Approximately 3 hours following a well-balanced meal, blood levels of which of the following are elevated?
1) Fatty acids
2) Glucagon
3) Glycerol
4) Chylomicrons
π Explanation:
Following digestion, the products of digestion enter the bloodstream.
These include glucose, amino acids, triacylglycerides packaged into chylomicrons from the intestine, and very low density lipoproteins from the liver.
The hormone of anabolism, insulin, is also elevated because of the signaling of the glucose and amino acids in the blood, which allows release of insulin from the β-cells of the pancreas. Insulin aids the movement of glucose and amino acids into cells. In contrast, all the hormones and energy sources associated with catabolism are decreased in the blood during this time. Long-chain fatty acids and glycerol released by lipolysis from adipocytes are not elevated. Glucagon and epinephrine are not released. The only time glucose levels rise significantly above approximately 80 mM is following a well-balanced meal when glucose is obtained from the diet. The concentration of glucose reaches a peak 30 to 45 minutes after a meal and returns to normal within 2 hours after eating. This response of blood glucose after eating (mimicked by giving 50 g of oral glucose) is the basis for the glucose tolerance test. In the event of insulin deficiency (diabetes mellitus), the peak glucose concentration is abnormally high and its return to normal is delayed.
MCQ