Context and question: Different phases of digestion take place including: the cephalic phase , gastric phase, and intestinal phase. The cephalic phase occurs at the sight, thought and smell of food, which stimulate the cerebral cortex. Taste and smell stimuli are sent to the hypothalamus and medulla oblongata. After this it is routed through the vagus nerve and release of acetylcholine. Gastric secretion at this phase rises to 40% of maximum rate. Acidity in the stomach is not buffered by food at this point and thus acts to inhibit parietal (secretes acid) and G cell (secretes gastrin) activity via D cell secretion of somatostatin. The gastric phase takes 3 to 4 hours. It is stimulated by distension of the stomach, presence of food in stomach and decrease in pH. Distention activates long and myenteric reflexes. This activates the release of acetylcholine, which stimulates the release of more gastric juices. As protein enters the stomach, it binds to hydrogen ions, which raises the pH of the stomach. Inhibition of gastrin and gastric acid secretion is lifted. This triggers G cells to release gastrin, which in turn stimulates parietal cells to secrete gastric acid. Gastric acid is about 0.5% hydrochloric acid (HCl), which lowers the pH to the desired pH of 1-3. Acid release is also triggered by acetylcholine and histamine. The intestinal phase has two parts, the excitatory and the inhibitory. Partially digested food fills the duodenum. This triggers intestinal gastrin to be released. Enterogastric reflex inhibits vagal nuclei, activating sympathetic fibers causing the pyloric sphincter to tighten to prevent more food from entering, and inhibits local reflexes.
Where does the cephalic phase occur?
Answer: at the sight, thought and smell of food, which stimulate the cerebral cortex
Context and question: The Republic of Liberia, beginning as a settlement of the American Colonization Society (ACS), declared its independence on July 26, 1847. The United States did not recognize Liberia's independence until during the American Civil War on February 5, 1862. Between January 7, 1822 and the American Civil War, more than 15,000 freed and free-born Black Americans from United States and 3,198 Afro-Caribbeans relocated to the settlement. The Black American settlers carried their culture with them to Liberia. The Liberian constitution and flag were modeled after the United States. In January 3, 1848 Joseph Jenkins Roberts, a wealthy free-born Black American from Virginia who settled in Liberia, was elected as Liberia's first president after the people proclaimed independence.
What country did Liberia gain independence from?
Answer: unanswerable
Context and question: Wood, in the strict sense, is yielded by trees, which increase in diameter by the formation, between the existing wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots. This process is known as secondary growth; it is the result of cell division in the vascular cambium, a lateral meristem, and subsequent expansion of the new cells. Where there are clear seasons, growth can occur in a discrete annual or seasonal pattern, leading to growth rings; these can usually be most clearly seen on the end of a log, but are also visible on the other surfaces. If these seasons are annual these growth rings are referred to as annual rings. Where there is no seasonal difference growth rings are likely to be indistinct or absent.
What is the process of trees growing out to get bigger around called?
Answer:
secondary growth