A ________ Is an Open Cavity in a Volcanic Rock

question 161

Multiple Choice

A ________ is an open cavity in a volcanic rock that was filled by a gas bubble when the lava was still mainly liquid.

• A)porphyrocryst
• B)vesicle
• C)phenocryst
• D)xenocryst

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Definitions:

Vertebra

One of the individual bones that make up the vertebral column (spine), providing structural support and protecting the spinal cord.

Pelvic Girdle

Site of attachment of the lower limb to the trunk; ring of bone formed by the sacrum and the coxal bones.

Appendicular

Pertaining to the limbs or extremities of the body, including the bones of the arms, legs, and the girdles (shoulder and pelvic) that attach them to the axial skeleton.

Intervertebral Disk

A layer of cartilage located between adjacent vertebrae in the spine, serving as a shock absorber and allowing for mobility of the spine.