Regents Examination in Living Environment: Questions & Answers On Standard 1 - Purpose of Scientific Inquiry

Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to pose questions, seek answers, and develop solutions.

Key Idea 1—Purpose of Scientific Inquiry
The central purpose of scientific inquiry is to develop explanations of natural phenomena in a continuing and creative process.

Sample questions

Base your answers to questions 1 through 4 on the passage below and on your knowledge of biology.
 

To Tan or Not to Tan
Around 1870, scientists discovered that sunshine could kill bacteria. In 1903, Niels Finsen, an Icelandic researcher, won the Nobel Prize for his use of sunlight therapy against infectious diseases. Sunbathing then came into wide use as a treatment for tuberculosis, Hodgkin’s disease (a form of cancer), and common wounds. The discovery of vitamin D, the “sunshine vitamin,” reinforced the healthful image of the Sun. People learned that it was better to live in a sun-filled home than a dark dwelling. At that time, the relationship between skin cancer and exposure to the Sun was not known.
In the early twentieth century, many light-skinned people believed that a deep tan was a sign of good health. However, in the 1940s, the rate of skin cancer began to increase and reached significant proportions by the 1970s. At this time, scientists began to realize how damaging deep tans could really be.
Tanning occurs when ultraviolet radiation is absorbed by the skin, causing an increase in the activity of melanocytes, cells that produce the pigment melanin. As melanin is produced, it is absorbed by cells in the upper region of the skin, resulting in the formation of a tan. In reality, the skin is building up protection against damage caused by the ultraviolet radiation. It is interesting to note that people with naturally dark skin also produce additional melanin when their skin is exposed to sunlight.
Exposure to more sunlight means more damage to the cells of the skin. Research has shown that, although people usually do not get skin cancer as children, each time a child is exposed to the Sun without protection, the chance of that child getting skin cancer as an adult increases.
Knowledge connecting the Sun to skin cancer has greatly increased since the late 1800s. Currently, it is estimated that ultraviolet radiation is responsible for more than 90% of skin cancers. Yet, even with this knowledge, about 2 million Americans use tanning parlors that expose patrons to high doses of ultraviolet radiation. A recent survey showed that at least 10% of these people would continue to do so even if they knew for certain that it would give them skin cancer.
Many of the deaths due to this type of cancer can be prevented. The cure rate for skin cancer is almost 100% when it is treated early. Reducing exposure to harmful ultraviolet radiation helps to prevent it. During the past 15 years, scientists have tried to undo the tanning myth. If the word “healthy” is separated from the word “tan,” maybe the occurrence of skin cancer will be reduced.
State one known benefit of daily exposure to the Sun. [1]

1. Explain what is meant by the phrase “the tanning myth.” [1]

2. Which statement concerning tanning is correct?
Tanning causes a decrease in the ability of the skin to regulate body temperature.
Radiation from the Sun is the only radiation that causes tanning.
The production of melanin, which causes tanning, increases when skin cells are exposed to the Sun.
Melanocytes decrease their activity as exposure to the Sun increases, causing a protective coloration on the skin.

3. Which statement concerning ultraviolet radiation is not correct?
It may damage the skin.
It stimulates the skin to produce antibodies.
It is absorbed by the skin.
It may stimulate the skin to produce excess pigment.

4. Current knowledge concerning cells is a result of the investigations and observations of many scientists. The work of these scientists forms a well-accepted body of knowledge about cells. This body of knowledge is an example of a
hypothesis
controlled experiment
theory
research plan

5. In his theory of evolution, Lamarck suggested that organisms will develop and pass on to offspring variations that they need in order to survive in a particular environment. In a later theory of evolution, Darwin proposed that changing environmental conditions favor certain variations that promote the survival of organisms. Which statement is best illustrated by this information?
Scientific theories that have been changed are the only ones supported by scientists.
All scientific theories are subject to change and improvement.
Most scientific theories are the outcome of a single hypothesis.
Scientific theories are not subject to change.

Base your answers to questions 7 and 8 on the passage below and on your knowledge of biology.
The number in the parentheses ( ) at the end of a sentence is used to identify that sentence.
 

They Sure Do Look Like Dinosaurs
When making movies about dinosaurs, film producers often use ordinary lizards and enlarge their images many times (1). We all know, however, that although they look like dinosaurs and are related to dinosaurs, lizards are not actually dinosaurs (2).
Recently, some scientists have developed a hypothesis that challenges this view (3). These scientists believe that some dinosaurs were actually the same species as some modern lizard that had grown to unbelievable sizes (4). They think that such growth might be due to a special type of DNA called repetitive DNA, often referred to as “junk” DNA because scientists do not understand its functions (5). These scientists studied pumpkins that can reach sizes of nearly 1,000 pounds and found them to contain large amounts of repetitive DNA (6). Other pumpkins that grow to only a few ounces in weight have very little of this kind of DNA (7). In addition, cells that reproduce uncontrollably have almost always been found to contain large amounts of this DNA (8).

6. State one reason why scientists formerly thought of repetitive DNA as “junk.” [1]

7. Write the number of the sentence that provides evidence supporting the hypothesis that increasing amounts of repetitive DNA are responsible for increased sizes of organisms. [1]
 

Questions on Standard 1, Key Idea 1—Purpose of Scientific Inquiry: Answers and Explanations


1. Key Idea 1—Purpose of Scientific Inquiry
One response is required. Acceptable responses include:
Kills bacteria
Produces vitamin D
Treats diseases and/or wounds

One response is required. Acceptable responses include:
The “tanning myth” involves people believing that a tan is a sign of good health.
The “tanning myth” says that a good tan is good for people.
 

3 The production of melanin, which causes tanning, increases when skin cells are exposed to the Sun is the correct statement concerning tanning. Melanin is a dark pigment that is produced in specialized skin cells in response to ultraviolet radiation in sunlight or an artificial source. This information is found in the third paragraph of the passage.
 

WRONG CHOICES EXPLAINED:
(1) Tanning causes a decrease in the ability of the skin to regulate body temperature is not a correct statement concerning tanning. There is no known relationship between tanning and body temperature regulation.
(2) Radiation from the Sun is the only radiation that causes tanning is not a correct statement concerning tanning. Tanning can also occur when the skin is exposed to artificial sources of ultraviolet radiation. A reference is made in the fourth paragraph of the passage to “tanning parlors” where people can be exposed to artificial doses of ultraviolet radiation.
(4) Melanocytes decrease their activity as exposure to the Sun increases, causing a protective coloration on the skin is not a correct statement concerning tanning. Melanin is produced as a protective pigment that helps prevent deep penetration of ultraviolet radiation into the deep layers of the skin. When ultraviolet radiation is absorbed by melanocytes, their activity increases, not decreases.
2  It stimulates the skin to produce antibodies is not a correct statement concerning ultraviolet radiation. There is no information in the passage relating to the production of antibodies as a result of absorption of ultraviolet radiation, and no known research indicates this type of relationship.
 

WRONG CHOICES EXPLAINED:
(1), (3), (4) It may damage the skin, it is absorbed by the skin, and it may stimulate the skin to produce excess pigment are all correct statements concerning ultraviolet radiation. Ultraviolet radiation is an invisible but extremely powerful form of electromagnetic radiation. It can penetrate unshielded living tissues and alter the genetic makeup of the cells it encounters. In humans, this radiation can cause the production of melanin from melanocytes; in extreme cases, it can stimulate the growth of skin cancer.
 

3 The body of knowledge described in this question is an example of a theory. When scientists begin to study a phenomenon in nature, their first step is normally to investigate it through repeated observation and experimentation. As a result of the analysis of the large quantity of data gathered during this process, the scientists then formulate a theory (“well-accepted body of knowledge”) that describes the phenomenon in a way that is consistent with the data.
 

WRONG CHOICES EXPLAINED:
(1) A hypothesis is not the body of knowledge described in this question. Scientists develop a hypothesis (“educated guess”) around their preliminary observations concerning a natural phenomenon. The hypothesis may be proven accurate or inaccurate as a result of the experimentation used to test it. For this reason, a hypothesis cannot be considered a “well-accepted body of knowledge.”

(2) A controlled experiment is not the body of knowledge described in this question. A controlled experiment is a scientific method used to test an experimental hypothesis. The data that results from a controlled experiment can be used to support the development of a “well-accepted body of knowledge,” but it does not constitute that body of knowledge.

(4) A research plan is not the body of knowledge described in this question. A research plan may be a series of controlled experiments designed to test various aspects of a natural phenomenon. The data that results from the research plan can be used to support the development of a “well-accepted body of knowledge,” but it does not constitute that body of knowledge.
 

2 All scientific theories are subject to change and improvement is the statement best illustrated by the information given. Both Lamarck and Darwin developed their theories of evolution based on observations made and inferences drawn before there was a good understanding of the genetic basis of variation. Lamarck’s earlier theory of “use and disuse” was disproven by later experiments of other scientists. Darwin’s later theory of “natural selection,” though much closer to the currently accepted scientific theory of evolution, has been modified and improved on by the work of later scientists who have had the benefit of modern-day research in genetics, paleontology, and other sciences.
 

WRONG CHOICES EXPLAINED:
(1) Scientific theories that have been changed are the only ones supported by scientists is not the statement best illustrated by the information given. Scientists generally support theories that have stood the test of good scientific research. A theory that has not changed, as long as it is still supported by such research, is generally supported by most scientists.
(3) Most scientific theories are the outcome of a single hypothesis is not the statement best illustrated by the information given. In fact, scientific theories are based on the results of many experiments that each contain their own independent hypotheses.
(4) Scientific theories are not subject to change is not the statement best illustrated by the information given. Scientists are constantly questioning and reevaluating scientific theories. It is likely that a vast majority of all scientific theories undergo at least some modification.
One response is required that indicates a reason why scientists formerly thought of repetitive DNA as “junk.” Acceptable responses include: [1]
Scientists did not understand the function of repetitive DNA.
They didn’t know what it did, and so they thought it was junk.

One credit is allowed for indicating that either sentence 6 or sentence 7 provides evidence supporting the hypothesis that increased amounts of repetitive DNA are responsible for increased sizes of organisms. These sentences give information about the results of scientific investigations that measured the amount of repetitive DNA in the cells of giant pumpkins and miniature pumpkins and found that giant pumpkins contain more of this kind of DNA than miniature pumpkins.