Answer:
The order of events would be:
4.Threshold stimulus, Na+ channels open. This is the first event
5.Na+ influx, Depolarization. Second event
2.Na+ channels close, K+ channels open. This is the third event
1.K+ efflux, Repolarization. Fourth event
3.Hyperpolarization, K+ channels close
Explanation:
In resting state, the membrane is negative inside, and K+ concentration is higher than outside. Na+ concentration is higher outside instead.
Sodium influx is responsible for membrane depolarization. It's the event to produce the action potential. When sodium channels are closing, potassium channels open and K+ go outside until repolarization occurs. But now we have both ions in different sides of the membrane, and this can't be stimulated again to produce other action potential. The membrane will remain refractory to respond to the adequate stimulus until ions migrate to their original sites. This is Na+ outside, and K+ inside. This is responsibility of the Na+/ K+ pump, that uses ATP to pump Na+ out, and K+ in. Once both ions had been relocated in the membrane, this is ready to receive a correct stimulus to produce a new action potential.
For example, if the acceleration is zero, then the velocity-time graph is a horizontal line (i.e., the slope is zero). If the acceleration is positive, then the line is an upward sloping line (i.e., the slope is positive). ... If the acceleration is great, then the line slopes up steeply (i.e., the slope is great).
<h3>option A is the correct one </h3>
hope this helps you out
Answer: E) Emesis from irritation of the stomach.
Explanation:
The gastroesophageal reflux disease, is a disorder of digestive system which affects the esophageal sphincter. Many people suffer from heartburn or acid indigestion caused by this disease. The overweight and pregnant individuals suffer from this disease.
In normal process of digestion, the esophageal sphincter opens to allow food to pass into the stomach and close so as to prevent food and acidic juices from stomach from flowing back to the esophagus. This disease makes the esophagus sphincter weak , that causes the stomach's contents to move up into the esophagus, this may result in vomiting. The acids in the stomach may cause ulcers.
