Lab 3 Flashcards
In addition to the skin receptors what brain structure also has thermoreceptors?
the hypothalamus because it regulates temperature.
What is the pathway of neurons btwn thermoreceptors in the skin and the cerberal cortex? (simple w/out memb pots)
thermoreceptors –> 1st order neuron –> second order neuron –> third order neuron –> postcentral gyrus (which is in the cerebral cortex).
Where in the cerebral cortex is sensory info interpreted?
somatosensory cortex in the postcentral gyrus.
What is the pathway of neurons from the primary motor cortex to the effectors? (simple)
2 pathways; direct/corticospinal= primary motor cortex –> UMN –> SC –> LMN –> skel mm.
indirect= primary motor cortex –> brain stem nuclei –> UMN –> SC –> LMN –> skel mm.
What is the pathway btwn the CNS and the effectors in the ANS?
CNS –> preganglionic neuron –> synapse at ganglion (release nt) –> postganglionic neuron –> synapse at effector (release nt) –> effector.
What would damage to the motor cortex of the left frontal lobe affect?
controls voluntary mvmts so will cause paralysis or loss of motor skills on right side.
What would damage to the postcentral gyrus of left hemisphere do?
processes sensory info so affects touch temp pain.
What would damage to the cerebellum do?
maintains homeostasis so would have irregular HR, disrupt body temp, and troubles with balance and coordination.
What would damage to the hypothalamus do?
involved in homeostasis, but could die if not regulated. lose control of cardiac fxns, endocrine syst, etc.
In a neuron, a change in membrane potential from -70mV to -60mV; a) could occur on dendrites of multiplolar neurons b) is an example of hyperpol of the memb c) is depol that may occur during the production of an EPSP d) means that the membrane potnetial is more neg than in the resting neuron e) is described by a) and c)
e) is described by a) and c)
Which of the following statements about the neuron is incorrect? a) during the depol phase of an action potential, Na voltage-gated channels open. b) a resting neuron has a lower Na conc inside than outside the cell c) K diffusing into a cell and intracellular non-diffusible organic ions are mainly responsible for a RMP. d) opening of K voltage-gated channels is one factor responsible for the repolarization of the axonal membrane during an AP. e) the Na/K pump is used in cells to maintain a conc grad of Na and K, which helps to establish the RMP.
c) K diffusion into a cell and intracellular non-diffusable organic ions are mainly responsible for a RMP. (bc K diffuses out of cell)
During an absolute refractory period; a) a second AP cannot be initiated. b) a stronger than normal stimulus will produce an action potential. c) an increase in K permeability can occur. d) a) and c) occur. e) all of the above occur.
d) a) and c) occur. bc no APs can be initiated during this period, and more K channels open in repol, increasing the permeability.
An IPSP; a) produces postsynaptic depol. b) could result from an increase in chloride permeability into the cell. c) is produced when ACh is released at a neuromuscular junction. d) obeys the all-or-none principle. e) is described by none of the above.
b) could result from an increase in chloride permeability into the cell. (bc Cl channels open)
Which of the following statements related to sensory and motor phys is correct? a) high core body temp is detected by thermoreceptors in the medulla oblongata b) the warmth of the sun on your skin is perceived in the precentral gyrus of the brain. c) the nt epinephrine is released by sympathetic neurons to stimulate sweat glands. d) sensory signals for general senses travel along preganglionic and postganglionic neurons to the postcentral gyrus of the brain. e) the somatic motor system sends signals through upper and lower motor neurons that innervate skeletal mms.
e) the somatic motor system sends signals through upper and lower motor neurons that innervate skeletal mms.
Which of the following is not involved in establishing the resting membrane potential? a) higher permeability of the cell membrane to sodium than potassium b) Na/K ATP-ase pump c) non-gated K channels (K leakage channels) d) large negatively charged ions inside the cell.
a) higher permeability of the cell membrane to sodium than potassium
What characteristics of an axon would allow an AP to travel the fastest? a) myelinated, small diameter b) myelinated, large diameter c) unmyelinated, small diameter d) unmyelinated, large diameter
b) myelinated, large diameter
After having a stroke, a patient no longer has feeling in the right side of their body. in which of the following brain areas did the stroke likely occur? a) motor cortex of the left frontal lobe b) postcentral gyrus of the left hemisphere c) cerebellum d) hypothalamus
b) postcentral gyrus of the left hemisphere
