Question Detail
Question
In ciliates like Paramecium, the permanent funnel-shaped depression that directs food into a short 'cell gullet' is called the:
Correct Answer
Option D is the correct answer.
Detailed Explanation
The document details, 'In ciliates such as Paramecium, food is directed by ciliary action into a permanent funnel-shaped depression called the cytostome ('cell mouth'), which leads into a short cytopharynx ('cell gullet'); food vacuoles pinch off at the inner end of the cytopharynx and circulate within the endoplasm as digestion proceeds.'
Hint
Look for the specific 'mouth' structure mentioned for ciliates.