Which is a form of active transport? proteins push molecules through the cell membrane. proteins create openings on another side of the cell membrane. proteins open up channels in the cell membrane. proteins enter and exit the cell freely.

Plz ! cattle ranchers and dairy farmers rarely allow all of their animals to reproduce instead they practice selective breeding and only encourage the reproduction of animals with specific features. which of the following cows would a dairy farm most likely choose to reproduce? a. a cow that makes a lot of milk. b. a cow that can run quickly. c. a cow with a think, soft fur. d. a cow with large, strong hooves.

Why are common names a problem for scientist?

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods.c. it shows that these organisms share the same habitat.d. it provides evidence that these organisms suffered a genetic mutation.