Figure 1. Types of movement across membranes. Molecules can diffuse across a. membrane down a concentration gradient without the aid of a protein or the input of. energy. Passive and active transport require membrane transport proteins. Channel. proteins carry out passive transport, but carrier proteins can carry out passive or active. transport.
Akron, Iowa. Akron is a city in Plymouth County, Iowa, United States. The population was 1,486 at the 2010 census.
Akron, MI. Sponsored Topics. Akron is a village in Tuscola County of the U.S. state of Michigan. The population was 461 at the 2000 census. The village is located on the boundary between Akron Township on the north and Fairgrove Township on the south, with the village area approximately evenly split between the two.