Chapter 12 Aging and Alzheimer’s Disease

Overview

Throughout history, across most human cultures, there have been stories about people searching for the Fountain of Youth or the Elixir of Life. Similarly, the promise of some version of eternal life is common to many of the world’s religions. These universal human themes reflect the inescapable fact that life is always accompanied by aging and, eventually, death. We can all recognize the signs of aging in ourselves and our family members; consequently, many commercial products target our natural desire to slow or reverse the aging process—but why do we age? What changes occur at the cellular and molecular levels as organisms age, and why do different organisms age at different rates, leading to vastly different lifespans? In this chapter, we consider the biology of the aging process, its underlying causes at the cellular and molecular levels, and current research into how the aging process might be slowed. We briefly address the many diseases that are associated with aging and then focus on one of the most common, Alzheimer’s disease.

Chapter Outline

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Review Questions

REVIEW QUIZZES

THE PURPOSE of these review quizzes is to guide students in where their knowledge and understanding is strong, where it is weak, and where time should best be spent in studying.

CHAPTER 12:

  1. Describe at least three body functions that change with advancing age.  What is the underlying basis for these changes at the cellular and molecular levels?  Is there any way to intervene and influence these changes (and why or why not)?   (If you cannot explain these things, or if you are not sure, then you need to reread Section 12.1.)
  2. What changes in the immune system occur with advancing age?  What changes in cancer risks occur with advancing age?  Are these two phenomena related, and, if so, how?  Can anything be done to control these changes?  If so, what?  If not, why not? What are some risks and benefits of trying to control the aging process?  (If you cannot explain these things, or if you are not sure, then you need to reread Section 12.1.)
  3. In the course of Alzheimer’s disease, what changes occur early, and what changes occur later?  What specific changes occur in the brain, and how can we test for these changes?  Are there any ways to alter or influence these changes?    (If you cannot explain these things, or if you are not sure, then you need to reread Section 12.2.)
  4. What are some ways to alter a person’s risk of developing Alzheimer’s disease?  What drugs can be used to treat Alzheimer’s disease, and what are their limitations?    (If you cannot explain these things, or if you are not sure, then you need to reread Section 12.2.)
  5. What impact does Alzheimer’s disease have on the families of those afflicted with the disease?  What impact does Alzheimer’s disease have on society as a whole?  What are some broader impacts of the changing age structure of populations? (If you cannot explain these things, or if you are not sure, then you need to reread Sections 12.2 and 12.3.)

Open Response Study Questions

These questions are designed to assess your understanding of the topics explored in this chapter. You can use these questions in three ways:

Before you start …

Read through the questions before you read the chapter to help prime you to read the text more carefully and strategically. Remember that you are just starting out on your learning journey, so don’t feel disheartened if you don’t know how to answer them yet!

Whilst you read …

As you work through the chapter, have another go at answering the questions to see how you are progressing. You can also answer the questions with the textbook open in front of you, in order to create model answers that can be used to refer back to later.

At the end …

Answer the questions once you have finished reading to see what you have learned. Check your responses against your model answers and use these to identify any gaps in your understanding.

DEFINITIONS:

In your own words, define ANY TWO of the following terms:

reactive oxygen species          free radicals    progeria            sarcopenia       macrophages

beta amyloid (Aβ)                   presenilin       

ESSAYS:

Answer any two of the following questions.  Make sure to answer all parts of any question you choose.

1. Describe why caregivers who care for Alzheimer’s patients suffer more stress than caregivers for most other disease conditions.

2. Draw a diagram showing some of the important processes and pathways believed to occur in the development of Alzheimer’s disease.

3. (A) List as many voluntary measures as you can that will reduce your chances of developing Alzheimer’s disease later in life. (B) Identify which of these measures will also help slow the progression of the disease once it is acquired.

PowerPoint Slides

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Bibliography

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YouTube:  What it’s like to have AD.  Https://www.youtube.com/watch?v=LL_Gq7Shc-Y  

Chapter 13
Drugs and Addiction