Is the stingray autotrophic or heterotrophic?

Explain why phospholipid molecules form a bilayer. (3 marks)

Based on anatomical similarities, to which modern animal is dr. digger’s creature most closely related?

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).