A Paleontologist Collected Fossils in the Grand Canyon and Recorded

question 8

Multiple Choice

A paleontologist collected fossils in the Grand Canyon and recorded the following data. $\begin{array} { | l | l | } \hline \text { Fossil ID } & \text { Depth from canyon rim } \\\hline \text { PCO3 } & 1,800 \mathrm {~m} \\\hline \text { B8B } & 75 \mathrm {~m} \\\hline \text { 22RD } & 1,757 \mathrm {~m} \\\hline \text { IT-O } & 757 \mathrm {~m} \\\hline \text { GH7 } & 293 \mathrm {~m} \\\hline\end{array}$
The oldest fossil collected is ________ while the youngest fossil collected is ________.

• A) B8B; PCO₃
• B) PCO₃; B8B
• C) 22RD; B8B
• D) IT-O; 22RD

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Definitions:

Synergistically

In cooperation such that the result or effect is greater than the sum of individual effects.

Digestive Tract

A series of hollow organs joined in a long, twisting tube from the mouth to the anus where digestion and nutrient absorption occurs.

Bone

A hard, dense connective tissue that forms the structural elements of the skeleton in vertebrates.

Kidneys

Organs that filter waste products from the blood, regulate blood pressure, and maintain electrolyte balance, among other functions.