The ¹³C/¹²C Isotopic Ratio of Geological Rocks of Different Ages

question 23

Multiple Choice

The ¹³C/¹²C isotopic ratio of geological rocks of different ages has been used to examine whether previous biological activity occurred because compounds of biological origin

• A) do NOT contain ¹³C.
• B) have a higher proportion of ¹³C that compounds of geological origin.
• C) have a lower proportion of ¹³C that compounds of geological origin.
• D) are not well preserved in geological samples.

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Definitions:

Gastric Acid Production

The process by which the stomach produces hydrochloric acid necessary for digestion.

Cleft Lip and Palate

Congenital deformities affecting the upper lip and roof of the mouth, respectively, that can impair speech, eating, and hearing.

Gastrostomy Feedings

Nutritional support provided through a tube placed directly into the stomach for those who cannot eat by mouth.

Sucking Needs

The innate need for sucking movements seen in infants, critical for feeding and offers comfort.