The Sponges Date Back to

question 51

Multiple Choice

The sponges date back to

• A)the Devonian period or "age of fishes."
• B)the early time of anaerobic prokaryotes.
• C)the Cambrian period and probably earlier.
• D)the time of the first prokaryotes but the sponges left no fossil evidence for lack of hard parts.Ancestral members of the phylum Porifera arose at least by the early Cambrian period and probably into Precambrian times.Later evolution resulted in diversification into the classes present today.

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Definitions:

Six-figure Accuracy

A level of precision where calculations or measurements are correct to six digits.

Cube Root

The number that produces a given number when cubed. It is the value that, when multiplied by itself three times, gives the original number.

Six-figure Accuracy

Refers to a level of precision in numerical calculations or measurements that includes six digits.

Pair Of Equations

Two equations that are solved together to find a common solution.