The plasma membrane of an excitable cell is more permeable to potassium ions because
A. of its positive electrical charge.
B. there are more leak ion channels for K+ than Na+.
C. protein molecules cannot exit through the cell membrane.
D. calcium ions block Na+ and Cl- channels.
E. there are more gated channels for K+.
B
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The inner ear includes which of the following?
A) pinna B) tympanic membrane C) external auditory canal D) cochlea E) ossicles
Match each of the following terms with its correct definition.
a. 1 b. 2 c. 3 d. 4 e. 5 f. 6 g. 7 h. 8 i. 9 j. 10 k. 11 1. _____ duodenum 2. _____ ileocecal valve 3. _____ mouth 4. _____ pyloric sphincter 5. _____ esophagus 6. _____ ascending colon 7. _____ stomach 8. _____ transverse colon 9. _____ ileum 10. _____ pharynx 11. _____ jejunum
Which of the following functional groups of organic compounds link molecules through dehydration synthesis?
A) amino group B) hydroxyl group C) phosphate group D) carboxyl group E) none of the above
An inhibitory postsynaptic potential results from the opening of ______.
Fill in the blank(s) with the appropriate word(s).