From a public health standpoint, why is there so much attention paid to increasing a sedentary person’s physical activity by a small amount rather than suggesting strenuous exercise? 

2. How do elderly people respond to exercise training compared to younger adults?

3. What is the effect of exercise on appetite and body composition?

4. What is the role of environmental factors, such as altitude and heat, in very long distance performances of one to four hours duration?

Question #1 (16 Points)

Tom is a molecular biology graduate student who needs to isolate a gene from the

pathogenic bacteria Salmonella typhi, which he is studying. He wisely decides to use PCR to

amplify the gene before trying to purify it. The gene has the general structure shown below:

~1000 Base Pairs

! ! 5′-ATGGCTTACGTG———–CCATAGGGCTAA-3′

! ! 3′-TACCGAATGCAC———–GGTATCCCGATT-5′

The gene is about 1000 nucleotide base pairs long, but only the sequences at the ends of

the double strand are shown. Use the information from the video, what you learned about base

pairing in class, and the fact that PCR always proceeds along the parent DNA strand the 3′ to 5′

direction. Design two, 6-nucleotide long, PCR primers for Tom.

a) What different components will do you want to add to your PCR?

a) Template DNA and DNA Polymerase b) Template DNA and Primers c) Template DNA, Primers and DNA Polymerase

Like Carlos, most patients with HUS will recover, though some may have lasting complications from renal failure. His case represents a fairly typical presentation of HUS, which usually occurs in young children after ingestion of food or water containing E. coli O157: H7. Though HUS is relatively rare, cases of HUS tend to receive a great deal of media publicity because of the public health implications of E. coli-contaminated food or water. Proper intervention has reduced the mortality from this disease from nearly 100% in the 1950s to 3-5% in the 1990s. The prognosis depends largely on prompt recognition of the problem and aggressive management of its complications, as we saw with this case.

With Carlos’ case of renal failure being due to a gastrointestinal infection with E.coli O157: H7, we saw yet again the interrelatedness all of the systems of the body—not one functions as a stand-alone system. Carlos’ disease, which began as a gastrointestinal illness, impacted multiple systems, including the urinary, cardiovascular, immune, and respiratory systems.

We also saw the interrelatedness of all of the functions of the urinary system. HUS primarily impacts one process of the urinary system—glomerular filtration. However, in impairing the kidneys’ ability to filter blood at the glomerulus, HUS also prevents the kidneys from performing their two other main processes, tubular reabsorption and secretion. When Carlos’ GFR decreased and his kidneys entered renal failure, not only did waste products accumulate in his blood, but his kidneys were also no longer able to regulate his fluid, electrolyte, and acid-base balance.

This case also demonstrated another important principle that we’ve revisited throughout this text: the interrelatedness of form and function. When the glomerular capillaries lost their form due to attack from the E. coli O157: H7 toxin, they were no longer able to carry out their function of blood filtration. Can you think of other examples of the form follows function principle from this case?

Placing a urinary catheter into Carlos’ urinary bladder is a bit more challenging since he is a male. What difference between the male and female urethra explains the difficulty?

Like Carlos, most patients with HUS will recover, though some may have lasting complications from renal failure. His case represents a fairly typical presentation of HUS, which usually occurs in young children after ingestion of food or water containing E. coli O157: H7. Though HUS is relatively rare, cases of HUS tend to receive a great deal of media publicity because of the public health implications of E. coli-contaminated food or water. Proper intervention has reduced the mortality from this disease from nearly 100% in the 1950s to 3-5% in the 1990s. The prognosis depends largely on prompt recognition of the problem and aggressive management of its complications, as we saw with this case.

With Carlos’ case of renal failure being due to a gastrointestinal infection with E.coli O157: H7, we saw yet again the interrelatedness all of the systems of the body—not one functions as a stand-alone system. Carlos’ disease, which began as a gastrointestinal illness, impacted multiple systems, including the urinary, cardiovascular, immune, and respiratory systems.

We also saw the interrelatedness of all of the functions of the urinary system. HUS primarily impacts one process of the urinary system—glomerular filtration. However, in impairing the kidneys’ ability to filter blood at the glomerulus, HUS also prevents the kidneys from performing their two other main processes, tubular reabsorption and secretion. When Carlos’ GFR decreased and his kidneys entered renal failure, not only did waste products accumulate in his blood, but his kidneys were also no longer able to regulate his fluid, electrolyte, and acid-base balance.

This case also demonstrated another important principle that we’ve revisited throughout this text: the interrelatedness of form and function. When the glomerular capillaries lost their form due to attack from the E. coli O157: H7 toxin, they were no longer able to carry out their function of blood filtration. Can you think of other examples of the form follows function principle from this case?

Placing a urinary catheter into Carlos’ urinary bladder is a bit more challenging since he is a male. What difference between the male and female urethra explains the difficulty?

a. The sphincter at the external urethral orifice is more muscular in the male than the female.

b. The male urethra is longer than the female urethra and curves near the membranous portion.

c. The spongy urethra is narrower in the male urethra than it is in the female urethra.

d. The female urethra is longer than the male urethra, because it must travel anterior to the uterus to reach the eternal urethral orifice.