In Cardiac Muscle

question 102

Multiple Choice

In cardiac muscle,

• A) calcium ions are not released from the sarcoplasmic reticulum.
• B) calcium ions do not bind to troponin molecules.
• C) calcium ions play no role in the process of contraction.
• D) about 20 percent of the calcium ion required for contraction comes from outside the cell.
• E) calcium ions play an important role in repolarizing the membrane after the depolarization phase.

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Definitions:

Sulfides

A group of minerals containing sulfur (S) bonded with a metal.

Pyrite

A common, pale bronze to brass yellow, iron sulfide mineral, commonly called “fool’s gold.”

Element S

Refers to Sulfur, a chemical element with the symbol S and atomic number 16, known for its bright yellow crystals.

Rock-forming Minerals

Rock-forming minerals are minerals that make up the majority of Earth's crust and are the basic building blocks of rocks, including quartz, feldspar, and mica among others.