Highly specific for ethanolamine phosphorylation. May be a rate-controlling step in phosphatidylethanolamine biosynthesis. ATP + ethanolamine = ADP + H(+) + phosphoethanolamine Phospholipid metabolism; phosphatidylethanolamine biosynthesis; phosphatidylethanolamine from ethanolamine: step 1/3. Expressed in kidney, liver, placenta, heart, leukocyte, ovary and testis. Belongs to the choline/ethanolamine kinase family.