Which statement is true?
a. the autonomic nervous system has no effect on the heart
b. the AV node can generate electrical impulses just as quickly as the SA node
c. If the pacemaker of the heart fails, then heart will stop beating
d. if the pacemaker of the heart stops, the AV node will take over
Answer: d. if the pacemaker of the heart stops, the AV node will take over
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A pyrogen induces the development of ____________________
Fill in the blank(s) with correct word
When a hormone binds to a membrane–bound receptor and activates G proteins,
A. ion channels could be opened. B. IP3 may be activated. C. cyclic AMP production may be increased. D. DAG may be activated. E. All of the choices may occur from activated G proteins.
The torque of a muscle (rotary component) is greatest in what position?
A. when the moment arm is longest B. when the muscle insertion is 90° to the bone C. both A and B D. position does not affect torque
A cell in the pancreas that secretes an enzyme to hydrolyzes lipids would be expected to have
a. a larger-than-normal nucleus b. an extensive rough ER c. a greater-than-normal number of free ribsomes d. an extensive smooth ER e. a and d