A reaction that absorbs energy from the environment a reaction that requires an activation energy a reaction that releases energy into the environment a reaction that does not involve a change in energy

25) a student takes four samples of a white crystalline solid and places each in a well plate. on top of each sample, she carefully places 20 drops of clear mystery liquids a, b, c and d. her results for each well are: liquid a: the solid dissolves quickly. liquid b: the solid appears unchanged. liquid c: a brownish colored liquid is produced. liquid d: fizzing occurs and the well becomes warmer. in which well does a physical change occur?

Place the steps tor the formation of the enzyme pepsinogen in correct order

Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria