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Compare and contrast the structure of the mucosal layers ofthe stomach and small intestine. What does this tell you about theroles of the stomach and small intestine within the digestivesystem? Provide a brief description of two specialized structuresfrom each organâs mucosal layer to support your discussion of itsrole.

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Hubert KochLv2

10 Jan 2019

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Itâs Friday morning and Sal Volpe is sitting in Dr. Lorraineâs exam room, dozing after another night of disrupted sleep. When the doctor knocks and walks in, she finds the 66-year-old man looking exhausted and uncomfortable. Sal gets to the reason for his visit immediately: Heâs been suffering from âstomach achesâ (dyspepsia) that wake him at night and nag him in between meals during the day. He describes his pain as gnawing, burning (maybe a 4 out of 10 on a pain scale) and points to the epigastric region of his abdomen. When he eats, he tells Dr. Lorraine, the pain goes away, but then he feels bloated and a little nauseated. The pain usually returns 2â4 hours later, depending on what he eats. Sal explains that he has had some pain relief from the over-the-counter drug PepcidÂ® (famotadine).

Dr. Lorraine proceeds with the history and physical exam. She discovers that Sal has a family history for gastrointestinal cancer and has unintentionally lost 10 pounds since his checkup a year ago. His epigastric area is modestly tender to palpation. She suspects a peptic ulcer (gastric or duodenal), but the weight loss and family history make it prudent to eliminate the diagnosis of stomach (gastric) cancer. âMr. Volpe, I think you may have a stomach or intestinal ulcer,â Dr. Lorraine says. âI suggest we perform an endoscopy to have a look. This involves passing a small tube with a small camera through your mouth and into your stomach. We can look at the wall of your stomach and small intestine, check for an ulcer, and remove a very small piece of tissue to test for infection. We call this a biopsy. Weâll also test the biopsy for cancer because of your family history. But, I really think weâre dealing with an ulcer here and not cancer.â

Later that month, the endoscopy is performed and it confirms Dr. Lorraineâs suspicions. Sal has a duodenal ulcer and infection with the bacterium Helicobacter pylori (H. pylori). This is not surprising since H. pylori is the cause of most peptic ulcer disease, particularly in the duodenum. Treatment involves complete eradication of the H. pylori with two different antibiotics, and a drug that decreases gastric acid secretion, a so-called proton pump inhibitor (PPI). Dr. Lorraine explains to Sal, âMr. Volpe, you do not have stomach cancer, but you do have a duodenal ulcer caused by the H. pylori bacteria I was telling you about. Too much acid and inflammation from this infection is causing your pain. The good news is we can probably cure your ulcer by killing the bacteria, but you will have to take three different medications twice a day for 14 days. Iâll see you again in 3 weeks; we can do a simple breath test to determine if the H. pylori has been successfully eliminated.â

Short Answer Questions:

The structures in the epigastric region share a common nerve supply. Can you name the specific cranial nerve that serves this region and the part of the nervous system to which it belongs?

In order to understand the disease in Mr. Volpeâs alimentary canal, one must know the layers that make up its walls. Design a chart that identifies the four basic layers of the alimentary canal, the tissues that make up each layer, and the general function of each layer.

Dr. Lorraine suspects a peptic ulcer. This is an inflammatory lesion in the stomach or duodenal mucosa, which may extend through all layers of the alimentary canal wall. Describe the basic histological (tissue) structure of the mucosa layer in the alimentary canal. Identify the unique features of the mucosa in the stomach and in the duodenum, and explain how this uniqueness determines the function of the stomach and the duodenum.

Mr. Volpe asks, âWhat do the bacteria have to do with the ulcer?â Dr. Lorraine tells him that the H. pylori increases stomach acid secretion and, at the same time, breaks down the lining of your stomach and duodenum. What is the source and normal function of acid in the stomach and what regulates its production

Why is Mr. Volpeâs dyspepsia relieved by food, and aggravated 2â4 hours after a meal?

coffeesheep473

I JUST NEED SIMPLE/BASIC ANSWERS NOT LONG ANSWERS

1. Explain how life can be viewed at different levels of biological complexity.

2. Explain how researchers study biology at different levels, ranging from molecules to ecosystems.

3. Distinguish between discovery-based science and hypothesis testing, and describe the steps of the scientific method.

4. Tell whether a given topic or research study is about biology. Tell whether that study is discovery-based or hypothesis testing, or both.

5. If presented with a research study, propose what the Research Question was.

6. If presented with an example, tell whether a statement is a hypothesis, theory or law and why you think so.

Describe the general structure of atoms and their constituent particles.

Relate atomic structure to the periodic table of the elements. List the elements that make up most of the mass of all living organisms.

Explain how a single element may exist in more than one form, called isotopes, and how certain isotopes have importance in human medicine.

Compare and contrast the types of atomic interactions (bonds) that lead to the formation of molecules.

Tell which atoms and how many of each make up a given molecule (formula or diagram).

For a bond in a given molecule, tell whether the bond is covalent, and if it is, tell whether it is polar or nonpolar and why you think so.

Explain the concept of electronegativity and how it contributes to the formation of polar and nonpolar covalent bonds. Tell whether a given atom is electronegative or not, and why you think so. Label partial charges in a polar bond.

Draw five water molecules and label the atoms and bonds within and between the 5 molecules.

Describe how hydrogen bonding determines many properties of water.

List the properties of water that make it a valuable solvent, and distinguish between hydrophilic and hydrophobic substances.

Explain how water has the ability to ionize into hydroxide ions (OH^â) and into hydrogen ions (H⁺), and how the H⁺ concentration is expressed as a solution's pH.

Explain the properties of carbon that make it the chemical basis of all life.

Describe the variety and chemical characteristics of common functional groups of organic compounds.

Diagram how small molecules may be assembled into larger ones by dehydration reactions and how hydrolysis reactions can reverse this process.

List the four major classes of organic molecules and macromolecules found in living organisms

If shown a molecule, tell whether it is organic or not and how you know.

If shown an organic molecule, tell whether it is an amino acid, nucleotide, fatty acid, steroid, monosaccharide or disaccharide and how you know.

Distinguish among different forms of carbohydrate molecules, including monosaccharides, disaccharides, and polysaccharides.

Relate the functions of plant and animal polysaccharides to their structure.

List the several different classes of lipid molecules important in living organisms.

Diagram the structure of a triglyceride and explain how it is affected by the presence of saturated and unsaturated fatty acids. Explain why some fats are solid at room temperature, and others are liquid.

Discuss how fats function as energy-storage molecules.

Apply knowledge of the structure of phospholipids to the formation of cellular membranes.

Describe the chemical nature of steroids and give an example of their biological importance.

Give examples of the general types of functions that are carried out in cells by different types of proteins.

Explain how amino acids are joined to form a polypeptide, and distinguish between a polypeptide and protein.

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Outline the bonding forces important in determining protein shape and function.

Explain what domains are and their importance in proteins.

Describe the three components of nucleotides.

Distinguish between the structures of DNA and RNA.

Tell how certain bases pair with others in DNA and RNA.

Discuss the 4 major categories of organic macromolecules found in living things, including structure, function and location of each.

Compare and contrast the general structural features of prokaryotic and eukaryotic cells.

Outline the differences in complexity among bacteria, animal, and plant cells.

Describe how a eukaryotic cell can be viewed as four interacting systems: the nucleus, cytosol, endomembrane system, and semiautonomous organelles.

Explain how the proteome underlies the structure and function of cells.

Analyze how cell size and shape affect the surface area/volume ratio.

Identify the location of the cytosol in a eukaryotic cell and list its general functions.

Describe the three types of protein filaments that make up the cytoskeleton. Identify which underlie cilia, flagella, centrioles, the nuclear lamina, and the brush border. Tell which are readily assembled and disassembled. Tell which are involved in various cell shape changes or movements.

Explain how motor proteins interact with microtubules or actin filaments to promote cellular movement.

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Distinguish between the rough endoplasmic reticulum and the smooth endoplasmic reticulum.

Identify three important functions of the plasma membrane.

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Outline the structures and general functions of mitochondria and chloroplasts.

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Sketch and label a âtypicalâ plant cell and a real plant cell such as a root or leaf cell. Tell how it might be different than the âtypicalâ cell in terms of its organelles and shape.

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61. Name all the places in a cell where membranes are found.

62. Describe at least three different categories of membrane proteins and tell what they do.

63. Describe what determines how fluid membranes are.

64. Explain how lipids are synthesized at the ER membrane.

65. Explain how transmembrane proteins are inserted into the ER membrane.

66. Compare and contrast diffusion, facilitated diffusion, passive transport, and active transport.

67. Explain the process of osmosis and how it affects cell structure.

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69. Explain the difference between primary active transport and secondary active transport.

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Discuss membrane transport, including its function and various forms and why all membranes have each form.

73. If a given cellular process is described, tell which form of transport might be involved.

List the different categories of animal tissue, providing general functions and specific examples of each.

Name the various organ systems found in many animals, list the components of each, and describe their general functions.

bluebeaver798

To complete the scenario section of the final, choose a scenario and paste it where indicated below. You may delete the other scenarios from the body of the exam. Answer the questions regarding the study you designed, giving the answers following each of the questions. If one of the questions isnât applicable to your study, respond N/A after the question. Any additional information about the study youâve designed can be added at the end of the required questions and will likely generate some extra points.

Design an epidemiological study for only ONE of the 6 scenarios below and provide at minimum the following information about your study:

Scenario 1: A new vaccine (NoBola) has been developed to prevent Ebola. Design a study that will indicate whether or not NoBola is associated with a reduction in Ebola cases in parts of the world where Ebola is endemic.

Please answer the above questions

1â¢ Describe how you will recruit or identify study participants to best represent the target population

2â¢ Describe the risks and benefits of participating in the study

3â¢ Provide a case definition (e.g. in a cohort study, how will you diagnose those who become ill, in a case-control or cross-sectional study, what characteristics does the participant need to have to be considered a case)

4â¢ Describe exposures or risk factors and how you will measure them

5â¢ Describe exclusion criteria (e.g. in a prospective cohort study, a person who tests positive for illness at or near baseline must be excluded)

6â¢ Describe how you will collect data for your study (survey, medical records, laboratory tests, etc.)

7â¢ Divide subjects as appropriate for your study design (i.e. exposed/unexposed, case/control)

8â¢ Describe outcome measure for study, how itâs calculated, and how itâs to be interpreted (you donât need to actually do calculations, but provide the equations and give an example of how theyâre interpreted): For example: RR=a/(a+b) interpreted as the risk of lung cancer in smokers is X times greater (or less) than it is in non-smokers

9â¢ Give justification for your study design (tell why you chose that particular study design, why it is appropriate, and what you hoped to learn from doing the study)

10â¢ Brief discussion of study strengths and weaknesses including a discussion of causal hypotheses and biases as they relate to your study design