Answer:
C: Lowering activation energy
Explanation:
A catalyst speeds up a chemical reaction, without being consumed by the reaction. It increases the reaction rate by lowering the activation energy for a reaction.
One unique feature of stratosphere is that it contains a layer of ozone gas, which protect us from the sun's rays.
Haemoglobin takes oxygen and gives it to the cells thus hemoglobin is free to carry more oxygen.
The 1st one is plasma membrane because it is the outside
the 2nd one is the cytoplasm because it is the middle part
the 3rd one is the nucleus because it is the center
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