Structure number 2 is the_ and most like the_
system
in the human body because it_.

Structure number 2 is the nucleus  and most like the nervous  system  in the human body because it controls and regulates the cell much like the nervous system does

Explanation:

not sure but try c two haploid cells

explanation:

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.