Answer: the correct answer is d. all of the above must happen for defecation to occur.
Explanation:
In response to the distention of the rectal wall, the receptors send sensory nerve impulses to the sacral spinal cord. Motor impulses from the cord travel along parasympathetic nerves back to the descending colon, sigmoid colon, rectum, and anus. The resulting contraction of the longitudinal rectal muscles shortens the rectum, thereby increasing the pressure within it. This then opens the internal sphincter.
The sun is a very big star that was created by many minerals and every star and put together
Single or multi-celled structure, membrane-bound organelles, cell(s) larger than prokaryotes
The answer is true for this question