What is osmosis? What is active transport?
Osmosis is the movement of water from high to low concentration across a membrane. Active transport is the transfer of substances across membranes by a cell against a concentration gradient. 26. Describe four adaptations used by estuarine organisms to deal with living in the mud. Most estuarine organisms either burrow or live in permanent tubes beneath the sediment surface. Clams and other bivalves extend their siphons to the surface to get water for food and oxygen. Some organisms have special hemoglobins so that they can survive in oxygen-poor sediments. 27. List the six types of estuarine communities. The six distinctive communities associated with estuaries are open water, mudflats, salt marshes, mangroves, sea grasses, and oyster beds. 28. Describe open water communities in estuaries. The open water community is the plankton, fishes, and other organisms that come in to and leave the estuary with the tides. The plankton are mostly marine species. Estuaries are nurseries, where many
