A&S300	Spring 2006						Name:
Final Exam

You may NOT use any books, notes, or related materials to complete this exam.  
Give brief answers!

1. (2 pts).  Mean human lifespan has increased greatly in the US over the past century.  What has caused this?  I’m not looking for specific disease treatments or medical advances, but how has the shape of the human survival curve changed?  For example, has maximum human lifespan increased?

2. (3 pts).  List 3 diseases of aging.

3. (3 pts) In class we have discussed reasons why aging occurs as well as the organismal and cellular processes responsible for aging.  This question is about what causes aging or how animals age but rather about why aging occurs in animals at all.  Briefly describe why animals age including the evolutionary forces that lead to aging.

4. (3pts) Indicate which label goes with which human population survival curve below.
1) US 1900
2) US 1960
3) All diseases cured.
4) Romans, 300 AD.

A

B

C

D

5. (2 pts)  What does the acronym AGEs stand for and what are AGEs?

6. (2pts)  Describe the role of AGEs in the aging process.

7. (2 pts) Why do the mitochondria play a central role in free radical/oxidative stress theories of aging?

8. (2 pts).  What is a stem cell?  How does it differ from a “normal” cell?

9. (3 pts).  Describe a) changes in stem cells with aging and b) the effects on the organism due to stem cell aging.
a)

b)

10. (2 pts).  Name a small molecule (a drug) that can extend lifespan and identify the pathway it acts through.

11. (1 pts).  What do SOD, catalase, and GSH have in common?

12a. (2 pts).  What purpose does the Hayflick limit on cell division serve in animals?

12b. (2 pts).  Describe the mechanism(s) through which short telomeres cause cells to stop dividing and senesce.

13. (1 pt).  How heritable is human lifespan?  Give the heritability figure or describe it with an appropriate range (less heritable than X and more heritable than Y).

14a. (2 pt).  What are two environmental or lifestyle factors correlated with premature aging?

14b. (2 pt).  What are two environmental or lifestyle factors correlated with a long lifespan?

15. (3 pts).  What is the molecular function of heat shock proteins and what role do they play in the aging process?

16. (2 pts).  Microarray experiments assay the expression level of nearly every gene simultaneously.  In microarray experiments comparing young/old animals, senescent/diving cells, or long-lived/wt animals which genes types or gene classes have shown altered expression? 

17. (3 pts).  Describe the mechanisms through which caloric restriction acts to extend lifespan.

18.  Describe one of the long-lived mouse aging models (other than caloric restriction or the insulin receptor (Insr) knockout).
18a. (1 pts)  What gene is mutated, knocked out , or overexpressed in this aging model?

18b. (3 pts)  How does this the defect in this gene result in lifespan extension?  That is, how does loss of  gene affect the animal and through which aging pathway does it act?

19. (2 pts).  Describe the role of stem cells in normal aging.

20. (2 pts).  Describe two anti-aging treatments under investigation with prospects to 
extend human lifespan or reverse aging in the next 20 years.
1.

2.

  
21. (3 pts) Figure 1 from Calorie restriction extends Saccharomyces cerevisiae lifespan by increasing respiration, Lin et al. 2002 is shown below for reference.  Label the strains A, B, and C in Fig. 2:

1) WT + v						5) WT, 2% glucose
2) WT + HAP4 overexpression 			6) WT, 0.5% glucose
3) cyt1 deletion + v					7) cyt1 deletion, 2% glucose
4) cyt1 deletion + HAP4 overexpression 		8) cyt1 deletion, 0.5% glucose

Fig. 1.  Lifespan analysis of cells grown on media containing 0.5% and 2% glucose.  Brown pigment indicates silencing at the rDNA locus.

	

Fig. 2.  Note: cytochrome c1 (CYT1) deletion disrupts electron transport.

C

 A

 B