Final answer:
The inner space of the GI tract is known as the lumen, lined with mucosal cells including epithelial tissue that facilitates secretion and absorption.
Explanation:
The inner space of the GI tract lined with mucosal cells is referred to as the: lumen.
The mucosa, which is the innermost layer surrounding the lumen, consists mainly of epithelial tissue capable of secreting and absorbing substances.
For example, the epithelium within the mucosa can secrete digestive enzymes and mucus while also absorbing nutrients and water.
Learn more about GI tract anatomy here:
https://brainly.com/question/39059930
