Which of the following is (are) associated with most polyadenylation events?

a. cleavage of the 5´ end of the RNA molecule

b. an assembly of a large, multiprotein complex

c. the AAUAAA site upstream of where polyadenylation will occur

d. a GU-rich or U-rich region near the cleavage site

e. slow addition of A residues followed by rapid addition of 200 to 250 more A residues

#Question id: 11187

#Unit 7. System Physiology – Animal

Refer to the following graph of an action potential to answer the question.

The membrane's permeability to sodium ions is greatest at label ________.

#Question id: 11188

#Unit 7. System Physiology – Animal

Refer to the following graph of an action potential to answer the question.

The minimum graded depolarization needed to operate the voltage-gated sodium and potassium channels is indicated by the label ________.

#Question id: 11189

#Unit 7. System Physiology – Animal

Refer to the following graph of an action potential to answer the question.

At label ________, the cell is not hyperpolarized; however, repolarization is in progress, as the sodium channels are inactivated or becoming inactivated, and many potassium channels have opened.

#Question id: 11190

#Unit 7. System Physiology – Animal

For a neuron with an initial membrane potential at -70 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in the ________.

#Question id: 11191

#Unit 7. System Physiology – Animal

Opening all of the sodium channels on an otherwise typical neuron, with all other ion channels closed (which is an admittedly artificial setting), should move its membrane potential to ________.

#Question id: 11192

#Unit 7. System Physiology – Animal

A graded hyperpolarization of a membrane can be induced by ________.