1 / 8

Lesson 5 Digestion in the Stomach

Lesson 5 Digestion in the Stomach. Objectives Explore chemical digestion in the stomach Discover the role of pepsin and HCl in digestion Explain why the body needs proteins Bellwork Look at the pictures on page 32 and read the introduction.

horace
Download Presentation

Lesson 5 Digestion in the Stomach

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lesson 5 Digestion in the Stomach • Objectives • Explore chemical digestion in the stomach • Discover the role of pepsin and HCl in digestion • Explain why the body needs proteins • Bellwork • Look at the pictures on page 32 and read the introduction. • Describe the types of digestion that occur in the stomach?

  2. Problem Which substance does the best job of digesting egg white (protien); HCl, pepsin or gastric juice? Hypothesis If egg is soaked in _________then it will digest more completely because ___________. Materials Egg white (tofu), Pepsin, HCl, Gastric juice, 3 test tubes and rack, coffee filter, ruler and graduated cylinder (digital scale?)

  3. You will need to spend some time familiarizing yourself with the preparations on p 46 TM. Refrigerating gastric juice and pepsin. Handling cooked eggs. Teacher demo and control. Steps 7 – 8. Managing test tubes from class to class. Neutralizing HCl and other solutions p 48 TM right-hand column of Safety Tips

  4. Procedure Review safety tips p34 and set up a control using distilled water • Measure 4mL of pepsin, gastric juice and HCl into 3 different test tubes • Use a ruler to measure volume (or use a digital scale to measure mass) of 3 pieces of egg • Place an egg piece into each test tube • Heat test tubes at 37 0C for 45 min and let sit overnight • Empty each test tube onto a coffee filter, rinse and measure again

  5. Data Chemical Digestion in the Stomach Measured using graduated cylinder Measured using digital scale

  6. Conclusion Answer the original question Use data and observations to support your answer Restate hypothesis Next question Homework Read Spies-Into the Blender p38-39 Answer questions on student sheet

  7. Vocabulary Pepsin Ulcer Chyme Pyloric sphincter Gastric (juice) Acid reflux Heartburn

  8. Additional Homework • Read Chance of a Lifetime p37 and answer the questions (Good opportunity to generate “pro” and “con” discussion.) • Use vocabulary words to summarize digestion in the stomach • Describe how a person’s diet would have to change if part of their stomach was removed. • Notebook check • Lab report • Student worksheet • Prep. for lesson 6 p 52 TM • Cut dialysis membrane dry- use warm water to help open • Prepare sugar solution • Bring something with a strong aroma Evaluation

More Related