Which of the following best describes the niche of a sunflower plant

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

The seed coat's most important function is to provide a) a nonstressful environment for the megasporangium. b) the means for dispersal. c) dormancy. d) a nutrient supply for the embryo. e) desiccation resistance.

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.