मानव शरीर में निर्जलीकरण (डिहाइड्रेशन) मुख्य रूप से किस पदार्थ की कमी के कारण होता है?

Which digestive hormone inhibits both gastric secretion and motility, stimulates insulin release, and is secreted mainly when fat is present in the duodenum?

The repeated sequence of gradual onset of apnoea followed by gradual restoration of respiration is called ________.