(3) increased fatigue is your answer.
Answer: Membrane proteins act as receptors to molecules like hormones.
Explanation:
Membrane proteins are proteins that are closely associated with a cell membrane. On the cell membrane, they could act as receptors to molecules like hormones that need to be transported across the hydrophobic lipid bilayer.
A good example of membrane proteins is sodium channel, that acts as receptor to neurotransmitters.
Answer: Coal is primarily used as fuel to generate electric power in the United States. In coal-fired power plants, bituminous coal, subbituminous coal, or lignite is burned. The heat produced by the combustion of the coal is used to convert water into high-pressure steam, which drives a turbine, which produces electricity.
Explanation: