In your biology lab, The distinguishing animal trait "A," that separates the body forms of the eumetazoa and then parazoa use a stereoscopic microscope to observe a living animal that uses only one opening to both take in its food and eject its waste products. What is the body arrangement of this animal

The options:

A. incomplete digestive tract

B. gastrovascular cavity

C. complete digestive tract

D. complete digestive tract and a gastrovascular cavity

E. incomplete digestive tract and a gastrovascular cavity

The CORRECT ANSWER IS E.

E. incomplete digestive tract and a gastrovascular cavity

Explanation:

Phylum Cnidaria; Cnidarians are diploblastic with two embryonic germ layers -the ectoderm and the endoderm) with well structured tissue, performs extracellular digestion, and use cnidocytes for defence and to catch prey.

Cnidarians have two unique morphological body plans which are referred to as polyp, its sessile in adults, and medusa are mobile; some species has both body structures in their lifecycle.

It undergo extracellular digestion, where enzymes dissolve the food substances as its cells lining the gastrovascular cavity take in the nutrients.

Cnidarians are known to have a body arrangement of incomplete digestive system with just one opening; the gastrovascular cavity that functions as both a mouth and an anus.

The cnidarians undergo extracellular digestion, the food is moved to the gastrovascular cavity, enzymes are present in the cavity, with the cells lining the cavity taken in nutrients. The gastrovascular cavity possess a singular opening that acts as a mouth and an anus; this is referred to as an incomplete digestive system.

from my research i have to the conclusion that decomposers, such as fungi, bacteria and invertebrates, play a critical role in nutrient cycling and without them the earth's ecosystem may not support life as we know it. elements such as carbon, nitrogen and phosphorus exist in limited amounts on earth, although huge amounts of carbon are being released into the atmosphere from underground sources now by humans. it is still extremely important that other nutrients be retained by the process of re-use. decomposers are organisms that are able to chemically break down dead material and make these elements available for use by other organisms. without this breakdown of dead material, dead bodies would pile up. so decomposers also play a role in clean up also. without them, life might not continue as we know it and dead material would overwhelm the earth.