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Purpose of the Bulletin
The purpose of these bulletins is to provide students and
teachers with information about the diploma examinations
scheduled for the 1999-2000 school year.
Please share the contents of these bulletins, particularly the
sample questions, writing assignments, and the scoring criteria,
with your students.
These bulletins include
• descriptions of diploma examinations that will be
administered in November 1999, and in January, April, June,
and August of 2000
• the blueprints for the examinations
• the scoring criteria for the 1999-2000 school year
• suggestions for students about writing the examinations
• descriptions of the standards for the courses and
examinations
• examples of students’ responses for Mathematics 30,
Mathematics 33, Science 30, Biology 30, Chemistry 30,
Physics 30. (Examples of students’ responses for humanities
examinations are on the extranet.)
1
Information for Markers/T eachers
Scoring and Marking of the Examinations
Scoring and marking of the examinations takes place shortly after
each administration date.
All writing assignments and extended-response assignments are
scored by teachers selected from among those who have been
recommended as markers by their superintendents to the Student
Evaluation Branch.
In early September, the Student Evaluation Branch sends
superintendents a letter requesting the names of recommended
markers. Dates for scoring the examinations are armounced in this
letter.
Student Evaluation Branch staff contacts recommended markers
before each marking session to confirm their participation, as well as
the dates and times for marking.
Qualifications To qualify for recommendation by a superintendent, a teacher must
have taught the diploma examination course for two or more years,
be teaching the course in the current school year, hold an Alberta
Permanent Professional Teaching Certificate and be employed by a
school authority in Alberta.
Dates for Recommendation Teachers who wish to be recommended as markers for the
January or June diploma examinations should contact their
superintendent by the dates given below. A teacher should
clearly indicate to the superintendent which examination he or
she wishes to mark.
Administration Contact Superintendent by
January, 2000 October 1, 1999
June and August, 2000 Mareh 1, 2000
Markers for the November examinations will be seleeted from the
list submitted by superintendents for the previous June marking
session; markers for the April examinations will be selected from the
list for the previous January marking session.
2
Criteria for Selection
In most subjects, more teachers are recommended as markers by
superintendents than are required by the Student Evaluation Branch
for any one marking session. The following criteria are used when
markers are selected for a particular marking session:
• experience as a marker (in some subjects, qualified first-time
markers will be selected first; all selection will be done to balance
numbers of new and experienced markers.)
• regional representation
• proportional representation by student population
Please note: teachers may mark only one subject in a marking
session. No teacher may mark both a diploma examination and an
achievement test in July.
Examination Development
As the need arises for teachers to participate in item writing and
field testing, letters are sent to superintendents requesting their
nominations. Item writing takes place throughout the year and is a
vital component of the diploma examination program. Field testing
provides important validation of questions. It also provides students
and teachers with the opportunity to become familiar with the nature
of questions they will encounter on future diploma examinations.
Only teachers who have been nominated by their superintendents are
eligible to participate in these activities. Teachers who are
interested in these activities should contact their superintendents.
Inservices and Presentations
If you are seeking information about or wish to book a workshop
related to diploma examinations, interpretation of examination
results, and other examination-related issues, contact your
Professional Development Consortia. You may also contact either
Elana Scraba, Assistant Director Humanities, or Corinne McCabe,
Assistant Director Mathematics/Science, at the Student Evaluation
Branch at 780-427-0010 for information and to book speakers.
3
Other Important Documents
Student Evaluation produces many important documents that people
who are seeking information about diploma examinations will find
helpful. All of these documents are posted either on the Alberta
Learning site (http;//ednet. edc.gov.ab.ca) or on the secured Alberta
Learning extranet.
• Students First: A Guide for Students Preparing to Write a
Diploma Examination — A Students First guide is produced for
each diploma examination subject. These publications contain
valuable information and suggestions for students about
examination preparation and examination writing. We recommend
that students and teachers examine these documents early in the
term to prepare for the diploma examinations
• General Information Bulletin, Diploma Examinations Program
(1999-2000) — Each September, the Student Evaluation Branch
sends all superintendents and senior high school principals copies
of the General Information Bulletin, Diploma Examinations
Program. This bulletin provides the information, dates, policies,
and rules that apply to the administration of all diploma
examinations for the school year. It also provides information
about partial writings, the use of word processors, the use of
calculators, accommodations for students with learning and/or
physical disabilities, dates for examination administration, and
definitions of mature students, among other things.
• Examples of Students ’ Writing — Samples of student writing from
the January 1999 examination administration of English 30,
English 33, Social Studies 3 3, and Social Studies 30 are posted on
the Alberta Learning extranet. These examples represent the
standards set for the marking of the examination. Teachers are
able to access this secured web site through their school’s
identification number.
• Examiners ’ Report — Following the administration of January and
June diploma examinations, the Student Evaluation Branch
produces an Examiners ’ Report for each diploma examination.
These documents are sent to all senior high schools in Alberta, and
are posted on Alberta Education’s extranet site.
Each Examiner ’s Report contains
- detailed provincial results
- examiners’ comments about student performance on the
examination
- a blueprint of the examination by reporting category
- the key and difficult level for all questions on the examinations
- sample questions accompanied by commentary
4
UNIVERSITY LIBRARY
Each Examiners ’ Report provides important information for
teachers who wish to interpret their students’ results in
relationship to provincial results as an ongoing form of program
evaluation.
School and Jurisdiction Reports — These reports are made
available electronically on the extranet to schools and school
jurisdictions after each January and June administration. The
School and Jurisdiction Reports provide detailed information on
how well students in the school and school district, respectively,
did on each of the diploma examinations relative to provincial
standards. Teachers may use these data to reflect on areas of the
program where their students did well and on areas where student
performance could be improved.
Annual Report, Diploma Examinations Program — This report
contains information about the results achieved by all students
who wrote diploma examinations in the preceding school year. It
also contains the results of any special study related to the diploma
examinations.
Diploma Examinations Program
Year
Special Studies Topic
1989-90
Comparing Achievement in Various Diploma Examination
Courses
1990-91
Different Paths to Success in Diploma Examination
Courses
1991-92
Participation Rates in Diploma Examinations Courses
1992-93
Conventions of Language
1993-94
Participation Rates Over Time
1994-95
Grade 12 Enrollment Decline — ^A Preliminary Assessment
1995-96
Differential Item Performance Between Males and Females
on the June 1996 Administration of the Social Studies 30
Diploma Examination
1996-97
Achievement-Over-Time for English 30 and
Social Studies 30 Diploma Examinations
1997-98
Special Study: Achievement-Over-Time for the Multiple-
Choice Section of the English 30 and Social Studies 30
Examinations, 1989-1998
1997-98
Special Study: Achievement-Over-Time for the Biology 30
Extended Written-Response Question (June 1995 and June
1998 Comparison)
The 1996-97 and 1997-98 annual reports are available on the
Internet at the Alberta Learning web site.
5
• Previous Examinations: Copies of previous Mathematics 30,
Mathematics 33, Science 30, Physics 30, Chemistry 30, and
Biology 30 diplomas examinations and keys are posted on the
Alberta Learning web site. English 30, English 33, Social Studies
30, Social Studies 33, and Fran9ais 30 examinations are not
available on the web site because of copyright restrictions for
electronic publication of the source materials on these
examinations. However, keys for the multiple-choice parts of all
humanities examinations are posted.
You may purchase copies of the diploma examinations from the
Learning Resource Distributing Centre (LRDC)
by phone: (780) 427-5775 (toll-free 310-0000)
by fax: (780)422-9750
on the web: www.lrdc.edc.gov.ab.ca
by mail: 12360-142 Street, Edmonton, AB T5L 4X9
6
Contents
Page 1
Objectives of the Course
Page 1
Standards
Page 2
Examination Specifications
Page 4
Examination Design
Page 5
Assessment of STS Connections
Page 5
Assessment of Communication Skills
NEW
Page 6
Archived Information from Previous Bulletins
NEW
Page 6
Internet Sites Recommended for Alberta Students
and Teachers
Page 8
Written-Response Questions
Sample Closed-Response Question and Scoring Guide
Sample Open-Response Question, Suggested Responses,
Scoring Guides, and Student Responses and Rationales
Page 28
General Comments About the New Open-Response
Scoring Guide
NEW
Page 29
Hardy-Weinberg Calculations
NEW
Page 30
Implementation of the New Open-Response
Scoring Guide
Digitized by the Internet Archive
in 2016
https://archive.org/details/diplomaexaminat999albe_11
Objectives of the Course
Standards
Acceptable Standard
Biology 30 is intended for students who want to better understand
the biology prineiples behind the natural events they experience and
the technology they use in their daily lives. Biology 30 is an
experimental discipline requiring creativity and imagination. It
develops the knowledge, skills, and attitudes to help students
become capable of and committed to setting goals, making informed
choices, and acting in ways that will improve their own lives and life
in their communities.
Students of Biology 30 have developed their aptitude for observing,
collecting facts, forming generalizations, hypothesizing, and making
inferences from observations. They have shown growth in their
understanding of biological concepts by their increased ability to
apply these concepts to relevant situations. They have learned to
communicate in the specialized language of biology.
This growth and development in students has taken place as a result
of general education and cognitive maturation. It has been enhanced
by science courses, in particular by the successful completion of
Science 10 and Biology 20. These courses develop knowledge and
skills that are prerequisite to success in Biology 30.
Students who attain the acceptable standard but not the standard of
excellence in Biology 30 will receive a final course mark between
and including 50% and 79%. These students can demonstrate a
basic understanding of the nature of scientific inquiry by designing,
observing, and interpreting simple laboratory and field
investigations. They can readily interpret physiological, genetic, and
ecological data that are presented in simple diagrams, tables, and
graphs. They can translate word descriptions of biological processes
into symbolic representations that facilitate solving simple
quantitative genetic and ecological problems. These students can
demonstrate understanding of equilibrium by describing how the
human nervous and endocrine systems regulate other body processes
such as reproduction. They can show how environmental and
genetic factors regulate change in the development of organisms.
They can describe how cellular and molecular processes cause
diversity in organisms. They can illustrate how populations interact
with each other, thereby forming communities that over time are in
equilibrium or in a state of change. These students recognize and
understand key biological and technological terms and therefore can
interpret short reports of current biological issues. They can identify
the scientific, technological, and societal components of biological
problems and explain how these components interrelate in solutions.
1
These students can compose clear and logical descriptive or
explanatory statements about major biological issues.
Standard of Excellence Students who achieve the standard of excellence in Biology 30
receive a final mark of 80% or higher. In addition to meeting the
expectations for the acceptable standard of performance, these
students demonstrate their aptitude and interest in biology and feel
confident about their abilities. They can readily interpret
interrelated sets of data such as complex graphs and tables. They
can analyze and evaluate experimental designs. These students can
provide explanations of concepts that are specific but also
comprehensive. They can simultaneously apply two or more
biological concepts that cross major themes. They can demonstrate
a thorough understanding of quantitative relationships and solve
multistep numerical problems. When presenting scientific data, they
select the most appropriate form. They can analyze complex open-
ended issues that are of a new or unique nature. The contexts of
these issues would most likely include current research. These
students are aware of a variety of viewpoints relating to
environmental and ethical issues in the field of science and
technology. They can communicate clearly and concisely, using
appropriate scientific vocabulary, and can write compositions.
Achievement Standards At a provincial level it is expected that at least 85% of students will
achieve a final course mark of 50% or higher. It is also expected
that at a provincial level, at least 15% of students will achieve a final
course mark of 85% or higher.
Examination Specifications
Each Biology 30 diploma examination is designed to reflect the
Biology 30 course general learner expectations outlined in the
Biology 20-30 Program of Studies, June 30, Interim 1995, for
Senior High Schools. The general learner expectations are
expressed in more detail by the specific learner expectations, which
are organized into four units. Some questions on each diploma
examination will assess achievement of specific learner
expectations. Some questions will be based on the integration of
several specific learner expectations.
All examination questions are organized into sets that relate to broad
contexts. Therefore, a set of questions may assess students’ ability
to integrate several general learner expectations (GLEs). All
questions will measure achievement of scientific knowledge; some
will also measure achievement of skills and/or STS connections.
2
The 1999-2000 Biology 30 diploma examinations are constructed to place the following approximate emphases
on the Biology 30 course general learner expectations.
Knowledge
Emphasis
The student can demonstrate that
• humans use nervous and
endocrine systems to maintain
internal equilibrium among their
systems while simultaneously
interacting and maintaining
equilibrium with the external
environment
20-25%
• humans and other organisms have
chemically regulated reproductive
systems, which ensure survival of
the species, and can describe how
sexually transmitted diseases
interfere with human reproductive
function
10-15%
• cell differentiation and organism
development are regulated by
genetic and environmental factors
and that natural processes can be
changed by using reproductive
technologies
5-10%
• cell division in vascular plants and
animals promotes growth, genetic
continuity, and diversity of
organisms; and that genetic traits
are inherited and expressed in
predictable ways if chromosome
segregation, assortment, and
crossing over are taken into
account
25-30%
• genetic information stored in
DNA molecules directs the
functions of organisms and that
biotechnology can be used to
influence genetic expression
10-15%
• gene frequencies within
populations determine the
composition of communities and
that these gene frequencies may
reach equilibrium or continue to
change over time as populations
interact
15-20%
Scientific Process and Emphasis
Communication Skills 20-30%
The student can
• design, interpret, explain, analyze, and evaluate
investigations
• organize data into tables, graphs, and diagrams
and predict relationships
• interpret, explain, analyze, and evaluate data to
infer relationships
• use appropriate scientific terminology and
mathematical language to communicate and
explain scientific concepts
Science, Technology, and Society Emphasis
Connections (STS) 20-30%
The student can
• apply cause-and-effect reasoning to formulate
relationships in which scientific evidence shapes
or refutes a theory, and explain the limitations of
science and technology in answering all
questions and solving all problems
• describe and evaluate the design and function of
technological solutions to practical problems by
using scientific principles and theories, and
relate the ways in which science and technology
advance one another
• evaluate from a variety of perspectives how
science and technology are influenced and
supported by society, and assess the ability of
society to interact responsibly with the
environment
• apply the skills and knowledge acquired in
Biology 30 to everyday life and to related and
new concepts in post-secondary studies of
biology
3
The design of the 1999-2000 Biology 30 diploma examinations is as
follows:
Question
Format
Multiple Choice
Numerical Response
Written Response
Number of Percent
Questions Emphasis
48
8
2
60
10
30
The machine-scored portion of each examination contains both
multiple-choice and numerical-response questions, some of which
may be grouped together in sets that relate to specific contexts.
Answers for multiple-choice questions are recorded in the first
section of the machine-scored answer sheet, and answers for
numerical-response questions are recorded in the second section on
the same side of the machine-scored answer sheet. Answers to the
written-response questions are written in the examination booklet.
Multiple-choice questions are of two types: discrete and context
dependent. A discrete question stands on its own without any
additional directions or information. It may take the form of a
question or an incomplete statement. A context-dependent question
provides information separate from the question stem. Most of the
multiple-choice questions are context dependent.
Numerical-response questions are of three types: calculation of
numerical values; selection of numbered events, structures, or
functions from a list; and determination of a sequence of events.
Specific instructions for recording answers for each type of
numerical-response question are provided in the instruction pages of
each Biology 30 diploma examination and with each question. It
should be noted that the correct answer for any one question will not
necessarily require use of all four columns in the grid provided on
the answer sheet.
A particular context may be used for one or more multiple-choice
questions and/or one or more numerical-response questions.
The written-response portion of each Biology 30 diploma
examination contains two contextual questions: a closed-response
question and an open-response question. Each question has a value
The closed-response question (Written-Response 1) presents a
synopsis of research. Pertinent data are provided in the form of
graphs and/or tables. The several parts of this question may require
students to demonstrate a variety of science process skills.
of 15%.
The open-response question also presents a problem based on
current research. It requires students to make connections among
biological concepts, technology, and/or social issues. The response
to this question is expected to have complete sentences and
paragraphs, and be presented as an expository composition. In an
expository composition, a student can be expected to explain,
describe or provide an argument.
For the open-response question (Written Response 2), students are
given a writing space consisting of three blank pages alternating
with three lined pages. This writing space will be the same for eveiy
Biology diploma examination. In addition, blank perforated pages
are provided at the back of every science diploma examination.
Assessment of STS Connections
Examination questions measure the students’ understanding of
biological concepts. Some questions also measure the students’
development of the skills and thinking processes associated with
scientific inquiry, and some questions have been designed to
measure students’ understanding of the interrelationships between
science and technology and among science, technology, and society.
Assessment of Communication Skills
Communication skills are assessed most directly in the marker-
scored questions. For the open-response question, the descriptions
used in the scoring guides may include criteria for assessing
communication skills along with criteria for the other components.
The term communication skills includes those processes by which
understandings are expressed using appropriate conventions. These
conventions include:
• words, sentences, paragraphs
• graphs, diagrams
• mathematical formulas, mathematical and chemical equations
• significant digits, units of measurement
Conventions that are considered appropriate for a particular response
are subject- and question-specific.
5
Archived Information from Previous Bulletins
NEW Each bulletin contains unique information of value to teachers,
especially teachers new to the program. Information such as course
clarifications, reminders and explanations, and definitions of terms
that are relevant to the diploma examination program can be found
in the Archived Information section of specific subject bulletins on
the website. Only information that is applicable to current diploma
examination programs has been archived.
Year Topic
1998-99 Development of the New Open-Response Scoring
Guide.
1997-98 Science and Technology (Descriptions of various
genetic technologies and their uses)
Science, Technology, and Society
Issues in Science, Technology, and Society
Relationships Among Organisms of Different
Species
1996-97 Pedigree Analysis
Chromosome Formation
Counting Chromosomes
Succession
Graphing
1995-96 Chromosome Number Descriptions
Genetic Conventions
Internet Sites Recommended for Alberta Students and Teachers
NEW The following list of Internet sites can be used as resources by
both students and teachers of Biology 30. When accessing
electronic information, it is important to evaluate the authority,
reliability, and validity of the information and to identify and
analyze factors that affect the authenticity of the information.
• Access Excellence®: A Place in Cyberspace for Biology
Teaching and Learning
http://www.accessexcellence.org/
The site includes links to What ’s News in biology-related
research, issues and ethics in biotechnology, a biology
activities exchange, and a sampling of online collaborative
projects.
6
• The Center for Molecular Neuroscience: Online Journal
Links
http://www.mc.vanderbilt.edu/brainscience/iQumlinks.html
A Vanderbilt University School of Medicine site that
includes links to many recognized science journals related to
the human nervous system such as the Journal of Molecular
Neuroscience, Behavioral and Brain Sciences, On the Brain,
and the Scientific American Journal.
• The Virtual Embryo
http://www.acs.ucalgarv.ca/~browder/
A University of Calgary site that includes visual images of
developing embryos of a number of different species, current
developmental biology research, and links to related learning
resources.
• The Multi-Dimensional Human Embryo
http://embrvo.mc.duke.edu/
A collection of magnetic resonance images of developing
human embryos.
• National Center for Biotechnology Information
http://www3.ncbi.nlm.nih.gov/
A site that includes several links related to Mendelian and
molecular genetics such as the Human Genome Project,
genes and disease, and The Online Mendelian Inheritance in
Man.
• Links to Human Disease Related Pages
http://wsrv.clas.virginia.edu/~rih9u/disease.html
A site that includes several links related to human disease
such as cystic fibrosis. Mad Cow Disease, Thalassemia,
hemophilia, Down syndrome, Turner syndrome, Klinefelter
syndrome, and others.
• Canadian Wildlife Service
http://www.cws-scf.ec.gc.ca/cwshom e.html
A site featuring Canadian species’ population information
including links to current population research and
government publications related to populations.
7
Written-Response Questions
Each Biology 30 Diploma Examination has two written-response
questions. One of these is a closed-response question that is
presented in parts. The number of parts is dependent upon the
context. Each part is scored using a closed-response scoring guide.
The parts of this question total to a score of 12 worth 15% of the
examination. All of the parts of this question are scored by one
teacher.
NEW The other written-response question is an open-response question
that requires an expository composition. In an expository
composition, a student is expected to explain or describe something,
or to provide an argument. Beginning in January 1999, the open-
response question on Biology 30 examinations will be scored using
two six-point scoring scales, each with a range of 0 to 5. The
“Science” scale assesses a student’s response on the science aspects
of the question. The “Technology and Society” scale assesses a
student’s response on these aspects of the question. Each bullet on
the scoring guides describes a part of the student’s response at the 5,
4, 3, 2, or 1 level. These descriptions are used to award a mark out
of 5 for the part of the question that the bullet describes. The
average of these marks is then used to determine the overall score
for each of the two scales. The “Science content” mark is weighted
to be worth twice as much as the “Technology and Society” mark.
Each student’s response will be scored independently by two
markers. The two Science content scores will be added together for
a combined sub-score out of ten. The two Technology and Society
scores will be added together and then divided by two for a
combined sub-score out of five. The two sub-scores will be added
together for a total out of 1 5. The open-response question is worth
15% of the biology examination.
A summary of the calculations follows:
Science scale: Marker 1 Score (X out of 5) + Marker 2 Score (Y out
of 5) = Sub-score (X + Y out of 10)
Technology and Society scale: Marker 1 Score (X out of 5) +
Marker 2 Score (Y out of 5) divided by 2 = Sub-score out of 5
Final Score = Science (out of 10) + Technology and Society
(out of 5) = maximum of 15 marks
If the final scores obtained by the two independent markers vary by
8 or more, out of 15, the scores are classified as discrepant.
Responses that have discrepant scores are read by a third reader.
The third reader must assign a score that is equal to one of the scores
of the first two readers or is between these scores.
8
A summary of the calculations for a discrepant paper follows.
Science:
Marker 1 assigned a score of 5 out of 5 marks
Marker 2 assigned a score of 2 out of 5 marks
Technology and Society:
Marker 1 assigned a score of 4 out of 5 marks
Marker 2 assigned a score of 2 out of 5 marks
If Marker 1 were the only marker, the student’s score would have
been 14 out of 15. If Marker 2 were the only marker, the student’s
score would have been 6 out of 1 5 . This represents a difference of 8
and is a discrepant score.
Third Marker:
Reader 3 must assign a score of 2, 3, 4, or 5 on the Science scale
and a score of 2, 3, or 4 on the Technology and Society scale.
The third reader’s Science score will be doubled for a total out
of ten and added to his or her Technology and Society score for
a total score out of 15.
For an example of an open-response question, suggested responses,
scoring guides, and sample student responses with scores and
rationales, see pages 14 to 28. Students should be made aware of
the change in scoring systems for the open-response question.
9
Sample Closed-Response Question and Scoring Guide
The following question is taken from the April 1997 Biology 30 Diploma Examination.
Use the following information to answer the next question.
In April 1994, a medical team from the University of Pennsylvania used gene therapy to
treat a 28-year-old Canadian with familial hypercholesterolemia. This rare genetic
disease had resulted in her having a heart attack at age 16 and a coronary bypass at age
26. Two of her brothers had died in their twenties of heart disease.
The disease causes extremely high cholesterol levels and is the result of a mutation in
the gene that codes for the LDL-receptor protein. This LDL-receptor protein, found on
the cell membrane of liver cells, removes low-density lipoproteins (LDLs) from the
bloodstream. LDLs are the “bad” cholesterol molecules associated with clogged arteries
and heart attacks. Normal cholesterol-reducing drugs did not work for this woman
because her LDL-receptors were defective.
The geneticists, James Wilson and Mariann Grossman, used gene therapy to add normal
genes to code for the LDL-receptor protein she needed. The defective genes she already
possessed were not “shut off,” but gene therapy would allow more normal LDL-
receptors to be produced so the symptoms of the disease would be reduced.
Gene therapy methods to treat hypercholesterolemia use non-infectious viruses that have
been “cleaned of all their harmfiil genes” and modified by having a normal copy of the
human LDL-receptor gene inserted. Two methods exist; each uses a different type of
virus. The retrovirus is a RNA-containing virus that converts its RNA into DNA by
means of the enzyme reverse transcriptase. Once converted, the viral DNA is then
integrated into the host cells’ chromosomes. The adenovirus is a DNA-containing virus.
Adenovirus DNA only temporarily integrates itself into the host cells’ chromosomes.
Retrovirus Method Adenovirus Method
(used in this treatment) (used only on mice)
Retroviruses were modified* to contain
the normal LDL-receptor protein gene.
The team surgically removed 15% of the
woman’s liver. In the lab, the modified
retroviruses were released into liver cells.
Transcription occurred and LDL-receptor
proteins were then synthesized.
The treated liver cells were allowed to
divide and increase in number for 3 days.
These liver cells were returned to the
woman’s liver.
The altered cells colonized the liver tissue
and began removing LDL cholesterol.
The woman’s LDL levels dropped by
1 7%, and she began responding to
cholesterol-reducing drugs.
*Diagrammatic example of how modification may take place in both methods:
Viral DNA
Human DNA
Adenoviruses are modified* to contain
the normal LDL-receptor protein gene.
Adenoviruses are injected into the
bloodstream and become attached to
liver cells. Adenovirus DNA is released
into liver cells. Transcription occurs and
LDL-receptor proteins are then
synthesized.
More adenovirus must be added at three-
week intervals in mice.
10
I 1. I a. Describe the difference between an adenovirus and a retrovirus.
(1 mark)
Structural difference: An adenovirus has DNA as its genetic
material; whereas, a retrovirus has RNA as its genetic material
or
Functional difference: Adenovirus DNA only temporarily
integrates itself into host cell chromosomes; whereas, converted
retrovirus DNA integrates itself for the cell’s lifetime.
b. Explain one advantage and one disadvantage of each method.
(2 marks)
Retrovirus Method
Adenovirus Method
Advantages
Advantages
• Continuous production of the
LDL-receptor protein
• Has been used in humans
• Retrovirus DNA integration is
permanent
• Close monitoring of the
effectiveness of treatment is
possible
• Surgery is not required and
treatment is simple
Disadvantages
Disadvantages
• Surgery involves risks
• Treatment has complex
components that increase risks
• Treatment must be repeated at
regular intervals, therefore the
treatment is temporary.
• Adenovirus DNA does not
integrate permanently into its
host ’s DNA
• Has been used only in mice
• Treatment is indirect and
therefore not easily monitored
for effectiveness
c. i. If homozygous individuals with mutant alleles were to be
considered for gene therapy, at which stage of human
development, from conception onward, would treatment be
most effective? (1 mark)
The zygote, blastocyst, or pre-embryo (early embryo)
11
ii. Support your answer. (1 mark)
Gene therapy at this time allows all or most cells to possess the
working versions of the gene.
One mark can be earned for support even though a mark was
not earned for correctly answering c. i.
iii. Describe a technology that would be needed to accomplish the
modification as described in the diagram. (2 marks)
Technology
Description
Restriction enzyme
An enzyme that cuts DNA at specific sites;
used to cut open vector (viral) DNA and to
cut genes out of human DNA
Ligase
An enzyme that seals together cut ends of
DNA; used to seal the human gene into the
vector (viral) DNA
Cloning
A procedure that involves the use of
bacteria or enzymes to copy a DNA
segment (gene) many times; used to
provide workable amounts of DNA in the
laboratory
Procedures for identifying, sequencing,
and/or synthesizing the human DNA.
Enzymes and other methods would be used
to identify the gene and sequence it. The
gene may be synthesized using a machine.
Any other description of an applicable technology that the
student links to the diagram is acceptable.
d. This woman likely had inherited two mutant alleles for this
condition. She developed coronary heart disease earlier and more
severely than individuals who inherit only one mutant allele.
i. Predict the mode of inheritance for hypercholesterolemia.
(1 mark)
Codominance or partial dominance or incomplete penetrance
or incomplete dominance or intermediate inheritance
ii. Explain why this mode of inheritance can result in early and
late onset of coronary heart disease. (2 marks)
Late onset occurs in heterozygous individuals because one copy
of the normal gene is present; therefore, some ability to remove
“bad” cholesterol would likely delay the onset of symptoms.
Early onset occurs in homozygous individuals because they do
not produce any normal LDL-receptor proteins. There is no
12
way of removing “bad” cholesterol from the bloodstream;
therefore, clogged arteries and heart attacks will likely occur.
or
Both alleles have an effect on the phenotypes of the individual,
(one mark)
e. Gene therapy raises important societal concerns. Describe one
possible societal concern that might arise as a result of the gene
therapy performed on this woman. (2 marks)
Once gene therapy is used to treat disease, it will be used to
replace non-defective genes; for example, inserting genes for blue
eyes or other vain genetic manipulation.
or
If the treatment is expensive, it may not be available to everyone;
therefore, only rich people will be able to afford the treatment.
or
If the treatment is expensive, spending tax money to help one
person or few people may not be justified.
or
Even though the viruses used were “disarmed, ” some people may
disagree with the use of infectious organisms to treat people.
There may be unforeseen consequences because the viruses may
disrupt cell functioning in some way.
or
Gene therapy may result in the alteration of the gene pool by
changing gene frequencies. There may be an unfavourable
alteration of gene frequencies.
or
Some people in society are afraid of the unknown. The concepts of
gene therapy are generally unknown; hence, people may be
skeptical of this type of treatment and protest its use.
or
Some people have extreme views on gene therapy: the
accommodation of extreme views may prove difficult for society or
people holding extreme views may protest, which could disrupt
society.
or
Any other societal concern (e.g, prioritization of treatment).
Note: Societal concerns must apply to the society as a whole. If
some people ’s particular religious beliefs or convictions can
be shown to be important to the society in general, then the
beliefs or convictions can be counted as possible societal
concerns.
13
Sample Open-Response Question, Suggested Responses, Scoring Guides,
and Student Responses and Rationales
Use the following information to answer the next question.
Retinoblastoma
-from W.H. Freeman and Co., 1993 -from American Association for the
Advancement of Science, 1996
The child above has retinoblastoma, a retinal cancer that can be fatal. The tumour is visible
in the image above.
Childhood tumours of the retina are associated with the inactivation of the retinoblastoma
gene. Retinoblastoma is the most common malignant eye tumour of childhood. It occurs in
about 1 in 20 000 live births. The disorder is caused by tumour cells that develop in one or
both eyes in children under five years of age. It is usually diagnosed initially by a bright
white or yellow mass in the pupillary area behind the lens.
There are hereditary and non-hereditary forms of retinoblastoma. In hereditary
retinoblastoma, there is a germ cell mutation that predisposes the individual to the
development of the retinal tumour.
Retinoblastoma is almost uniformly fatal if not treated in its early stages. Cancer tumour cells
can quickly spread throughout the body to form new tumours, a process called metastasis.
However, with early diagnosis and modern methods of treatment, the survival rate is over
90% for people with retinoblastoma.
The gene responsible for the hereditary cases of retinoblastoma is found on chromosome 1 3
and is believed to belong to a class of human cancer genes that are regulatory in function.
Retinoblastoma results when a retinal cell of an individual has two inactivated versions of the
gene. However, inheriting only one copy of the mutated gene increases the risk of
developing the disease. The second mutated gene necessary to display the phenotype arises
by random mutation (30%) or by abnormal crossing over during mitosis (70%). The normal
protein for which the gene codes plays a role in the control of the cell cycle. In the absence of
the normal protein, a cell will continue into the next cell division without an opportunity to
become quiescent. This uncontrolled division leads to cancer.
I 2. I Write an expository composition on how retinoblastoma affects a person,
develops, and is diagnosed, and explain and how its incidence can be
reduced in a population.
• Explain how retinoblastoma could interfere with the normal processes
involved in sight. Provide the necessary details of the physiology of
the eye and brain.
• Diagram the phases of the cell cycle and explain how the cell cycle
would be affected in cells of an individual homozygous for the
inactivated regulatory gene associated with retinoblastoma.
14
• Explain genetic counselling, constructing example crosses to aid in
your explanation, or explain genetic screening. Explain how the
information gathered by either genetic counselling or genetic screening
could be used to help reduce the incidence of retinoblastoma in the
population.
Illustration Credits
Photograph on left from An Introduction to Genetic Analysis (W.H. Freeman and
Company, 1993). Reprinted by permission of Custom Medical Stock Photo, Inc.
Photograph on right reprinted with permission from
http;//www.ncbinlm.nih.gov/cgi-bin/SCIENCE96/gene? RBI. Copyright 1996
American Association for the Advancement of Science. Readers may view,
browse, and/or download this material for temporary copying purposes only,
provided these uses are for non-commercial personal purposes. Except as
provided by law, this material may not be further reproduced, distributed,
transmitted, modified, adapted, performed, displayed, published, or sold in
whole or in part, without prior written permission from AAAS.
Suggested Responses
Interference with Normal Vision
The tumour develops in and among the retinal cells of the eye. The retina
normally changes light stimuli into electrical impulses. The optic nerve then
transmits these impulses to the occipital lobe of the cerebrum, which interprets
the impulses to produce sight. The tumour therefore results in blindness.
or
A diagram could also be used to show disruption of vision by the tumour and of
the function of the parts involved.
or
Some students may identify damage to the vitreous humour, optic nerve, and/or
choroid coat, as well as to the retina. (These are reasonable hypotheses based
on the photograph of the eye showing the tumour location.) The tumour
obstructs the normal function of these parts by interfering with focussing, neural
transmission, and/or light refraction, respectively.
Phases of the Cell Cycle and Disruption by the Abnormal Gene
The cell cycle diagram should be complete and should show a relatively long
interphase. (Interphase may be divided into Gj, S, and G2 phases, but this is not
necessary.)
15
An individual who is homozygous for the inactivated cell control gene will not
produce a normal protein for this function. The cell will not enter interphase or
will have a shorter interphase because of the missing regulatory or control
protein. This will result in more cell reproduction than normal, which results in
a tumour. Normally, retinal cells only divide during growth of a tissue and when
replacing damaged cells. During interphase, cells carry on their normal cell
functions.
Genetic Counselling
The abnormal allele for control of cell division in the retinal cells is recessive.
This means two copies are necessary to display the phenotype and develop the
cancer tumour. However, since the second recessive allele usually arises in the
individual because of a mutation or abnormal mitosis, only one copy of the
abnormal allele is necessary for increased risk of developing retinoblastoma.
Crosses
If an individual has retinoblastoma, he or she may be genotypically homozygous
for the abnormal allele or only some of the retinal cells may be homozygous for
the allele and the rest of their cells may be heterozygous. (A heterozygous
individual can develop a second mutated allele in their retinal cells. The
heterozygous state is a risk factor.) If the individual marries an unaffected
individual (without the risk factor), the probability of their children inheriting
the mutated allele is shown by the crosses below.
R - normal allele
r - abnormal allele
16
Heterozygous Parent Homozygous Parent
R
r
R
RR
Rr
R
RR
Rr
r
r
R
Rr
Rr
R
Rr
Rr
In this case, the probability is that
50% of the children will have the
risk factor and be carriers of the
abnormal allele.
In this case, the probability is
that 100% of the children will
have the risk factor and be
carriers of the abnormal
allele.
Note: This is a very unusual type of inheritance. If the students response
indicates a straight recessive inheritance and it is well described, the response
could be assigned a 4. If an understanding of “risk” is demonstrated, the
student could have earned a 5.
OR
Genetic Screening
Genetic screening could be used to determine the genotypes of the parents or of a
fetus. In genetic screening, a biochemical test might be used to determine if the
inactive or active protein coded for by the gene was present in an individual ’s
cells. If both proteins (normal and abnormal) are present, the individual is a
carrier of the risk factor. If only the inactive protein is present, the individual is
homozygous for the disease allele. If only the normal protein is present, the
individual is homozygous for the normal allele, and therefore is not at risk,
or
Complementary DNA probes for the mutant allele DNA code and for the normal
allele DNA code could be mixed with the single strand DNA of a parent or a
fetus. If both types of DNA bind to the individual ’s DNA, the individual is a
carrier for the disease allele. If only the mutant DNA binds, the individual is
homozygous for the disease allele. If only the normal DNA binds, the individual
is free of the disease allele, and therefore is not at risk.
Note: Since genetic screening can be used to determine the fetal genotype, a
well-written answer would not require crosses. If only parental genotypes are
determined by genetic screening, then appropriate crosses should be shown.
Reduction of the Incidence of the Disease
In order to reduce the incidence of retinoblastoma in the population, individuals
affected would have to reduce the number of offspring they had with the abnormal
gene. They could be counselled to consider adoption or to remain childless.
or
Alternatively, a method of identifying the risk gene through amniocentesis and
DNA analysis using markers could be used to identify carrier fetuses that could
then be aborted or treated earlier to reduce the effects of the disease.
or
If a parent is heterozygous, in vitro fertilization could be used and only unaffected
embryos (identified by genetic screening) would be implanted in the uterus.
17
SCIENCE
Score
Scoring Criteria
5
Excellent
• A specific structure (e.g., the retina) is logically linked, using appropriate scientific
vocabulary, to the tumour location, its normal Action, and the disruption of the
structure by the tumour.
• The pathway of conversion of light into electrical impulses that travel through the optic
nerve to the occipital lobe of the cerebrum for interpretation is clearly explained.
• A clear diagram of the cell cycle showing mitosis, cytokenesis, and interphase (or G^,
Sj, G2) is drawn. Interphase is significantly longer than mitosis.
• A logical explanation links the abnormal genes to an abnormal regulatory protein and to
a shortened interphase, which results in a tumour.
4
Proficient
• A specific structure is linked, using some appropriate vocabulary, to the tumour
location, its normal function, and the disruption to it by the tumour.
• The pathway from the sensory structures to the optic nerve to the cerebrum of the brain
is described.
• A clear diagram of the cell cycle showing mitosis, cytokenesis, interphase or mitosis,
and Gj, S, and G2 (divisions of interphase) is drawn.
• An explanation links the abnormal genes/abnormal proteins to a shortened interphase,
which results in a tumour.
3
Satisfactory
• A structure of the eye is named and its function is described. A link to the tumour and
abnormal vision is suggested.
• The function of the cerebrum of the brain in interpreting vision or the function of the
optic nerve in transmitting information to the brain is described.
• A diagram of the cell cycle showing mitosis and interphase is drawn.
• A link between the abnormal gene and a shortened interphase or continuous cell
division is suggested.
2
Limited
• A structure of the eye that is disrupted is identified, or a disruption to the eye is
described.
• The tumour’s role in disrupting the pathway of information to the brain is suggested.
• A diagram of the cell cycle is attempted.
• Abnormal cell division is linked to cancer.
Poor
• Only one of the four bullets is addressed.
INSUFFICIENT is a special category. It is not an indication of quality. It should be assigned to papers that
do not contain a discernible attempt to address the issue presented in the assignment or that are too brief to
assess in this or any other scoring category.
18
TECHNOLOGY AND SOCIETY
Score
Scoring Criteria
5
Excellent
• Genetic counselling is described for individuals of varying genotypes. The concept of risk
is addressed. At least two crosses (with correctly identified allele symbols) that support
the genetic counselling are shown.
OR
A genetic screening technique that addresses the concept of risk for parental genotype
crosses or for fetal genotype results is well described.
• A method for decreasing the incidence of the disease allele is identified, and the way in
which it will reduce the incidence of the disease is explained.
4
Proficient
• Appropriate genetic counselling is described and one supporting cross is shown.
OR
An appropriate genetic screening technique is described.
• A method for decreasing the incidence of the disease allele is identified, and the way in
which it will reduce the incidence of disease is suggested.
3
Satisfactory
• Appropriate genetic counselling is partially described or an appropriate cross is partially
completed.
OR
Appropriate genetic screening is partially described.
• A method for decreasing the incidence of the disease allele is identified.
2
Limited
• A description of genetic counselling is attempted.
OR
One appropriate cross is attempted.
OR
An explanation of genetic screening is attempted.
• A method for decreasing the incidence of the disease allele is suggested.
1
Poor
• Only one of the two bullets is addressed, and it is scored as either Satisfactory or Limited.
: >r 'V- ' ' -?V / "" . '-f:' : , ' ;^;:
y: It is not an indication of quality. It should be assigned to papers that do
1.1 ^ i j ..u i ^ — * — ^1. ™ brief to assess in
' '
not contain a discernible attempt to address the issue presented in the assignment or that are too brief
this or any category.
19
Student Sample 1
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20
Science Content Score - 4
Scoring Guide
Bullet Score Rationale
1 5
This student gives a very good explanation of how
retinoblastoma affects the normal processes involved in
sight.
2 5
He/she makes reference to rods and cones within the retina
and explains that impulses are formed there. The student
then mentions that the impulse is transmitted to the brain
(occipital lobe) by way of the optic nerve. It is logical that
if light cannot stimulate the photoreceptors, a disruption of
vision results.
3 2
For the portion of the question dealing with the cell cycle,
the student has included interphase and the phases of
mitosis. A brief description of what is happening in each of
the phases is given. However, there is no indication of how
much time is spent in interphase as compared with mitosis,
which is an important point. According to the student’s
diagrams, it would appear that more time is spent in mitosis.
The student should indicate that much more time is spent in
interphase (90%) than in mitosis. A cell cycle diagram is
not provided.
4 2
The student fails to make the connection between the
shortened interphase and cancer. The student does mention
that the cells divide more rapidly, which is a characteristic
of cancer. This point can be considered as a link to cancer.
Total =
= 14 14/4 = 3.50 Score = 4
Technology and Society Score - Insufficient
The student did not address the issues of genetic counselling, risk, crosses,
and/or genetic screening. There was no attempt made to explain or suggest
how the information gathered could be used to reduce the incidence of
retinoblastoma in the population.
Final Score
4(2) = 8/10 Science
0/5 Technolosv and Society
8/15 Final Score
Note: If this student had addressed the Technology and Society portion of
the question, he or she would have done much better overall on the
question. It is very important that students do all parts of the question.
21
Student Sample 2
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22
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Science Content Score - 3
Scoring Guide
Bullet Score Rationale
1 5 This student gives a logical explanation as to how
retinoblastoma affects the normal processes involved in
sight. The student mentions three structures associated
with vision: the rods and cones, the optic nerve, and the
occipital lobe.
2 4 The student describes the pathway of conversion of light
into electrical impulses. Rods, cones, the fovea, the optic
nerve, and the occipital lobe are mentioned, but the
explanation is vague.
3 0 A diagram of the cell cycle is not provided.
4 3 The student indicates that because of the retinoblastoma
gene, control over the cell cycle would be lost and a
malignant tumour would result. No link was made to an
abnormal regulatory protein or shortened interphase.
Total = 12 12/4 = 3.00 Mark = 3
Technology and Society Score - 5
Scoring Guide
Bullet Score Rationale
1 4 The student indicates that through genetic counselling, it is
possible to determine the probability of passing on the
disease to offspring. One cross involving two heterozygous
individuals is performed, and the idea of increased risk in
the heterozygous condition is presented.
2 5 A method for decreasing the incidence of the disease allele
based on information gathered is identified (not having
children, treatment). An explanation of how this method
will reduce the incidence of the disease is given.
Total = 9 9/2 = 4.5 Mark = 5
Final Score
3(2) = 6/10 Science
5/5 Technology and Society
11/15 Final Score
Note: This student did an excellent job on the Technology and Society part
of the response. However, the Science section is worth twice the
amount of marks toward the student’s overall mark.
23
Student Sample 3
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24
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Science Content Score - 4
Scoring Guide
Bullet Score Rationale
1 5 This student logically linked specific structures (retina,
rods, cones) to the tumour location, normal fimction, and
disruption made by the tumour.
2 3 The student stated the tumour’s role in disrupting the
pathway of information to the brain. Rods and cones,
sensory nerves, and the brain are used to explain the
disruption. The cerebrum, occipital lobe, and optic nerve
are not identified, nor is the interpretation of vision
addressed.
3 4 The student’s diagram of the cell cycle shows interphase
and mitosis. Interphase represents a larger portion of the
diagram than does mitosis — an important point. The
student incorrectly identifies Ml and M2 (likely meant G1
and G2) as being a part of interphase, but does say that
replication of DNA occurs during the S phase. Cytokinesis
is not mentioned.
4 3 Abnormal cell division is linked to cancer. No link was
made to the abnormal regulatory protein. However, a link
to the gene is suggested when the student indicates that
because mitosis is occurring at a faster rate with a shortened
interphase, a tumour would develop.
Total = 15 15/4 = 3.75 Mark = 4
Technology and Society Score - 1
Scoring Guide
Bullet
Score
Rationale
1 &2
1
An explanation of genetic counselling is attempted. No
(total)
crosses are performed, and no method for decreasing the
incidence of the disease allele is given. The student states
that it is possible to figure out the risk of a couple having an
affected child but does not go beyond this statement.
Final Score 4(2) = 8/10 Science
1/5 Technology and Society
9/15 Final Score
25
Student Sample 4
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26
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Science Content Score - 3
Scoring Guide
Bullet Score Rationale
This student logically linked specific structures (retina,
optic nerve, fovea) to the tumour location, normal function,
and the disruption made by the tumour.
The student’s description of the pathway of conversion of
light into electrical impulses has gaps. Rods, cones, or
sensory receptors are not directly mentioned. (The fovea is
identified.) The occipital lobe is not identified. The link is
made that the optic nerve carries the affected images to the
cerebrum for interpretation.
The student attempts a diagram of the cell cycle. Interphase
is not shown. The student appears to equate “Cell Cycle”
with “mitosis of retinoblastoma cells” in the title above the
drawing.
The student states that the DNA of the retinoblastoma cells
would result in the production of abnormal proteins and that
cancer would result through accelerated cell division.
Total = 13 13/4 = 3.25 Mark = 3
27
Technology and Society Score - 3
Scoring Guide
Bullet Score Rationale
1 4 The student performs a cross involving a “normal”
individual and a heterozygous individual. The Punnett
square is correct; however, the interpretation of the results
is not quite correct. The student has indicated that there is a
50% chance of retinoblastoma occurring when, in fact, 50%
of the children will have the risk factor and be carriers of
the abnormal allele.
2 2 A method for decreasing the incidence of the disease is
suggested. The explanation “DNA reconstruction maybe
could be done in the Future” is not definitive enough to
merit a 3. (A method for decreasing the incidence of the
disease allele is identified.) Also, the student does not
explain how “monitoring individuals” so that the disease
can be “caught early” will eliminate the disease.
Total = 6 6/2 = 3.0 Mark = 3
Final Score 3(2) = 6/10 Science
3/5 Technology and Society
9/15 Final Score
An important point to note about the scoring guide is that a score of
1 is awarded if only one of the four bullets making up the Science
Scoring Guide for the question is answered. Even if the student
receives a very high score on the first bullet, he or she will receive a
score of 1 because he or she has not addressed the three other bullets
(3/4 of the question). For the Technology and Society Scoring
Guide, a score of 1 is given if only one of the two bullets is
addressed and it is scored as either 3 satisfactory or 2 limited. If
more than one bullet is addressed by the student, the student
automatically receives a score of 2 or higher for the answer.
General Comments About the New Open-Response Scoring Guide
The difference between an answer receiving a score of 2, 3, 4, or 5,
on either scale, depends on the amount of detail that is supplied in
the answer, the clarity of the communication, and whether the
student addresses all portions of the question. If the student is able
to support his or her answer through the use of diagrams, appropriate
vocabulary, and technologies, then a higher score is assigned.
28
Hardy-
NEW
Students can turn a poor answer into an excellent one by addressing
each aspect of the question specifically.
For example, one part of the retinoblastoma question required
students to “Provide the necessary details of the physiology of the
eye and brain.”
In student sample 3 (page 24), the student gave the following
response.
“Cones and rods are used to see color and shades of grey
respectively. The different images they receive are transmitted
to sensory nerves and then to the brain.”
An excellent response would be more detailed and specific, as in the
following example.
Light stimulates the cones (high-intensity light) and rods (low-
intensity light) thereby permitting colour vision and vision in
shades of black and grey, respectively. The rods and cones act
as sensory receptors. Once excited by light, they stimulate
impulses in the optic nerve. The optic nerve carries the impulses
to the occipital lobe of the cerebrum where they are interpreted.
Weinberg Calculations
The January 1999 written-response question 2 asked students to
calculate the frequency of a particular allele and the percentage of a
given population that are carriers. The question also required
students to show their work. Two examples of hypothetical
students’ responses are presented below. These show common
errors in communication and the mark, out of 5, that each student
would have received for their answers. The information given was
that 1/40 000 individuals in the population have the autosomal
recessive disorder.
Hypothetical response 1:
^ 40 000
0.000025
The frequency of the allele is 0.25%
p = 1-0.25
p = 0.75
2pq = 2(0.75)(0.25) = 0.375
The percentage of carriers in the population is 37.5%.
This student’s initial error is to confuse the frequency of the disorder
with the frequency of the recessive allele. It is a common error for
students to incorrectly use the allele frequency for the disorder
frequency and vice versa. Students should be comfortable doing
29
calculations using both types of starting data. Phenotypic evidence
can be used to determine the frequency of a disorder. Genetic
screening tests, if available, can be used to determine the frequency
of an allele.
Although this student’s first calculation is incorrect, the second
calculation, using the incorrect value for p is correct. Therefore, this
student would have received a 3/5 for the communication and
calculations.
Hypothetical response 2:
^ 40 000
q = 0.005
p = 1 - ^ = 0.75
/ = 0.99
2pq = 2(0.005X0.995) = 0.00995
Although this student’s mathematical communication is accurate, he
or she failed to state the answer to the second part of the question,
which required students to “calculate the percentage of the
population that are carriers.” (Answer: Approximately 1.0% of the
population are carriers). The marker is therefore unsure of whether
the student knows the meaning of the mathematical symbols he or
she is using. This student would have received a 4/5 for this portion
of the answer.
Implementation of the New Open-Response Scoring Guide
NEW The new scoring guide was implemented in the February marking
session of the January 1999 Diploma Examination. This marking
session provided positive evidence that the new scoring system is
fair to students, reliable, provides additional information for students
and educators, and effectively differentiates different levels of
student achievement.
The scoring system uses two scales, one for science and one for
technology and society. Jurisdiction and school reports provide
information on student performance for both scales. In conjunction with
the examination itself, these reports can be used to better interpret
specific areas of student strengths and weakness. Teachers surveyed
during the February marking session felt the new information available
with this scoring guide would be helpful in analyzing results. The
provincial results from the January 1999 Diploma Examination can be
used to illustrate this. The technology and society scale results for the
question revealed a higher proportion of no responses and zeros and a
lower average than the science scale results. Many students had
30
difficulty attempting Hardy-Weinberg calculations and were not able to
describe technologies or societal factors that might be reasonable
solutions to the problem stated. This is an area of the curriculum that
teachers in the province could target for improved learning strategies for
students. However, there was a higher proportion of students receiving
perfect scores on this scale than on the science scale. This result
suggests targeting these strategies to students at the acceptable standard
of achievement rather than students achieving at the standard of
excellence. Individual, school, and jurisdiction reports would enable
educators to determine if these were problem learning areas for their
group of students.
The division of the scoring criteria into two scales with five
divisions each provides more information to students and teachers
on how to achieve an acceptable or excellent standard of
achievement on this portion of the exam. The increased number of
divisions produces more identifiable steps for improvement. The
scoring guides for each examination are available on the Internet to
teachers and students and could be used to evaluate students’ ability
to answer this type of question and then illustrate what would be
required to improve their score. The greater number of divisions in
the scale should allow students to identify a reasonable improvement
goal.
Teachers surveyed during the February marking session felt that the
new scoring guide was fair to students. Many commented that the
scoring criteria described students’ achievement better than the one-
scale, four-point scoring system that was replaced. Students were
less likely to have responses that fell between the achievement levels
described. A very low third-read rate (less that 1%) in February
supports the teachers’ comments that student achievement was
assessed consistently and fairly using this scoring method.
Marks ranging from 0/15 to 15/15 were awarded using this scoring
method. The one-scale, four-point scoring system only allowed eight
different marks to be assigned to students based on the quality of
their responses. (The Examiners' Report for January 1999, available
to teachers on the extranet provides a graph of the distribution of
these marks on the January 1999 examination.) The new scoring
system was very effective in differentiating students’ levels of
achievement.
31
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