The second messenger mediating the effects of norepinephrine on the heart would be ________.
A. increased intracellular Ca2+
B. decreased Ca2+
C. decreased intracellular cyclic AMP
D. increased cyclic AMP
Answer: D
You might also like to view...
Which of the following represents the correct pathway for sperm during ejaculation?
A. Ductus deferens - ejaculatory ducts - rete testes - efferent ductules - epididymis - seminiferous tubules - prostatic urethra - penile urethra - outside the body B. Rete testes - efferent ductules - epididymis - seminiferous tubules - ductus deferens - ejaculatory ducts - prostatic urethra - penile urethra - outside the body C. Seminiferous tubules - ductus deferens - ejaculatory ducts - rete testes - efferent ductules - epididymis - prostatic urethra - penile urethra - outside the body D. Seminiferous tubules - rete testes - efferent ductules - epididymis - ductus deferens - ejaculatory ducts - prostatic urethra - penile urethra - outside the body
In the centrifuged sample of blood illustrated, number 2 indicates
A. platelets. B. leukocytes and platelets. C. erythrocytes. D. leukocytes. E. plasma.
The sensitivity of the muscle spindle is maintained by ________
A) anulospiral endings B) secondary afferent (group II) fibers C) alpha motor neurons D) a stretch reflex E) gamma motor neurons
Inhaling through the nostrils is preferred over the mouth because
A) there is less resistance to air flow. B) it combines olfaction with respiration. C) it allows better conditioning of the inhaled air. D) bacteria won't be inhaled from the oral cavity. E) it dries out the mouth.