Which best illustrates a resultof natural selection?

Which skill, if it cannot be performed by a 3-year-old child, should alert the nurse that the child may be developmentally delayed?

Ectocarpene is a volatile, sperm cell-attracting material released by the eggs of the seaweed ectocarpus siliculosus. its constitution is all the double bonds are cis, and the absolute configuration of the chirality center is s. draw a stereochemically accurate representation of ectocarpene.

Which image shows labeled organelles that are present only in plant cells?