Protostomia (from Greek meaning mouth first) are a clade of animals. Together with the deuterostomes and other phyla, they make up the Bilateria, mostly comprising animals with bilateral symmetry and three germ layers.The major distinctions between deuterostomes and protostomes are found in embryonic development.In animals at least as complex as earthworms, the embryo forms a dent on one side, the blastopore, which deepens to become the archenteron, the first phase in the growth of the gut.ogether with the deuterostomes and other phyla, they make up the Bilateria, mostly comprising animals with bilateral symmetry and three germ layers. The major distinctions between deuterostomes and protostomes are found in embryonic development.
A barium enema, or lower gastrointestinal (GI) examination, is an X-ray examination of the large intestine (colon and rectum). The test is used to help diagnose diseases and other problems that affect the large intestine. To make the intestine visible on an X-ray picture, the colon is filled with a contrast material containing barium. This is done by pouring the contrast material through a tube inserted into the anus.
The barium solution will be delivered using an enema â a process in which your doctor pushes a liquid into your rectum through your anus. The barium solution helps to improve the quality of the X-ray images by highlighting certain areas of tissue. The X-ray used in this procedure is known as fluoroscopy. It allows the radiologist to see your internal organs in motion by tracking the flow of the barium solution through your intestinal tract.