MDCAT Biology MCQ #439

A biochemistry student compares the molecular structures of Chlorophyll a and Chlorophyll b. Which structural feature uniquely identifies Chlorophyll a?

MDCAT Biology MCQ #439

  1. Question 1

    Q1. A biochemistry student compares the molecular structures of Chlorophyll a and Chlorophyll b. Which structural feature uniquely identifies Chlorophyll a?

    • A) Presence of a magnesium ion in the porphyrin ring
    • B) The presence of a methyl group instead of an aldehyde group
    • C) The length of the hydrophobic phytol tail
    • D) The ability to absorb light in the blue-violet spectrum

    Answer: The presence of a methyl group instead of an aldehyde group

    Explanation: Chlorophyll a contains a methyl group at the third carbon, whereas chlorophyll b possesses an aldehyde group in that specific position.