Kayla and Layla Are Twins Who Were Separated at Birth

question 48

Multiple Choice

Kayla and Layla are twins who were separated at birth. A researcher interested in studying heredity tracks them down and speaks to their different families about the benefits that can be achieved by studying the two young girls. The girls and their different sets of parents agree to participate, and studies begin to assess various areas of the girls' lives. In order for this type of twin study to be most effective, what kind of twins should Kayla and Layla be?

• A)conjoined
• B)monozygotic
• C)amorphous
• D)dizygotic

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Definitions:

Island Arc

A curved chain of volcanic islands located at a tectonic plate boundary, formed by the subduction of an oceanic plate beneath another.

Gabbro

A coarse-grained igneous rock that forms from the slow cooling of magma beneath the Earth's surface, composed mainly of plagioclase feldspar and pyroxene.

Welded Rhyolite

Is a type of volcanic rock that has been superheated and compacted under extreme conditions, resulting in a dense, hard rock.

Calderas

Large, usually circular depressions in the ground caused by volcanic activity, specifically the collapse of a magma chamber after a volcanic eruption.