What differentiates passive transport from active transport? A. Proteins have a role in passive transport.

B. Molecules move down a concentration gradient during passive transport.

C. Passive transport involves molecules moving across the cell membrane.

D. ATP is needed for passive transport to occur.

How does the molecular clock work? a. it analyzes the brain functionality of two different species.b. it examines and compares the physical characteristics of two different species.c. it illustrates relationships between two different species.d. it compares the number of mutations that exist in the dna of two different species.

How are gross production and net production different? a. net production is always greater than gross production. b. net production is always less than gross production. only animals have net production. d. only plants have net production. select the best answer from the choices provided

Babies with very low or very high birth weight are less likely to survive. observe a graph of the data.