Because dental caries (decay) is strongly linked to consumption of the

Question

Passage A

Because dental caries (decay) is strongly linked to
consumption of the sticky, carbohydrate-rich staples of
agricultural diets, prehistoric human teeth can provide
clues about when a population made the transition
  (5)   from a hunter-gatherer diet to an agricultural one.
Caries formation is influenced by several factors,
including tooth structure, bacteria in the mouth, and
diet. In particular, caries formation is affected by
carbohydrates’ texture and composition, since
  (10)   carbohydrates more readily stick to teeth.

Many researchers have demonstrated the link
between carbohydrate consumption and caries. In
North America, Leigh studied caries in archaeologically
derived teeth, noting that caries rates differed between
  (15)   indigenous populations that primarily consumed meat
(a Sioux sample showed almost no caries) and those
heavily dependent on cultivated maize (a Zuni sample
had 75 percent carious teeth). Leigh’s findings have
been frequently confirmed by other researchers, who
  (20)   have shown that, in general, the greater a 
population’s dependence on agriculture is, the higher 
its rate of caries formation will be.

Under some circumstances, however,
nonagricultural populations may exhibit relatively
  (25)   high caries rates. For example, early nonagricultural
populations in western North America who consumed
large amounts of highly processed stone-ground flour
made from gathered acorns show relatively high caries
frequencies. And wild plants collected by the Hopi
  (30)   included several species with high cariogenic
potential, notably pinyon nuts and wild tubers.

Passage B

Archaeologists recovered human skeletal remains
interred over a 2,000-year period in prehistoric
Ban Chiang, Thailand. The site’s early inhabitants
  (35)   appear to have had a hunter-gatherer-cultivator
economy. Evidence indicates that, over time, the
population became increasingly dependent on
agriculture.

Research suggests that agricultural intensification
  (40)   results in declining human health, including dental
health. Studies show that dental caries is uncommon in
pre-agricultural populations. Increased caries frequency
may result from increased consumption of starchy-sticky
foodstuffs or from alterations in tooth wear. The
  (45)   wearing down of tooth crown surfaces reduces caries
formation by removing fissures that can trap food
particles. A reduction of fiber or grit in a diet may
diminish tooth wear, thus increasing caries frequency.
However, severe wear that exposes a tooth’s pulp
  (50)   cavity may also result in caries.

The diet of Ban Chiang’s inhabitants included
some cultivated rice and yams from the beginning of
the period represented by the recovered remains.
These were part of a varied diet that also included
  (55)   wild plant and animal foods. Since both rice and yams
are carbohydrates, increased reliance on either or both
should theoretically result in increased caries frequency.

Yet comparisons of caries frequency in the Early
and Late Ban Chiang Groups indicate that overall
  (60)   caries frequency is slightly greater in the Early Group.
Tooth wear patterns do not indicate tooth wear
changes between Early and Late Groups that would
explain this unexpected finding. It is more likely that,
although dependence on agriculture increased, the diet
  (65)   in the Late period remained varied enough that no
single food dominated. Furthermore, there may have
been a shift from sweeter carbohydrates (yams) toward
rice, a less cariogenic carbohydrate.    1 
 1. Both passages are primarily concerned with examining which one of the following topics?

(A) evidence of the development of agriculture in the archaeological record
(B) the impact of agriculture on the overall health of human populations
(C) the effects of carbohydrate-rich foods on caries formation in strictly agricultural societies
(D) the archaeological evidence regarding when the first agricultural society arose
(E) the extent to which pre-agricultural populations were able to obtain carbohydrate-rich foods

2 
 2. Which one of the following distinguishes the Ban Chiang populations discussed in passage B from the populations discussed in the last paragraph of passage A?

(A) While the Ban Chiang populations consumed several highly cariogenic foods, the populations discussed in the last paragraph of passage A did not.
(B) While the Ban Chiang populations ate cultivated foods, the populations discussed in the last paragraph of passage A did not.
(C) While the Ban Chiang populations consumed a diet consisting primarily of carbohydrates, the populations discussed in the last paragraph of passage A did not.
(D) While the Ban Chiang populations exhibited very high levels of tooth wear, the populations discussed in the last paragraph of passage A did not.
(E) While the Ban Chiang populations ate certain highly processed foods, the populations discussed in the last paragraph of passage A did not

3 
 3. Passage B most strongly supports which one of the following statements about fiber and grit in a diet?

(A) They can either limit or promote caries formation, depending on their prevalence in the diet.
(B) They are typically consumed in greater quantities as a population adopts agriculture.
(C) They have a negative effect on overall health since they have no nutritional value.
(D) They contribute to the formation of fissures in tooth surfaces.
(E) They increase the stickiness of carbohydraterich foods.

4 
 4. Which one of the following is mentioned in both passages as evidence tending to support the prevailing view regarding the relationship between dental caries and carbohydrate consumption?

(A) the effect of consuming highly processed foods on caries formation
(B) the relatively low incidence of caries among nonagricultural people
(C) the effect of fiber and grit in the diet on caries formation
(D) the effect of the consumption of wild foods on tooth wear
(E) the effect of agricultural intensification on overall human health

5 
 5. It is most likely that both authors would agree with which one of the following statements about dental caries?

(A) The incidence of dental caries increases predictably in populations over time.
(B) Dental caries is often difficult to detect in teeth recovered from archaeological sites.
(C) Dental caries tends to be more prevalent in populations with a hunter-gatherer diet than in populations with an agricultural diet.
(D) The frequency of dental caries in a population does not necessarily correspond directly to the population’s degree of dependence on agriculture.
(E) The formation of dental caries tends to be more strongly linked to tooth wear than to the consumption of a particular kind of food.

6 
 6. Each passage suggests which one of the following about carbohydrate-rich foods?

(A) Varieties that are cultivated have a greater tendency to cause caries than varieties that grow wild.
(B) Those that require substantial processing do not play a role in hunter-gatherer diets.
(C) Some of them naturally have a greater tendency than others to cause caries.
(D) Some of them reduce caries formation because their relatively high fiber content increases tooth wear.
(E) The cariogenic potential of a given variety increases if it is cultivated rather than gathered in the wild.

7 
 7. The evidence from Ban Chiang discussed in passage B relates to the generalization reported in the second paragraph of passage A (lines 20–22) in which one of the following ways?

(A) The evidence confirms the generalization.
(B) The evidence tends to support the generalization.
(C) The evidence is irrelevant to the generalization.
(D) The evidence does not conform to the generalization.
(E) The evidence disproves the generalization.

Sajjad1994 · Answer

Explanation

1. Both passages are primarily concerned with examining which one of the following topics?

Difficulty Level:   700+

Explanation

This is a hard question. I had to check a few of the answers against the passage. I found  B  and  C  tempting, but they both contain terms that don’t match the passages.

(A) CORRECT.  See  lines 3-5  in  passage A , and  36-38  in  passage B.  I don’t love this answer, because I’m not sure passage B is  “primarily concerned”  with the agricultural record. They seem more specifically concerned with the tooth health of the Ban Chiang populations. But passage B is at least concerned with the development of agriculture in that population, so this is the best answer.

(B) “Overall health”  is why this is wrong. Both passages were only concerned with tooth decay.

(C) “Strictly agricultural societies”  is why this is wrong. Passage A talks about tooth decay in nonagricultural populations (paragraph 3) and passage B says the Ban Chiang groups were not entirely agricultural – they ate some wild foods  (lines 54-54).

(D)  Neither passage mentions the first agricultural society. Passage B, in particular, only talks about Thailand.

(E)  This is a general answer. Neither passage talks about hunter-gatherer carbohydrate availability in general.

Answer: A

Nielgmat · Answer

2. Which one of the following distinguishes the Ban Chiang populations discussed in passage B from the populations discussed in the last paragraph of passage A?

(A) While the Ban Chiang populations consumed several highly cariogenic foods,  the populations discussed in the last paragraph of passage A did not.   The bold portion is the opposite of what the last para of Passage A says..

(B) While the Ban Chiang populations ate cultivated foods, the populations discussed in the last paragraph of passage A did not.
  Ban Chiang populations ate cultivated foods - Yes
 populations discussed in the last paragraph of passage A did not. - True. They did not eat cultivated food. They ate 'gathered' food. 
 CORRECT answer.

(C) While the Ban Chiang populations consumed a diet consisting primarily of carbohydrates, (No. The passage does not say so. It just says they relied on agriculture)  the populations discussed in the last paragraph of passage A did not.  They depended on gathered food. whether that food contained carbs is not commented upon.

(D) While the Ban Chiang populations exhibited very high levels of tooth wear, the populations discussed in the last paragraph of passage A did not  (Last para of Passage A does not comment on tooth wear) .

(E) While the Ban Chiang populations ate  certain highly processed foods   (No mention of processed food) , the populations discussed in the last paragraph of passage A did not

Nielgmat · Answer

3. Passage B most strongly supports which one of the following statements about fiber and grit in a diet?

(I got this one wrong. Chose D as I misunderstood it. )

(A) They can either limit or promote caries formation, depending on their prevalence in the diet.
 Yes. Consumption of fiber and grit can increase tooth wear so as to remove fissures, resulting in prevention of trapping food particles. On the other hand, too much consumption of the same can increase wear to an extent that it exposes a tooth’s pulp
and cavity may also result in caries. -  CORRECT

(B) They are typically consumed in greater quantities as a population adopts agriculture.
 They did shift towards agriculture, but no comments in the passage on fiber or grit content.

(C) They have a negative effect on overall health since they have no nutritional value.
 No comment on nutritional value.

(D) They contribute to the formation of fissures in tooth surfaces.
 The opposite is true. Fiber increases tooth wear and removes fissures.  This is what I misread/misunderstood.

(E) They increase the stickiness of carbohydrate rich foods.
 Trap. Stickiness is not attributed to Fiber or grit.

Sajjad1994 · Answer

Explanation

4. Which one of the following is mentioned in both passages as evidence tending to support the prevailing view regarding the relationship between dental caries and carbohydrate consumption?

Difficulty Level:   700

Explanation

The question asks you to determine which answer choice is mentioned in both passages as evidence tending to support the prevailing view regarding the relationship between dental caries and carbohydrate consumption. Both passages indicate dental caries increases as carbohydrate consumption increases.

A. No.  This states the effect of consuming highly processed foods on caries formation. Highly processed foods are mentioned only at the end of passage A.

B.  Yes.   This states the relatively low incidence of caries among nonagricultural people. The end of the second paragraph of passage A and the beginning of the second paragraph of passage B both indicate there is a low caries rate in nonagricultural people.

C. No.  This states the effect of fiber and grit in the diet on caries formation. This is discussed only in passage B.

D. No.  This states the effect of the consumption of wild foods on tooth wear. Both passages mention wild foods, but neither one indicates there is an exact effect on tooth wear.

E. No.  This states the effect of agricultural intensification on overall human health. The passages don’t address overall human health.

Answer: B

Sajjad1994 · Answer

Explanation

6. Each passage suggests which one of the following about carbohydrate-rich foods?

Difficulty Level:   700

Explanation

The question asks you to determine which answer choice is something suggested by both passages about carbohydrate-rich foods. So, you want something supported by both passages.

A. No.  This states varieties that are cultivated have a greater tendency to cause caries than varieties that grow wild. At the end of passage A, certain wild plants are said to have high cariogenic potential, but no comparison is made to cultivated foods. Since passage A doesn’t support this statement, this can’t be correct.

B. No.  This states those that require substantial processing do not play a role in hunter-gatherer diets. The final paragraph of passage A describes a hunter gatherer population that consumes highly processed stone-ground flour.

C.  Yes.   This states some of them naturally have a greater tendency than others to cause caries. Passage A states in the first paragraph that caries formation is affected by carbohydrates’ texture and composition since carbohydrates more readily stick to teeth. Passage B states in the third paragraph that increased reliance on rice or yams, or both, should theoretically result in increased caries frequency.

D. No.  This states some of them reduce caries formation because their relatively high fiber content increases tooth wear. Passage A does not discuss fiber.

E. No.  This states the cariogenic potential of a given variety increases if it is cultivated rather than gathered in the wild. Neither passage gives any indication as to how cariogenic potential may be increased.

Answer: C

Because dental caries (decay) is strongly linked to consumption of the

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Because dental caries (decay) is strongly linked to consumption of the

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