Name two common characteristics crayfish share with annelids

Crayfish belongs to the class arthopoda.  

Thus in this way the common characteristics of kingdom annelids and arthopda are –  

1 The body of both the annelids and arthopoda is segmented. Annelids have several segments in their body with each segment having all essential body systems for life such as respiratory system , nervous system etc. while the crayfish (arthopods) has two body parts a)  cephalothorax having  head and upper body b) segmented abdomen.  

2. They both  live in water  

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.