1. Describe a positive result for each of the tests that you performed in the lab.
When we rubbed the food against the paper the and left it for around ten minutes. When we saw the paper after the ten minutes we noticed that there were transparent spots which meant that it was a positive result for lipids.
When we added iodine to the food the food would turn to black if it contained starch.
After adding Benedict's solution if it turned yellow it was positive and it meant that it had simple sugars.
2. Starch molecules are large carbohydrate polymers. Find and post an image of the molecular structure of starch. What are the building blocks that starch molecules are made of?
The building blocks are glucose molecules and 2 of them are known as maltose but when single known as an monomers.
3. Thomas and Josh had interesting results to their simple sugar test - if you are following either of their blogs, look at their picture of their test tubes after they took them out of the hot water bath.
After 2 minutes, only 2 of the test tubes were yellow/orange, and the rest remained blue. They took the two positive test tubes out of the hot water bath and left the others in the hot water bath for 2 more minutes. At the end of the two extra minutes all the test tubes indicated a positive result. Based on your knowledge of carbohydrate molecules, why do you think they got these results?
The reason why they had to leave the other test tube in the hot water was because those food items, starch molecules were probably bigger so it took a longer time for the heat to break the starch chain into glucose molecules. So after the two more minute the hot temperature was able to break the starch chain and it became a positive for glucose because the chain is made of little glucose molecules. And when it is broken down the starch polymer becomes into a glucose monomer.
4. Making connections - Describe the passage of one of your food items through the digestive system, starting with the mouth & ending at the anus. Include the specific enzymes, accessory organ secretions & internal conditions the food/chyme would pass through from start to finish.
Start off with chewing on your food where your salivary glands shoot salivary amylase which breaks down your food, the amylase breaks it into maltose. And then your tough send your food bolus into the back of your throat. And then the food bolus goes down goes down your esophagus by peristalsis, down to the cardiac sphincter. the sphincter opens and the bolus enters the stomach where there is gastric juice which makes the bolus into chyme. The chyme leaves the stomach from the pyloric sphincter and enters the duodenum, in here there is enzymes beings put into the chyme, they come from the pancreas. Then the chyme goes through the small intestine where nutrients is absorbed from there. Then the large intestine where water is absorbed. Then into the rectum where they become poop and is released out of the anus.
