The defecation reflex involves two postive feedback loops. these loops are the stretch receptors in the rectal walls and the sacral parasympathetic system. Defecation reflex empties the rectum by peristaltic movements push fecal matter from the sigmoid colon into the rectum. Then this distension of the rectal walls stimulates stretch receptors which results in defecation.
D. Visible light . Is the correct answer I hope this helps:)
Some individuals are more likely to survive and reproduce than others because they are fit and easily adapting. This idea is called 'survival of the fittest'.
Answer:
The structure of their noses.
Explanation:
Catarrhines are distinguished from platyrrhines by several traits but the main distinctive feature between them, is the structure of their noses. This forms the basis of their names.
Platyrrhines are characterized by laterally-placed, rounded nostrils or flat-nosed while catarrhines have narrow, downward-facing nostrils or hooked-nosed.
Another distinguishing feature include their dental formulation which is 2.1.2.3 in catarrhines and 2.1.3.3 in platyrrhines.
The skull structure of catarrhines have frontal bone which make contact with the sphenoid bone unlike the platyrrhines.
Generally, catarrhines are much bigger in size than platyrrhines.