During Contraction of Heart Muscle Cells ________

question 41

Multiple Choice

During contraction of heart muscle cells ________.

• A) the action potential is initiated by voltage-gated slow calcium channels
• B) some calcium enters the cell from the extracellular space and triggers the release of larger amounts of calcium from intracellular stores
• C) the action potential is prevented from spreading from cell to cell by gap junctions
• D) calcium is prevented from entering cardiac fibers that have been stimulated

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Definitions:

X-Linked Recessive Disorders

Genetic conditions caused by mutations in genes on the X chromosome, usually manifesting in males who have only one X chromosome, and are less affected in females who have two X chromosomes.

Waddling Gait

A pattern of walking characterized by a side-to-side motion, often seen in conditions affecting the hip or leg muscles.

Duchenne Muscular Dystrophy

Genetic disorder that is characterized by a wasting of muscle tissue; displays an X-linked recessive pattern of inheritance.

Sex-Linked Diseases

Disorders that are determined by genes located on sex chromosomes, often affecting one sex more than the other.