Which of the following situations occurs in electrically excitable cells?
A. Ligand-gated Na+ channels are opened by high extracellular Ca2+ levels.
B. When Na+ channels open, K+ channels close.
C. Proteins tend to diffuse out of the cell.
D. The sodium-potassium pump moves Na+ into the cell.
E. Depolarization causes voltage-gated Na+ channels to open.
Answer: E
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Which of the following characterizes Type I but not Type II diabetes mellitus?
a. Hyperglycemia b. Lack of insulin c. Polyuria and polydipsia d. It can usually be successfully managed by dietary control and weight reduction without the necessity of insulin injections. e. It generally arises in adulthood.
What type of gland does not have ducts?
A. holocrine B. apocrine C. endocrine D. exocrine E. merocrine
Like proteins, eicosanoids are synthesized on ribosomes in a process that involves transcription and translation.
Answer the following statement true (T) or false (F)
During exercise, our vessels constrict and vessel radius decreases. What impact does a decreased vessel radius have on blood flow?
A) Blood flow remains the same. B) Blood flow decreases. C) Blood flow increases. D) Vessel radius has no impact on blood flow.