In Which of the Following Forms Does Ca²⁺ Exhibit Profound

question 154

Multiple Choice

In which of the following forms does Ca²⁺ exhibit profound effects on such things as neuromuscular excitability?

• A) free, unbound diffusible Ca²⁺
• B) intracellular Ca²⁺
• C) calcium phosphate crystals impregnated in the organic matrix of bone
• D) calcium bound to plasma proteins

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Definitions:

White Matter

Brain and spinal cord tissue consisting mainly of myelinated nerve fibers that transmit signals.

Gray Matter

Regions of the brain and spinal cord that are primarily made up of neuronal cell bodies, dendrites, and unmyelinated axons, involved in muscle control and sensory perception.

Ventral Motor Root

The part of a spinal nerve that carries motor signals from the spinal cord to the body, controlling muscle movements.

Filum Terminale

A slender fibrous tissue thread that extends from the apex of the conus medullaris to anchor the spinal cord in the lower vertebral canal.