All plants have a 2 part life cycle that includes a haploid phase and a diploid phase. we call this life cycle question 2 options:

The answer is; alternation of generation.

The haploid phase is represented by the gametophyte while the diploid phase is represented by the sporophyte. Lower plants (such as liverworts and mosses) have a dominant haploid phase while higher plants (such as angiosperms and gymnosperms) have a dominant diploid phase.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products