Which of the Following Statements Concerning the Differences Between Action

question 141

Multiple Choice

Which of the following statements concerning the differences between action potentials in skeletal muscle cells and in ventricular cardiac muscle cells is TRUE?

• A)Like skeletal muscle cells,ventricular cardiac muscle cells have a resting membrane potential closer to the sodium equilibrium potential than to the potassium equilibrium potential.
• B)Unlike skeletal muscle cells,the initial depolarization of ventricular cells is mainly due to calcium influx,not sodium influx.
• C)After sodium influx through voltage-gated channels occurs in ventricular cells,prolonged influx of calcium from the extracellular fluid occurs.No such calcium influx occurs in skeletal muscle cells.
• D)Action potentials in skeletal muscle cells are longer in duration than action potentials in cardiac muscle cells.
• E)The efflux of K⁺ repolarizes skeletal muscle cells after an action potential,while repolarization in cardiac muscle cells is due to the efflux of Ca²⁺. 

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Definitions:

Coxal Bone

Another term for the hip bone, comprising the ilium, ischium, and pubis, that forms part of the pelvis.

Pelvic Girdle

The ring of bones in the lower torso, comprised of the two hip bones, sacrum, and coccyx, providing support for the human body's weight.

Axial Skeleton

The axial skeleton is the part of the skeleton that consists of the bones of the head and trunk of a vertebrate, including the skull, spine, sternum, and ribs.

Cancellous Bone

a type of bone that is less dense, more porous, and found at the ends of long bones and in the inner layers of most bones, important for metabolic processes.