When proteins help transport molecules in and out of the cell, it is called . passive diffusion
facilitated diffusion
active transport
endocytosis and exocytosis

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

Match the pollutants. 1. a chlorofluorocarbon smoke 2. a biodegradable organophosphate insecticide freon 3. particle pollution paint 4. hazardous waste monoxide 5. carbon is completely burned malathion 6. carbon is incompletely burned dioxide

Black fur(b) in guinea pigs is dominant over white fur(b). find the probability of a homozygous offspring in a cross: bb x bb. a. 0% b. 25% c. 50% d. 75% e. 100%