Answer:
Epidermal cells secrete the waxy hydrophobic substance cutin that polymerizes on the surface, forming a barrier to water evaporation. Epidermal cells are transparent because their plastids remain small and undifferentiated; hence light readily penetrates through to the photosynthetic tissues beneath the epidermis.
Explanation:
All amino acids are structurally the same, in that they contain a central carbon atom, an amine group, a lone hydrogen at. Our DNA is contained in our chromosomes. The thing that is different about each of the 20 amino acids is the make-up of the R group
I believe it's sexual reproduction in sea stars if that's the question.
<span />
