Final answer:
Sensory structures involved in both sensing the extracellular environment and cell locomotion include cilia and flagella, esthetes, and sensory receptors like free nerve endings and encapsulated endings.
Step-by-step explanation:
The structures that may act as sensory structures, collecting information about the extracellular environment and being implicated in cell locomotion, include:
- Cilia and flagella: These organelles of locomotion contain microtubules and motor proteins, allowing motion along the cell's surface.
- Esthetes: These photosensors extend from the mantle into channels in the upper layer of the shell, and they are unique to chitons.
- Sensory receptors: These specialized cells, such as free nerve endings, encapsulated endings, and receptor cells, interpret specific stimuli (e.g., pain, temperature, light) in various anatomical locations.