What is the relevance of studying stem parts?

Question

What is the relevance of studying stem parts?

Answer 1

Modified stems can be locations of starch storage like tubers or bulbs. Stems can be the means of clonal reproduction with stolons or rhizomes.

http://www.backyardnature.net/stemtype.h...

Stems may have lenticels or pores for gas exchange through the cuticle or bark. In dormant plants stems with perennial woody structure maintain a basal metabolism that can be monitored.

Stems are the sites of water transport in different types of vascular structures. This structure confirms different strengths to the wood. We use this difference to classify monocots and dicots. Dicots have lateral meristem, between bark and pith, to add girth while Monocots have intercalary meristems located at the base of each internode.

http://academic.kellogg.cc.mi.us/herbran...

In the case of cacti the stem is modified to provide photosynthesis so leaves have become microscopic to prevent water loss from the greater surface area leaves provide. The evolutionary conversion of leaves to miniatures or to spines in cacti.

http://www.sbs.utexas.edu/mauseth/Resear...