Question

You have just eaten a lunch that included a hamburger on a whole-wheat bun, a glass of low-fat milk, and a bunch of grapes. Trace the digestion and final use of each of the macronutrients present in your lunch. What are (a) the enzymes, locations, and breakdown products formed in the complete digestion of these foods; (b) the routes taken by the breakdown products after absorption; and (c) one possible body use?

Answer 1

a.Answer

The body produces digestive enzymes for protein, fat, and carbohydrates which help it digest mixed meals. Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma

Hamburger consists of – protein, starch (carbohydrates) and fat

Milk – Milk protein and minerals & vitamins

Grapes - Fiber

It starts breaking down and digesting by the saliva in the mouth which has an enzyme called Amylase

It moves into stomach the hydrochloric acid starts digesting the protein; here pepsin enzyme will play a role. In humans milk protein digesting enzyme in stomach is pepsin

Then thick juice of food moves into duodenum where bile juice and pancreatic juice will mix and 95% of the nutrients will get absorbed in the small intestine.

Water and minerals are reabsorbed back into the blood in the colon Waste material is eliminated from the rectum during defecation

**Grapes are high in insoluble fiber, meaning that they remain intact as they move through the digestive tract

b.Answer

Carbohydrates, fats and proteins all pass through the digestive system at a different pace, are broken down into unique components and are absorbed into the body for use as fuel or to repair and build muscles, bones and organs.

Carbohydrates: absorbed through the small intestine walls into the bloodstream and used by the body as fuel or sent for storage in the liver for use at a later time

Proteins: A number of enzymes, including substances from the pancreas, then break down protein into its component amino acids in the small intestine. Amino acids are absorbed through the wall of the small intestine into the bloodstream and distributed throughout the body to repair injuries and replace dying cells.

Fats: absorbed through the intestinal walls into the bloodstream, where they accumulate in the chest veins and are then carried to fat-deposit areas throughout the body to be stored and used for fuel when necessary.

Vitamins - A, D, E and K are absorbed through the intestinal walls and stored in the liver and adipose tissue, or body fat, for use when needed.

c. Answer

Protein from the burger and milk product turns into amino acid which will replace dying cells.

Grapes reduces constipation problems