Final answer:
The lingual frenulum is the structure that anchors the tongue to the floor of the mouth, assisting in mobility for eating and speaking.
Step-by-step explanation:
The structure that anchors the tongue to the floor of the mouth is known as the lingual frenulum. This fold of mucous membrane plays a crucial role in the mobility of the tongue and is essential for actions such as speaking, chewing, and swallowing. The tongue has various extrinsic muscles that connect it to surrounding structures like the hyoid bone and mandible, facilitating its movement. There are also instances, such as in the condition ankyloglossia, where an abnormally short or malformed lingual frenulum can impair speech, and surgical intervention may be necessary to correct it.