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 has a metropolitan population of 694,960 (U.S. Census Bureau, 2000). Akron is also part of the larger Cleveland-Akron-Elyria Combined Statistical Area, which was the 14th largest in the country with a population of over 2.9 million according to the 2000 Census.