"Why are yawns contagious? We asked a scientist" by Teresa Carey Why do we yawn? There is no scientific consensus on why we yawn. One theory argues that when humans are tired, we stop taking deep breaths, which causes a build-up of carbon dioxide in the body, said Douglas Parham, a speech scientist at Wichita State University. A yawn might be a special kind of respiration, Parham said. It builds up oxygen quickly, while expelling carbon dioxide, even more than a deep breath. Excess carbon dioxide and other chemical changes, such as a drop in oxygen or increase in a compound called adenosine, could also act as “yawn gates,” said James Giordano, a neuroethicist and neuroscientist at Georgetown University. These chemicals send out a signal that triggers a yawn. By yawning, we compress the muscles of the face, driving oxygen-enriched blood to the brain, Giordano said. Other proposals state the purpose of yawning is to cool the brain, or to stretch internal organs like tissues and lungs, helping the body to liven up. © NewsHour Productions LLC. All Rights Reserved. Question Use the passage from “Why are yawns contagious? We asked a scientist.” to answer the question. Effect: We yawn. Cause: to quickly expel carbon dioxide Cause: to drive oxygen-enriched blood to the brain Cause: to stretch internal organs Cause: ? Cause: ? Based on the information in the passage, which cause completes the graphic organizer? Select the two correct answers. (1 point) Responses to increase adenosine levels to increase adenosine levels to increase the frequency of deep breaths to increase the frequency of deep breaths to compress facial muscles to compress facial muscles to build up oxygen to build up oxygen to cool the brain to cool the brain
1 answer
Based on the information in the passage, the two correct answers that complete the graphic organizer are:
These options align with the theories and explanations provided in the passage regarding the causes of yawning.
