Biology 120
Exam No. 4 Spring 1998
Name__________________
BY
PLACING MY NAME ON THE ANSWER SHEET THAT IS ATTACHED TO THIS EXAM, I ACKNOWLEDGE
THAT I AM AWARE OF THE ACADEMIC DISHONESTY POLICY THAT
IS IN EFFECT FOR THIS CLASS.
1.
What percent of the daily intake of calories comes from fat for persons
living in the United States?
2.
True or False Human diets
have not changed substantially in the last 5,000 years.
3.
True or False Modern humans
have existed on a low-fat and high-fiber diet for thousands of years and are
still physiologically adapted to such a diet.
4.
True or False Breast cancer
is more common in nuns than in women who lead conventional lives.
5.
True or False One exposure
to a cancer initiator may be sufficient to begin the process that results in
cancer.
6.
What is the average latent period for cancers in humans?
7.
What substance is associated with a large percent of human lung cancers?
8.
What dietary item is most clearly established as a cancer promoter?
9.
True or False Breast cancer
is more common in people in the United States than in Japan because of genetic
differences in the people.
10. What type of diet is most likely to result in laboratory rats
having cancer?
11. Name the non-cellular material that lines the stomach.
12. Name the first section of the small intestine (i.e., the
section of the small intestine leading away from the stomach).
13. True or False All
people who have high levels of stomach acid acquire ulcers.
14. True or False Some
medications, such as aspirin, can cause ulcers.
15. True or False Virtually
all persons with duodenal ulcers have Helicobacter pylori present
in the duodenum.
16. What is the most feasible way of overcoming Helicobacter
pylori infections and gastritis?
A.
surgery; B. diet;
C. antibiotics; D. exercise
17. What proportion of the world’s population is infected with Helicobacter
pylori ?
A.
less than 10%; B. about 75%; C. nearly 100%; D.
33-50%
18. How can a blood test be used to determine whether or not a
person is infected with Helicobacter pylori ?
A.
detects antigens from H. pylori;
B. detects antibodies to H. pylori;
C. counts numbers of H. pylori present;
D. measures the amount of toxin released by H. pylori
19. Name the enzyme that breaks urea into ammonia and carbon
dioxide.
A.
urea; B. uric acid; C.
urease; D. ammoniase
20. True or False All
genetic strains of Helicobacter pylori are equally toxigenic.
21--50. Protein digestion and nitrogen excretion
A Biology 120 student named Joe is about 25 years old. Joe eats a hamburger. Mechanical
digestion of the proteins in the hamburger will begin in the mouth as the 12
teeth known as 21 mechanically cut apart and reduce the size of the food
particles. A carbohydrase called 22
will be added to the food in the mouth; this enzyme 23 (A. will;
B. will not) chemically digest proteins.
Since Joe is a normal person, he possesses 24 (3, 6, 9, 12)
salivary glands. The saliva that is
added to the food in the mouth contains a liquid called 25 that is
essential for hydrolysis of all of the food groups, including proteins.
The proteins, along with the other components of Joe’s hamburger, will
move from his mouth into a tube called the 26 which empties into the
stomach. At the entrance to the
stomach is a band of circular muscles called a 27 which regulates the
movements of materials into the stomach.
Chemical digestion of proteins will begin in the stomach when an enzyme
called 28 is added to the food. This
enzyme will function best at a(n) 29 (acid, basic, neutral) pH.
The pH of the stomach is strongly influenced by an acid named 30,
whose presence is necessary for chemical digestion in the stomach.
The stomach is lined with a secreted material called 31 which
helps prevent digestion of the stomach walls.
The partially digested materials will move from the stomach into the
small intestine where chemical digestion of most food groups will be completed. Some animals, especially those that eat 32 (plants,
animals) have considerable digestion (by bacteria) in a structure called the 33
which is a dead-end structure that originates at the junction of the small
intestine and large intestine. (The
tip of the structure named in question 33 is called the 34 in humans and
is most frequently mentioned because of problems that may originate there.)
Chemical digestion of proteins will be completed in Joe’s small
intestine. At this point, the
proteins have been digested into their “building blocks” which are called 35.
These products of protein digestion will enter the blood stream through
the walls of the body organ named the 36.
The products of protein digestion will initially enter a type of blood
vessel called a(n) 37 (artery, vein, capillary); a larger vessel called
the 38 will drain blood from the small intestine and deliver blood to the
body organ named the 39.
Joe needs nitrogen for maintaining and repairing tissues (among other
functions). Like other normal
humans, Joe takes in more nitrogen than he needs; much of this excess nitrogen
is in the protein that Joe eats. If
we study the digestion of his proteins, we learn that in a body organ named the 40
many of Joe’s amino acids will be deaminated.
In the process of deamination, a group named the 41 (hydrogen,
amino, carboxyl, R) will be removed from each amino acid; two of these groups
are then used by the body organ named the 42 to manufacture a molecule
called 43 which is the primary form in which humans excrete nitrogen.
The body organ named in question 40 is drained by a blood vessel named
the 44 which delivers blood to the vena cava.
Eventually (after passing through the heart and lungs) the blood will
arrive at the kidneys where the molecules named in question 43 will be removed
from the blood.
The functional units of each of Joe’s kidneys are called 45.
Much of the liquid part of the blood, which is called 46, will
enter Bowman’s capsule from the glomerulus.
Materials can then be selectively pumped either into or out of the blood
as it circulates through the kidneys. The
product of a kidney, which is called urine, will exit the kidney in a tube named
the 47; this tube leads to a storage structure called the 48.
From this storage structure, a tube named the 49 provides a
passageway for the urine (containing excess nitrogen) to leave Joe’s body.
On a typical day, Joe will probably excrete from his body about 50
(1, 5, 10, 125) quarts of urine.