Human Digestive System

Transcription

1 Human Digestive System Extension Independent Study Activity Article 1 The Human Microbiome, p2-p5 Article 2 Stomach Ulcers, p6-p12 Question Booklet Instructions: Read the above two articles and answer the questions in this booklet. All resources can be accessed at: Completion Date:

2 Anticipation Guide Directions: Before you read the article The Human Microbiome - in the first column, write A or D indicating your agreement or disagreement with each statement. As you read, compare your opinions with the information from the article. In the space under each statement, cite information form the article that supports or refutes your original ideas. Me Text Statement 1. Microbes inhabit all areas of the human body. 2. There are ten times more bacteria than there are cells that make up the human body. 3. Humans have a metagenome. 4. Commensal and mutualistic have the same meaning. 5. Bacteria form biofilms 6. Competition between bacteria can help prevent disease % of faecal matter is made up of bacteria. 8. Alteration of the microbiome can lead to obesity. 9. The human microbiome is identical in all human. 2

3 Graphic Organiser Directions: As you read, complete the graphic organiser below on the microbiome. What are the functions of the human Microbiome? What is metagenomics? Where are sterile locations in the human body? What are the species of bacteria in the human microbiome? Calculation Calculate the actual size of the cilia labelled A on page 41 of the article. Show your workings out and quote your answer to 2d.p. 3

4 Comprehension Questions 1. State the name of the epithelial layer found in the trachea. 2. Explain the meaning of glycoprotein and state where glycoproteins are made. 3. Explain how cilia prevent microbes reaching the lungs. 4. What is the meaning of the prefix in Lactobacillus. 5. Describe the structure of one dietary polysaccharide. 6. Explain how gut bacteria have been linked to obesity. 4

5 Internet Research The Human Microbiome Project Write an abstract of the information on the above web page of no more than 60 words. 5

6 Anticipation Guide Directions: Before you read the article Stomach Ulcers - in the first column, write A or D indicating your agreement or disagreement with each statement. As you read, compare your opinions with the information from the article. In the space under each statement, cite information form the article that supports or refutes your original ideas. Me Text Statement 1. Gastric ulcers are very common. 2. Gastric ulcers are caused by stress and eating spicy foods. 3. Reducing stomach acidity reduces the pain of a gastric ulcer. 4. Gastric ulcers are only painful after eating food. 5. It is sometimes difficult to change common medical thinking. 6. Biopsy s taken from stomach samples showed bacterial infections were associated with ulcer formation. 7. Some bacteria are classed as a class I carcinogen. 8. Bacteria can survive in the mucus layer of the stomach. 6

7 Coding Text Directions: As you read, use the symbols below to code the text in the article. Symbol Meaning Confirms what you thought X? Puzzles you?? Really confuses you Contradicts what you thought * Strikes you as very important Is new or interesting to you R A Reminds you of something Answers a question you had! Something surprises you Use this with a brief statement to show that you have made a connection to something you are already familiar with. 7

8 Comprehension Questions 1. Explain how urease allows H.pylori to survive in the stomach. 2. Explain the importance of Koch s postulates to Warren and Marshall s Investigation into gastric ulcers. 3. For many years Warren and Marshall s hypothesis that a bacterial infection was the cause of gastric ulcers was not accepted by the medical community. Evaluate the arguments put forward by medical professionals to disprove Warren and Marshall s hypothesis. 4. Explain if Warren and Marshall proved a correlation or a causal relationship between H.pylori infection and gastric ulcer formation. 8

9 Application Before the link between H.pylori infection and the formation of gastric ulcers, the treatment for gastric ulcers involved diet and lifestyle changes along with reducing stomach acid production. The diagram below summarizes how HCl is produced. 9

10 a. Name: Cell X Cell Y One other component of gastric juice, secreted by cells in the gastric glands, not shown on the diagram. b. Describe the role of the Golgi Body in cell Y. c. Describe, using only the information in the diagram, the sequence of events leading to the release of HCl. d. HCl can damage cells of the stomach, leading to the formation of a gastric ulcer. Suggest how certain antihistamine drugs, which have a similar shape to the histamine molecule, can reduce the incidence of gastric ulcers. 10

11 The synthesis of HCl in the gastric gland of the oxyntic cell requires protons and chloride ions. e i Using your own knowledge of membrane transport and the relevant inforamtion in the oxyntic cell below, explain a further mechanism by which HCl production can be inhibited in addition to antihistomine drugs. 11

12 e ii Oxyntic cell contains many mitochondria. Explain how the large number of mitochoindria are related to the function of the oxyntic cells. 12