Answer True or false to all options
![Noradrenaline treatment...
increases the duration of the depolarization
[ Choose ]
phase of pacemaker cell action potentials
decreases the pulse rate
[ Choose ]
increases UCP1 activity
[ Choose ]
increases UCP1 gene expression
[ Choose ]
increases the rate of potassium export in
[ Choose ]
pacemaker cells
>
>
>
>
>](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fa6c5565a-787b-43d3-b23e-780453faf6da%2F829588d4-01ca-4693-bec2-1e60d4d7ed1a%2Fhzk8s3i_processed.png&w=3840&q=75)
The heart is made up of cardiac muscle. It contains network of specialized cardiac muscle fibers called autorhythmic fibers because they are self-excitable. They generally generate action potentials that trigger heart contractions. Cardiac action potentials normally begin in the sinoatrial node (SA node), which act as the heart's pacemaker, initiating cardiac action potentials that causes contraction of the heart. Membrane potential arise due to change of ion concentration inside and outside of the cell. As influx of Na+ increase, by a stimulus, the membrane is depolarized, then sodium gated ion channels are inactivated and the membrane reaches a positive potential due to influx of Ca2+ ions, then the Ca2+ channels close and K+ channels open and the membrane repolarize by the movement of K+ out of the cell.
Step by step
Solved in 5 steps
