Genomic Analysis of the Sea Urchin Led to the Discovery

question 28

Multiple Choice

Genomic analysis of the sea urchin led to the discovery that there are no genes coding for gap-junction proteins or for adrenaline. Functionally, this suggests that

• A) there are no gap junctions in sea urchins.
• B) there is no cellular communication system in sea urchins.
• C) sea urchins are not related to vertebrates.
• D) the cellular communication system of sea urchins is unusual.

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Definitions:

Early Crystallization

Early crystallization refers to the initial phase of crystal formation from a cooling magma or solution, influencing the texture and composition of igneous rocks.

MgO Content

The percentage of Magnesium Oxide present in a geological sample, important in determining rock composition and origins.

SiO Content

Refers to the concentration of Silicon Dioxide, a common compound found in the Earth's crust, often significant in determining the composition of rocks and soils.

Mafic Minerals

Dark-colored minerals that are rich in magnesium and iron, typically found in basalt and other mafic rocks.