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what is true about the structure or function of the plasma membrane?

it is made entirely of integral proteins.

hydrophobic molecules keep the cell from getting too much water.

large molecules often cross the plasma membrane while inside vesicles.

the bilayer structure forms a solid boundary that separates the cell from its environment.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.

i think the answer is composed of atoms