Select the feature that best describes cell membranes helps cell move through fluid habitats
b.
physically separates an external environment from an internal one
c.
contains ribosomes
d.
involved in binding to signaling molecules

Ascientist is designing an investigation to study the impact of invasive bird populations on local, native bird populations at backyard bird feeders. what population is most likely to be a control group for the investigation? amount of food number of bird feeders invasive bird populations local backyard birdfeeders without food