Why are dehydration synthesis reactions important?
Dehydration synthesis is important because it is the process by which many organic polymers are made.
When glucose molecules join together to form amylose (starch) one glucose loses a H and the other glucose loses an OH. The H and OH get together to form water. So when two glucose molecules get together to form a disaccharide, a water molecule is formed and kicked out.
This is why the process is called
Dehydration = lose water
Synthesis = form something new
This process also occurs as amino acids join together to form polypeptides (proteins).