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 correct answer is true. Both intramembranous ossification and endochondral ossification originates from a primary ossification center. The primary ossification center, as the name implies, is the focus where the bone tissue starts ossifying. Primary ossification centers are usually found in the diaphysis of long bones or in the body of irregular bones.
The difference between cytoplasm and cellcytoplasm is jelly like fluid part of the protoplasm
According to my knowledge there are many. Ribosomes, Centrioles, ER. <span>cellular structure is NOT surrounded by at least one membrane.</span>