact with __________, ____________, or ___________. |
|
Definition
| other neurons; muscles cells; gland cells |
|
|
Term
| The interactions of neurons are controlled at the ___________, which are the junctions where one cell influences another cell directly. |
|
Definition
|
|
Term
| Communication across synapses are ____________. |
|
Definition
|
|
Term
| _______________ is a common neurotransmitter, and is involved in synapses between motor neurons and skeletal muscle cells. |
|
Definition
|
|
Term
| Some simple amino acids, such as ______________ and _________________ acid, are common neurotransmitters in the synapses between neurons in the central nervous system. |
|
Definition
| glutamate glycine; gamma-aminobutyric |
|
|
Term
| Some simple peptides, such as ____________, function as neurotransmitters, especially in _____________ neurons involved in pain pathways. |
|
Definition
|
|
Term
| ______________ information crosses the synapse in only one direction, from the ____________ to the _____________ cell. |
|
Definition
| Chemical; presynaptic; postsynaptic |
|
|
Term
| ____________ of the terminal membrane causes voltage-gated calcium channels to open. |
|
Definition
|
|
Term
| __________ ions enter the presynaptic cell, and trigger the fusion of vesicles containing _____________ (the neurotransmitter) with the plasma membrane. |
|
Definition
|
|
Term
| If sufficient ________________ is released by the presynaptic cell, the spreading depolarization will result in an _________________. |
|
Definition
| acetylcholine; action potential |
|
|
Term
| A popular drug used is __________. It binds to certain types of acetylcholine receptors, but does not activate them. Thus the skeletal muscle cells in animals poised by this drug do not respond to neuron activation. |
|
Definition
|
|
Term
| Synapses between motor neurons and skeletal muscle cells are always _____________, in that the neurotransmitter depolarizes the plasma membrane of the postsynaptic cell. |
|
Definition
|
|
Term
| The central nervous system consists of the ____________ and the _______________. |
|
Definition
|
|
Term
| Synapses between neurons, such as those in the CNS, can be either _____________ or ________________. |
|
Definition
|
|
Term
| In _____________ synapses, the neurotransmitter _______________, rather than depolarizes, the plasma membrane of the postsynaptic cell. |
|
Definition
| inhibitory; hyperpolarizes |
|
|
Term
| __________ is considered to be an inhibitory neurotransmitter in the CNS. |
|
Definition
|
|
Term
| A neuron may have many __________. |
|
Definition
|
|
Term
| Axon terminals from many other neurons may form ___________ with dendrites and with the ________________. |
|
Definition
|
|
Term
| The axon terminals of different presynaptic neurons may store and release different ___________________. |
|
Definition
|
|
Term
| The _______________ of the dendrites and cell body of the postsynaptic neuron may have receptors for a variety of neurotransmitters. |
|
Definition
|
|
Term
| At any one time, a _____synaptic neuron may receive a variety of different chemical signals, some of where are ____________ and some of which are ____________. |
|
Definition
| post; excitatory; inhibitory |
|
|
Term
| Excitatory neurotransmitters give rise to __________________ (EPSP), whereas inhibitory neurotransmitters give rise to an ___________________ (IPSP). |
|
Definition
| excitatory postsynaptic potential; inhibitory postsynaptic potential. |
|
|
Term
| The summation of ________ and __________ determines whether or not a given post synaptic neuron generates an action potential. |
|
Definition
|
|
Term
| The __________________ of EPSPs and IPSPs is the major mechanism by which the CNS integrates information. |
|
Definition
|
|
Term
| The control center for the nervous system is the ________, which governs virtually every facet of our lives from birth to death. |
|
Definition
|
|
Term
| What are the key regions the adult brain contains? |
|
Definition
1. the brain stem, which includes the medulla, pons, cerebellum, and midbrain
2. the diencephalon, which includes the thalamus and hypothalamus
3. the telecephalon, or cerebrum |
|
|
Term
| The ____________ plays key roles in sensory perception, learning, memory, and consciousness. |
|
Definition
|
|
Term
| The cerebrum consists of _____ hemispheres, each of which is covered by a sheet of grey matter known as the _________________. |
|
Definition
|
|
Term
| Information from the auditory system is received and processed in the upper region of the _______________. |
|
Definition
|
|
Term
| Information from the olfactory system is received and processed in the _______________ associated with the ___________. |
|
Definition
| olfactory bulb; frontal lobe |
|
|
Term
| Information from the ___________ system is received and processed in the occipital lobe. |
|
Definition
|
|
Term
| Within the ___________________, muscles in different parts of the body are controlled by different zones or regions. |
|
Definition
|
|
Term
| A _______________ scan of the brain can visualize levels of ______________, and thus identify areas of the brain in a particular function is centered. |
|
Definition
| positron emission (PET); radioactivity |
|
|
Term
| During a particular brain function, areas of the ___________ cortex that have a higher metabolic use of _____________ exhibit high levels of radioactivity. |
|
Definition
|
|
Term
| A ___________ of the brain can visualize levels of radioactivity, and thus identify areas of the brain in a particular function. |
|
Definition
|
|
Term
| The functions of _________ words, __________ words, and _________ words are centered in different areas of the brain. |
|
Definition
| viewing; hearing; speaking |
|
|
Term
| In humans, ______________ cells convert or transduce ___________ and __________ stimuli from the environment into signals that are transmitted to other parts of the _____________ system. |
|
Definition
| sensory; physical; chemical; nervous |
|
|
Term
| The ________________ enhance the ability of the sensory cells to collect and amplify stimuli from the environment. |
|
Definition
|
|
Term
| Most sensory cells are _________________. |
|
Definition
|
|
Term
| The plasma membranes of sensory cells contain _______________. |
|
Definition
|
|
Term
| When a _________________ is activated by a specific stimulus, it opens or closes ion channels in the plasma membrane by one of the several mechanisms. |
|
Definition
|
|
Term
| An activated __________ protein may be part of an ion channel, and may open or close the channel directly by changes in its _______________ or 3D shape. |
|
Definition
|
|
Term
| _______________ respond to changes in pressure. |
|
Definition
|
|
Term
| An activated ___________ protein may act indirectly by initiating a __________________________ that controls the opening or closing of an associated ion channel in the plasma membrane. |
|
Definition
| receptor; signal transduction cascade |
|
|
Term
| _______________ and _______________ respond to chemical and light stimuli, respectively (Think ion channels), |
|
Definition
| Chemoreceptors; photoreceptors |
|
|
Term
| The opening or closing of ion channels by the activated receptor proteins alters the membrane potential of the sensory cell, resulting in a ___________________. |
|
Definition
|
|
Term
| The _______________ must be converted into an ______________ in order for the signal from the sensory cell to be propagated in the nervous system. |
|
Definition
| receptor potential; action potential |
|
|
Term
| In cells that are capable of generating action potentials, the receptor potential spreads to a region of the plasma membrane that contains _____________________ channels. |
|
Definition
|
|
Term
| In sensory cells that lack the ability to generate action potentials, the receptor potential spreads to a ________________ region of the plasma membrane and induces the release of a ___________________. |
|
Definition
| presynaptic; neurotransmitter |
|
|
Term
| We sense sound via our ____________ system, with the key sensory organ being the _______. |
|
Definition
|
|
Term
| The ear ________ (the prominent structure on the side of our heads) collects pressure waves (or sound waves) and directs them into the ________________. |
|
Definition
|
|
Term
| The eardrum, or ______________, covers the ends of the auditory canal, and vibrates in response to pressure waves traveling down the canal. |
|
Definition
|
|
Term
| The eardrum, or ______________, covers the ends of the auditory canal, and vibrates in response to pressure waves traveling down the canal. |
|
Definition
|
|
Term
| On the other side of the tympanic membrane (opposite of the canal) is the ___________________. |
|
Definition
|
|
Term
| The middle ear contains _____ specialized bones known as ___________. |
|
Definition
|
|
Term
| The ____________ amplify and transmit the vibrations of the tympanic membrane to the _____________, a flexible membrane that separates the middle ear from the _________________. |
|
Definition
| ossicles; oval window; fluid-filled inner ear |
|
|
Term
| The ossicles are capable of amplifying the force of the vibrations by about _______-fold. |
|
Definition
|
|
Term
| In the fluid-filled inner ear, vibrations of the oval window result in pressure waves that are ultimately detected by __________________. |
|
Definition
|
|
Term
| The fluid-filled inner ear consists of a long, tapered, coiled chamber known as the _____________. |
|
Definition
|
|
Term
| The cochlea contains _____ parallel canals separated by _____ membranes, one of which is the ____________. |
|
Definition
|
|
Term
| Located on the basilar membrane is the specialized organ of __________, which contains sensory cels known as ________ cells. |
|
Definition
|
|
Term
| The hair cells are ________________. |
|
Definition
|
|
Term
| Projecting from the surface of the hair cells are _______________. |
|
Definition
|
|
Term
| The stereocilia are in contact with a rigid shelf that overhangs the organ of Corti, known as the ______________________. |
|
Definition
|
|
Term
| Pressure waves in the ____________ from vibrations of the oval window cause the basilar membrane to flex. |
|
Definition
|
|
Term
| When the basilar membrane flexes, the ______________ presses against the rigid _____________ membrane and bend. |
|
Definition
|
|
Term
| As the stereocilia bend, they activate _________________ in the plasma membranes of the hair cells. |
|
Definition
|
|
Term
If the plasma membranes are ___________ by the activated receptor proteins, the hair cells release a _____________ that causes action potentials to be generated and propagated by associated neurons.
The latter neurons form part of the ________________ that transmits information to the brain. |
|
Definition
| depolarized; neurontransmitter; auditory nerve |
|
|
Term
| What are two general ways does impaired hearing arise? |
|
Definition
| Conduction deafness and nerve deafness |
|
|
Term
| _________________ is caused by the loss of function of the timpani membrane or the ossicles of the air-filled middle ear. |
|
Definition
|
|
Term
| _____________is caused by damage to the inner ear or the auditory nerve. |
|
Definition
|
|
Term
| We sense odor with the _____________ system, with the key sensory organ being the _______. |
|
Definition
|
|
Term
| The sensory cells for smell are neurons embedded in a layer of _______________ cells at the top of the ___________ layer. |
|
Definition
|
|
Term
| The dendrites of the sensory cells end in __________________ at the surface of the nasal epithelium. |
|
Definition
|
|
Term
| The axons of the sensory cells project into the _______________ of the brain. |
|
Definition
|
|
Term
| The sensory cells are _________________. |
|
Definition
|
|
Term
| What is the activation route for the propagation of an action potential in the sensory cell? |
|
Definition
> receptor protein > G protein > adenylyl cyclase > AMP ("second messenger") = sodium channels in the plasma membrane
>: activates, =: binds |
|
|
Term
| The diversity of receptor proteins in the olfactory system of humans is large, enabling discrimination among a wide variety of ____________. |
|
Definition
|
|
Term
| We sense light via our __________ system, with the key sensory organ being the ______. |
|
Definition
|
|
Term
| At the front of the eye, the connective tissue forms the transparent _____________, through which light passes to enter the eye. |
|
Definition
|
|
Term
| To the inside of the cornea is the _________ which controls the amount of light reaching the layer of sensory cells in the _____________ at the back of the eye. |
|
Definition
|
|
Term
| The central opening of the iris is the _________ when the iris constricts, as in bright light, the pupil is __________. |
|
Definition
|
|
Term
| To the inside of the iris is the ________, which is made of the _____________ proteins. |
|
Definition
|
|
Term
| The sensory cells of the eye are ______________, and contain the receptor protein, ___________. |
|
Definition
| photoreceptors; rhodopsin |
|
|
Term
| One type of photoreceptor is the ________ cell. |
|
Definition
|
|
Term
| A _____________ is a modified neuron with a highly specialized structure. |
|
Definition
|
|
Term
| Each rod cell has an __________ segment, an __________ segment, and a ____________ terminal. |
|
Definition
|
|
Term
The ______________ of a rod cell contains a stack of plasma membrane discs densely packed with rhodopsin.
And what is the function of those discs? |
|
Definition
outer segment
To capture photons of light energy passing through the rod cell. |
|
|
Term
| The _____________ of a rod cell contains the nucleus and abundant mitochondria. |
|
Definition
|
|
Term
| The _______________ of a rod cell is where the rod cell communicates with other neurons via neurotransmitters. |
|
Definition
|
|
Term
| The ___________ is a modified neuron with a specialized structure. |
|
Definition
|
|
Term
| ______________ are very sensitive to light, and thus are well-suited for vision under lower light conditions. |
|
Definition
|
|
Term
| ______________ are less sensitive to light, and thus function well under high light conditions. |
|
Definition
|
|
Term
| ____________ are responsible for color vision in humans. |
|
Definition
|
|
Term
| The human _______________ contains ____ types of cone cells, which differ in the wavelengths of visible light that they absorb. |
|
Definition
|
|
Term
| Rhodopsin consists of both an ___________ and a light-absorbing component, ________________. |
|
Definition
| opsin protein; 11-cis-retinal |
|
|
Term
| The ______________ is cradled in the center of the opsin protein, and is bound to it. |
|
Definition
|
|
Term
| When 11-cis-retinal absorbs a photon of light energy, it changes into a different isomer (or form) of retinal, known as _______________. |
|
Definition
|
|
