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January 1995 


Biology 30 

Grade 12 Diploma Examination 








^Iberia 

EDUCATION 


Copyright 1995, the Crown in Right of Alberta, as represented by the Minister of Education, Alberta 
Education, Student Evaluation Branch, 11160 Jasper Avenue, Edmonton, Alberta, T5K 0L2. All rights 
reserved. Additional copies may be purchased from the Learning Resources Distributing Centre. 

Special permission is granted to Alberta educators only to reproduce, for educational purposes and on a 
non-profit basis, parts of this examination that do not contain excerpted material only after the 
administration of this examination. 

Excerpted material in this examination shall not be reproduced without the written permission of the 
original publisher (see credits page, where applicable). 


UNIVERSITY LIBRARY 
UNIVERSITY OF ALBERTA 


January 1995 

Biology 30 

Grade 12 Diploma Examination 


Description 

Time: 2.5 h. You may take an 
additional 0.5 h to complete the 
examination. 

Total possible marks: 80 

This is a closed-book examination 
consisting of 

• 48 multiple-choice and 8 numerical - 
response questions each with a value 
of one mark 

• 2 written-response questions, each 
worth 12 marks 


This examination contains sets 
of related questions. 


A set of questions may contain 
multiple-choice and/or numerical - 
response and/or written-response 
questions. 

When required, a grey bar will be 
used to indicate the end of a set. 


Tear-out data pages are included at the 
back of this booklet. 

The perforated pages at the back of this 
booklet may be torn out and used for 
your rough work. No marks will be 
given for work done on the tear-out 
pages. 


Instructions 

• Fill in the information required on the 
answer sheet and the examination 
booklet as directed by the presiding 
examiner. 

• You are expected to provide your own 
scientific calculator. 

• Use only an HB pencil for the 
machine-scored answer sheet. 

• If you wish to change an answer, erase 
all traces of your first answer. 

• Consider all numbers used in the 
examination to be the result of a 
measurement or observation. 

• Do not fold the answer sheet. 

• The presiding examiner will collect 
your answer sheet and examination 
booklet and send them to Alberta 
Education. 

• Read each question carefully. 

• Now turn this page and read the 
detailed instructions for answering 
machine-scored and written-response 
questions. 



Multiple Choice 

• Decide which of the choices best 
completes the statement or answers 
the question. 

• Locate that question number on the 
separate answer sheet provided and 
fill in the circle that corresponds to 
your choice. 

Example 

This examination is for the 
subject of 

A. biology 

B. physics 

C. chemistry 

D. science 

Answer Sheet 

• (D © ® 


Numerical Response 

• Record your answer on the answer 
sheet provided by writing it in the 
boxes and then filling in the 
corresponding circles. 

• If an answer is a value between 0 and 1 
(e.g., 0.25), then be sure to record the 0 
before the decimal place. 

• Enter the first digit of your answer 
in the left-hand box and leave any 
unused boxes blank. 


Examples 

Calculation Question and Solution 

The average of the values 21.0, 25.5, and 
24.5 is . 

(Record your answer to three significant 
digits in the numerical-response section of 
the answer sheet.) 


Average = (21 .0 + 25.5 + 24.5)/3 
= 23.666 

= 23.7 (rounded to three digits) 


Record 23.7 on the 
answer sheet 


2 

3 

. 

7 


© 

• 


® 

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11 



Written Response 


Correct-order Question and Solution 

When the following subjects are arranged in 

alphabetical order, the order is . 

(Record your four-digit answer on the numerical- 
response section of the answer sheet.) 

1 physics 

2 chemistry 

3 biology 

4 science 

Answer 3214 


• Write your answers in the examination 
booklet as neatly as possible. 

• For full marks, your answers must be 
well organized and address all the main 
points of the question. 

• Relevant scientific, technological, and/or 
societal concepts and examples must be 
identified and explicit. 


Record 3214 on the 
answer sheet 


3 

2 

/ 

4 


0 

© 


© 

© 

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© 

© 

• 

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• Descriptions and/or explanations of 
concepts must be correct and reflect 
pertinent ideas, calculations, and 
formulas. 

• Your answers should be presented in a 
well-organized manner using complete 
sentences, correct units, and significant 
digits where appropriate. 


Selection Question and Solution 

The birds in the following list are numbered 

(Record your answer in ascending numerical order 
in the numerical-response section of the answer 
sheet.) 

1 dog 

2 sparrow 

3 cat 

4 robin 

5 chicken 

Answer 245 


Record 245 on the 
answer sheet 


2 

4 

5 



© 

0 


© 

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ill 


Do not turn the page to start the 
examination until told to do so by the 
presiding examiner. 


Digitized by the Internet Archive 
in 2016 


https://archive.org/details/gf^de12diplomae995albe_11 


Scientists study disorders of the nervous and endocrine system to find treatments for 
the disorders and to extend their knowledge of these systems. 


Use the following information to answer the next two questions . 


Alzheimer’s disease is a degenerative, incurable, and often fatal brain disorder. It is 
characterized by progressive memory loss and the inability to think, speak, or perform basic 
tasks. 

Autopsy studies of the brain tissue of Alzheimer’s patients usually show abnormalities such as: 

• tangled and twisted protein filaments within neuron cell bodies 

• clusters of degenerated axon terminals 

• death of certain neurons that are responsible for the production of a common 
neurotransmitter 

• growth within neurons of patches composed of a protein called beta-amyloid 


1. Within a neuron, the production of beta-amyloid patches is primarily controlled by 
substances in the 


A. myelin sheath 

B. cell body 

C. dendrite 

D. axon 


2. Which secretion is most likely lacking in the brain of an Alzheimer’s patient? 


A. ATP 

B. Acetylcholine 

C. Transfer RNA 

D. Cholinesterase 


1 


Use the following information to answer the next two questions. 


Huntington Disease 

Many genetic disorders in humans result in some behavioural abnormality. One example is 
Huntington disease (HD), which is controlled by the presence of a dominant gene. This disease 
affects all parts of the nervous system, including the brain. Symptoms of HD usually appear 
after age 40 and include a gradual loss of motor function and coordination. Degeneration of the 
nervous system is progressive and produces personality changes. Affected individuals become 
unable to care for themselves. These symptoms indicate that the disease affects some parts of 
the brain more than others. 


3. Which row identifies the degree to which certain parts of the brain are most likely 
affected by HD? 


Row 

Relative Effect of HD on Parts of the Brain 

Cerebrum 

Cerebellum 

Pituitary 

Hypothalamus 

A 

slight 

slight 

significant 

significant 

B 

significant 

slight 

significant 

slight 

C 

slight 

significant 

slight 

significant 

D 

significant 

significant 

slight 

slight 


Use this additional information to answer the next question. 


A person with HD has elevated levels of quinolinic acid. Quinolinic acid is an amino acid that 
excites neurons but also acts as a neurotoxin (poison). It is produced when tryptophan is 
metabolized by the body. 


4. This additional information supports the hypothesis that the gene that causes HD is 

A. a structural gene that contains information used to produce an enzyme that 
metabolizes tryptophan 

B. a mutant gene that promotes the action of enzymes that metabolize 
quinolinic acid 

C. a regulatory gene that produces an enzyme that metabolizes quinolinic acid 

D. an oncogene that activates enzymes that metabolize tryptophan 


2 


Use the following list to answer the next question. 


Some Events that Occur in the Nervous System 

1 A motor neuron stimulates the effector. 

2 Nerve tracts in the medulla oblongata are activated. 

3 The brain interprets the sensation of pain. 

4 A sensory neuron is depolarized. 

5 A receptor is stimulated. 

6 The motor cortex initiates movement. 

7 An impulse is initiated in an intemeuron. 


Numerical Response 


ill When a person’s hand touches a very hot object, a reflex arc is activated, which 
causes the person to quickly withdraw the hand. Provide the correct sequence of 
events that occurs in this reflex arc by selecting four events from the list and 
arranging them in the proper order. 

Answer: 

First event Second event Third event Fourth event 

(Record your four-digit answer in the numerical-response section of the answer sheet.) 


5. Many blind people have damaged 
sensory receptors in the eyes but 
undamaged optic nerves. To assist 
these people, an artificial eye would 
have to replace the function of which 
structure shown in the diagram at 
the right? 

A. 1 

B. 2 

C. 3 

D. 4 



3 



6. An optometrist who wants to dilate the pupil to study the interior of the eye would 
likely administer a drug to stimulate the 

A. central nervous system 

B . somatic nervous system 

C. sympathetic nervous system 

D. parasympathetic nervous system 


Use the following information to answer the next two questions. 


Damage to hair cells in the inner ear was thought to permanently impair the sense of balance. 
Recent research indicates that humans and guinea pigs have the ability to form new hair cells in 
the utricle. In experiments, these hair cells were chemically destroyed. After some time, new 
hair cells formed. These new cells eventually connected with neurons. Researchers have yet to 
discover the internal body stimuli that trigger the formation of the new cells. 


7. In the experiments, newly formed hair cells connected with neurons. What type of 
neurons would these be? 

A. Motor neurons 

B . Sensory neurons 

C. Somatic neurons 

D. Association neurons 


8. In order to develop a procedure that would restore hearing in individuals with 
hearing loss caused by damage to hair cells, similar research must be done on the 
hair cells found in the 

A. saccule 

B . cochlea 

C. auditory canal 

D. semicircular canals 


9. Both giantism and dwarfism are disorders caused by a malfunction of 
which gland or glands? 


A. 

Gonads 

B. 

Thyroid 

C. 

Pituitary 

D. 

Adrenals 


4 


Use the following information to answer the next question. 


Possible Symptoms of Diabetes Mellitus 

1 

Increased insulin production 

2 

Decreased insulin production 

3 

Increased blood glucose level 

4 

Decreased blood glucose level 

5 

Increased cellular absorption of glucose 

6 

Decreased cellular absorption of glucose 

7 

Increased urine production 

8 

Decreased urine production 


Numerical Response 


|3 Pat, a 14 year-old student, has diabetes mellitus. Which four of these symptoms 
would Pat likely show, if untreated? 

Answer: 

(Record your four-digit answer in ascending numerical order in the numerical-response section of 
the answer sheet.) 


10 . Which hormone acts antagonistically (oppositely) to insulin? 

A. Somatotropin 

B . Epinephrine 

C. Thyroxine 

D. Glucagon 


5 



Use the following information to answer the next three questions. 


Amino Acid Sequence in Insulin 

Dr. Frederick Sanger and his colleagues in England worked out the exact sequence of 5 1 amino 
acids in the insulin molecule. One part of that sequence of amino acids is: 

— alanine — lysine — proline — threonine — 


11. Which sequence of nitrogen bases in DNA encodes information to make this part of 
the insulin molecule? 

A. — CG A — TTT — GGT — TGA — 

B. — CGT — AAA — GGT — ACT — 

C. — GCU — AAA — CCA — ACU 

I). — GCG — AAG — CCA — ACG — 


12. Which change in the structure of mRNA would not cause the amino acid threonine 
to be replaced with another amino acid? 

A. ACG -> UCG 

B. ACA -> AUC 

C. ACC -> UGG 

D. ACU -> ACC 


13. Although all normal human insulin molecules contain a specific sequence of amino 
acids, the nucleotide sequence in the insulin gene may vary slightly from person to 
person. This variation can occur because 

A. the type of amino acids in insulin does not affect its function 

B. a specific amino acid can be represented by more than one codon 

C. the sequence of amino acids in insulin does not affect its function 

D . a specific codon can be represented by more than one polypeptide 


6 


Use the following information to answer the next question. 


Scientists from the All India Institute of Medical Sciences in New Delhi recently 
conducted research on the reproductive endocrine functions of men with 
hypothyroidism. Their objective was to study the relationship between thyroid 
hormones (triiodothyronine and thyroxine)* and hormones related to reproduction. 
Eight men with symptoms of hypothyroidism were chosen for the study. Blood 
samples from these men were analyzed before treatment for hypothyroidism began. 
Some of the data are presented in table 1 . 

Table 1: 

Data Obtained from Eight Patients with Hypothyroidism and 
Normal Ranges of Some Hormone Concentrations in Blood 

Patient 

Age 

(years) 

TSH 

(units) 

Triiodothyronine 

(units) 

Thyroxine 

(units) 

1 

43 

>100 

36.0 

2.2 

2 

26 

>100 

32.0 

0.0 

3 

45 

>100 

26.0 

1.0 

4 

26 

>100 

28.0 

0.5 

5 

55 

>100 

40.0 

0.5 

6 

62 

>100 

50.0 

3.0 

7 

37 

>100 

46.0 

2.0 

8 

41 

>100 

0.7 

0.7 

Normal 

range 

— 

0-8 

80-160 

5-11 

* Two thyroid hormones with similar functions 


Written Response - 12 marks 


1 1, | a. Based on the data in table 1, define hypothyroidism in terms of the 
function of the thyroid gland. 


b. Explain why TSH concentrations in the eight patients differed from the 
normal range? 


Continued 


For 

Department 
Use Only 


(1 mark) 


(1 mark) 


7 


For 

Department 
Use Only 

(1 mark) 


c. Describe one possible treatment for hypothyroidism suggested by the 
data in table 1. 


(3 marks) 


d. Identify three symptoms of hypothyroidism, other than hormone 

concentrations in the blood or effects on reproduction, likely shown by 
the patients. 


Before treatment for hypothyroidism began, blood samples from the eight patients 
were tested for the presence of some hormones related to reproduction. Similar 
tests were performed after treatment for hypothyroidism was complete. A control 
group was tested in a similar manner. The average blood concentrations of these 
hormones related to reproduction are shown in table 2. 

Table 2: Average Blood Concentrations of Some Hormones Related to 

Reproduction in Eight Patients Before and After Treatment for 
Hypothyroidism and in a Control Group 

Group 

Hormone Concentration 
(units/L of blood) 

LH 

FSH 

Testosterone 

Patients before treatment 

19.0 

6.0 

5.5 

Patients after treatment 

7.0 

3.0 

13.0 

Control 

6.0 

3.5 

23.5 


Continued 


8 


e. Draw a bar graph to illustrate the data in table 2. 



f. Why would a man with hypothyroidism produce fewer sperm than a 
man with a normally functioning thyroid? 


For 

Department 
Use Only 

(3 marks) 


(1 mark) 


g. Explain the differences in the production of FSH and testosterone by 
the group of eight patients before treatment and by the control group. 


(2 marks) 



9 


Reproductive processes may be affected by disease, the environment, or the use of 
technology. 



14 . The sample of tissue used to make this cross section would be obtained from the 

A. testis 

B. epididymis 

C. vas deferens and urethra 

D. seminal vesicle and prostate 


15 . The cell that contains a single X or Y chromosome is labelled 

A. 1 

B. 2 

C. 3 

D. 4 


10 


Use the following information to answer the next three questions. 



A. fertilization of eggs 

B . development of follicles 

C. movement of sperm into the uterus 

D. secretion of estrogen and progesterone 


17. Gonorrhea, a sexually transmitted disease, may cause an infection in the structure 
labelled 4. This condition could result in sterility because 

A. ovulation would be disrupted 

B . menstruation would not occur 

C. implantation would be prevented 

D. fertilization would not be possible 


18. Which structure produces a hormone that prevents uterine contraction during the 
first weeks of pregnancy? 

A. 2 

B. 3 

C. 4 

D. 5 


11 


Use the following information to answer the next question. 


A Reproductive Technology 

Reproductive technology may be used when people have difficulty conceiving children. 

In vitro fertilization (IVF) is a procedure in which eggs are removed from a woman’s ovary and 
placed in a culture dish containing sperm from a male donor. After fertilization occurs, an 
embryo is inserted into the uterus through the vagina. 


19. The female menstrual cycle has several phases. Implantation of the fertilized egg 
in the IVF procedure would have the greatest chance of success if it were done 
during the 

A. corpus luteal phase when progesterone levels are high 

B. corpus luteal phase when FSH levels are high 

C. follicular phase when estrogen levels are high 

D. follicular phase when LH levels are high 


20. Researchers have discovered that exposure to an electric field causes the caps 
(acrosomes) of sperm to burst before contact with ova. How might exposure of 
sperm to an electric field affect the success rate of in vitro fertilization? 

A. The success rate would improve because sperm would be more motile. 

B . The success rate would decline because the nuclei of sperm would be altered. 

C. The success rate would decline because sperm would not be able to 
penetrate ova. 

D. The success rate would improve because more nutrients would be available to 
ensure survival of sperm. 


21. In humans, a sperm and an egg are similar in that both 

A. require normal body temperature for maturation and development 

B. contribute equally to the cytoplasm of the zygote 

C. are inactivated by a solution with a pH of 7 to 9 

D. contain the same number of chromosomes 


12 


22. Which statement about the events that occur during childbirth is correct? 

A. An increase in prolactin causes relaxation of pelvic ligaments. 

B. An increase in oxytocin causes contraction of uterine muscles. 

C. A decrease in estrogen causes contraction of abdominal muscles. 

D. A decrease in progesterone causes relaxation of placental membranes. 


Use the following information to answer the next three questions. 


Fetal Alcohol Syndrome 

Fetal Alcohol Syndrome (FAS) is a condition that develops in a fetus as a result of the 
ingestion of alcohol (ethanol) by a pregnant woman. The effects on the fetus include mental 
retardation, slow growth, and the development of a small head, narrow eye slits, and a 
defective heart. These changes are not reversible. Pregnant women who consume 25 mL of 
pure alcohol daily (equivalent to two or three bottles of beer) have a 2% chance of giving birth 
to a child with FAS. 

Most doctors urge pregnant patients to avoid the use of drugs of all kinds. The use of drugs 
such as alcohol, heroin, cocaine, and morphine may cause a child to be bom addicted. 


23. Some women who consume 25 mL of absolute alcohol daily may have a 

significantly higher than 2% risk of having a child with FAS. The additional factor 
that likely contributes most to this increased risk is a woman’s 

A. body mass 

B . emotional state 

C. exercise routine 

D. choice of brand of alcoholic beverage 


24. An infant can be bom with a dmg addiction because 

A. a child can acquire all of its mother’s habits 

B . a child can inherit some of its mother’ s addictions 

C. placental membranes promote the mixing of maternal blood with fetal blood 

D. placental membranes are permeable to substances other than nutrients and wastes 

Continued 


13 


Use this additional information to answer the next question. 


Alcohol is normally metabolized as follows: 


Alcohol 


Alcohol ; 
dehydrogenase 


Acetaldehyde 


Aldehyde 


dehydrogenase 


Acetic acid 


Acetaldehyde is a product of alcohol metabolism that contributes to fetal damage. Acetic acid 
may be used for energy production or fat synthesis. 


25. Which row indicates the rate of action of two enzymes in a pregnant woman’s body 
that would put a fetus at the greatest risk of developing FAS? 


Row 

Relative Rate of Action of Enzymes in a Pregnant Woman’s Body 

Alcohol dehydrogenase 

Aldehyde dehydrogenase 

A 

fast 

fast 

B 

fast 

slow 

C 

slow 

fast 

D 

slow 

slow 


14 


Data collected by scientists reveal interactions among organisms and populations. 


Use the following graph to answer the next two questions. 


Population of Mice in a Farmer’s Field (1979-1992) 
I II III 



26. On the graph, sections I, II, and III respectively show the 

A. stationary phase, growth phase, and lag phase of a closed population 

B . lag phase, growth phase, and stationary phase of a closed population 

C. stationary phase, growth phase, and lag phase of an open population 

D. lag phase, growth phase, and stationary phase of an open population 


27. The trend shown in section II of the graph might have continued for an extra year if 

A. predators had been allowed to roam freely 

B. irrigation had increased the growth of vegetation 

C. more consumers had been added to the environment of the mice 

D. traps had been set to prevent emigration and immigration of mice 


15 


Use the following information to answer the next three questions. 


Historical plant populations can be 
examined by removing core samples of 
earth and microscopically examining 
them for the types of pollen present. 
The graph shows an analysis of pollen 
collected at various depths from a 
grassland site in southern Alberta. The 
samples were obtained by drilling into 
the earth and then removing the entire 
core sample intact. The total depth 
sampled has accumulated since the end 
of the last glacial period, approximately 
13 000 years ago. Each 0.3 m of depth 
represents about 1 000 years. 



Grasses 

Spruce 

Fir 

Pine 

Mixed deciduous 


Pollen Core Samples Taken from a 
Grassland Area in Southern Alberta 



Percent of sample 


28. The change in the vegetation over the last 13 000 years is called 

A. succession 

B. colonization 

C. serai staging 

D. a climax community 


Continued 


16 





29. Select the row that correctly identifies the sequence of communities this site has 
supported from 13 000 years ago up to and including the present. 


Row 

Sequence of Communities 

A 

Grass-deciduous — > pine-spruce — > pine — > fir-spruce 

B 

Fir-spruce — > pine-deciduous — > pine — » grass-deciduous 

C 

Pine-grass — » pine-fir— > pine- spruce —> spruce-deciduous 

D 

Grass-deciduous — » pine — » fir-spruce — > spruce-pine 


30. According to the data, in what way and when did the climate dramatically change in 
southern Alberta? 

A. The climate became warm and dry 12 000 to 13 000 years ago. 

B. The climate became cool and moist 7 000 to 8 000 years ago. 

C. The climate became cool and moist 3 000 to 4 000 years ago. 

D. The climate became warm and dry 1 000 to 2 000 years ago. 


17 


Use the following information to answer the next two questions. 


In the Antarctic, James McClintock 
noticed that small amphipods 
(crustaceans) captured small free- 
floating snails. The snails were 
bright orange in colour and half the 
size of the amphipods. An 
amphipod held a snail on its back 
with 4 of its 14 legs. The snails 
were released unharmed when it got 
dark. 

In a laboratory, McClintock 
separated populations of snails from 
populations of amphipods and 
placed some small fish with each 
group. The fish ate the amphipods 
but ate only a few of the snails and 
immediately spit them out. 

When amphipods with snails on 
their backs were placed in the tank 
that originally contained snails, the 
fish did not eat the amphipods and 
actually avoided them. McClintock 
ground up some snails and formed 
them into pellets to feed the fish. 
When these pellets were fed to the 
fish, they immediately spit them out. 


An Amphipod with a 
“Piggy-Backing” Snail 


Amphipod 



31. The term that best describes the relationship between the amphipod and the snail is 


A. commensalism 

B. mutualism 

C. parasitism 

D. predation 


32. Why did the fish not eat the amphipods with snails on their backs? 

A. The snails provided camouflage for the amphipods. 

B. The fish learned to avoid the amphipods because the amphipods mimicked 
the snails. 

C. The foul taste of the snails was absorbed by the amphipods and the fish 
learned to avoid them. 

D. The fish avoided eating amphipods carrying snails because they recognized 
the warning coloration. 


18 


Use the following information to answer the next four questions. 


A Zebra Mussel Takeover 

The European zebra mussel, a small bivalve mollusk, was first discovered in North America in 
1988. It was found in Lake St. Clair, which connects Lake Huron to Lake Erie. By 1991, the 
mussel had spread to all the Great Lakes as well as the Illinois River. Scientists think the 
mussels were carried into the Great Lakes in the ballast water of freighters. During the 
summer of 1993, the Mississippi River flooded its banks and picked up zebra mussels from 
the Illinois River. The flood waters carried the mussels into creeks, lakes, and ponds along its 
southerly route. 

Zebra mussels spawn up to five times a year and release about a million eggs per spawning. 
The larvae travel in water for five to 30 days before they settle onto something stationary. The 
mussels secrete strong threads that tether them to submerged rocks, docks, hulls of boats, and 
sewage and water treatment intake-pipes. As many as 94 000 zebra mussels can occupy a 
surface area of 1 m 2 . 

Zebra mussels feed by drawing water over their gills with siphons. They compete with native 
mussels and fish for suspended food such as algae. Natural predators, such as ducks and 
crayfish, have not been able to keep them under control. The use of chemical pesticides, such 
as chlorine, is costly and can lead to the formation of cancer-causing agents in water systems. 



33. The abiotic factor that caused the zebra mussel to spread from the Great Lakes 

south into the United States rather than north into Canada was the difference in the 

A. diversity of predators in Canada and the United States 

B. food supply in the waterways of the United States and Canada 

C. level of industrial development of the United States and Canada 

D. natural water drainage patterns of Canada and of the United States 

Continued 


19 


34. The spread of the European zebra mussel in North America from 1988 through 
1993 is an example of a species with populations that are distributed 


A. in clumps and K-selected 

B. randomly and K-selected 

C. in clumps and r-selected 

D. randomly and r-selected 


Numerical Response 


Q Suppose that a population of 3 500 mussels occupied a rectangular territory 2.00 m 
by 2.00 m. Calculate the average density of this mussel population. 

Answer: /m 2 

(Record your answer to three significant digits in the numerical-response section of the 
answer sheet.) 


Numerical Response 


gH Given that one mussel releases one million eggs per spawning and assuming that 

the survival rate is 0.020%, calculate the maximum number of surviving individuals 
produced in two generations originating with one mussel. Express your answer in 
scientific notation in the form w x 10^ mussels. What is the value of w when the 
answer is expressed in scientific notation? 

Answer: 

(Record your answer to two significant digits in the numerical-response section of the answer sheet.) 


20 




An understanding of the principles of cell division and genetics is required to make 
appropriate choices about the use of biotechnology. 


Use the following information to answer the next two questions. 


Life Cycle of Sea Lettuce (Green Alga) 



35. Which conclusion about the life cycle of sea lettuce is supported by the diagram? 

A. The spore is diploid. 

B . The zygote is haploid. 

C. The sporophyte is diploid. 

D. The gametophyte is diploid. 


36. Assuming that the diploid chromosome number for this species is 12, what is the 
chromosome number at stages labelled W, X, and Y respectively? 


A. 6, 6, and 12 

B. 6, 12, and 12 

C. 6, 12, and 24 

D. 12, 12, and 24 


21 





37. Compared to asexual reproduction, one advantage of sexual reproduction is the 

A. development of haploid individuals 

B . development of genetically identical individuals 

C. increased production of offspring in one life cycle 

D. increased chance of producing offspring adaptable to environmental change 


Use the following information to answer the next question. 


Events That Occur During DNA Replication 
(Arranged in Random Order) 

1 Hydrogen bonds form between nucleotide bases. 

2 An enzyme acts like a pair of scissors to break the weak hydrogen bonds between the 
nitrogen bases. 

3 At the replication fork, the DNA template strands determine the sequence of the 
nucleotides that are being replaced. 

4 A purine or pyrimidine is inserted on a matching nucleotide of the polynucleotide strand. 

5 Nitrogen bases of the polynucleotide strand separate. 


38. The correct sequence of events that occurs during DNA replication is 

A. 2, 3, 5, 1, and 4 

B. 2, 5, 3, 4, and 1 

C. 3, 2, 5, 4, and 1 

D. 3, 5, 2, 1, and 4 


22 


Use the following diagram to answer the next two questions. 



39. What is a likely cause of the abnormality shown in this karyotype? 

A. Crossing over of autosomes 

B. Nondisjunction of autosomes 

C. Crossing over of sex chromosomes 

D. Nondisjunction of sex chromosomes 


40. Which technology would be best suited to identify a fetus with this disorder? 

A. Ultrasound 

B. X-ray imaging 

C. Amniocentesis 

D. DNA fingerprinting 


23 


Use the following information to answer the next question. 


Some Characteristics of Cell Division 

1 DNA is replicated just before cell division begins. 

2 Duplicated chromosomes pair with their homologues. 

3 Diploid cells are ultimately produced. 


41. Which row correctly identifies the type of cell division described by each 
numbered statement? 


Row 

Statement 1 

Statement 2 

Statement 3 

A 

both mitosis and 
meiosis 

meiosis only 

mitosis only 

B 

both mitosis and 
meiosis 

both mitosis and 
meiosis 

mitosis only 

C 

mitosis only 

meiosis only 

both mitosis and 
meiosis 

D 

mitosis only 

both mitosis and 
meiosis 

meiosis only 


Use the following information to answer the next two questions. 


In shorthorn cattle, coat colour may be red, white, or roan. Crosses between a red bull and a 
white cow produce only roan offspring. 


42. The alleles for coat colour in shorthorn cattle demonstrate 

A. sex-linkage 

B . crossing over 

C. codominance 

D. nondisjunction 



El If a roan shorthorn is crossed with a white-coated shorthorn, what is the 
probability that the offspring will be a roan shorthorn? 

Answer: 

(Record a value from 0 to 1 rounded to two significant digits in the numerical-response section of the 
answer sheet.) 


24 


Use the following information to answer the next three questions. 


In guinea pigs, black coat (B) is dominant over white coat (b), and straight hair (S) is dominant 
over curly hair (s). Each pair of alleles assorts independently. 

Two guinea pigs mated. The types of gametes produced by the parents are shown in the 
Punnett square. Possible genotypes of offspring resulting from the mating are indicated in the 
centre of the Punnett square as genotype 1 to genotype 8. 


X 

BS 

Bs 

bS 

bs 

Bs 

genotype 1 

genotype 2 

genotype 3 

genotype 4 

bs 

genotype 5 

genotype 6 

genotype 7 

genotype 8 


43. Which row correctly identifies the phenotypes of both parents? 


Row 

a 

9 

A 

black-straight 

black-curly 

B 

black-straight 

black-straight 

C 

black-curly 

white-straight 

D 

white-curly 

black-straight 


44. The Punnett square indicates that the parent guinea pigs 

A. produced eight offspring, all with different genotypes 

B. produced eight offspring, half of which have at least one of the dominant traits 

C. are likely to produce a higher proportion of offspring with black coats than 
offspring with curly hair 

D. are likely to produce a higher proportion of offspring with white coats than 
offspring with straight hair 


Numerical Response 


ES Choose the correct genotype number for each description of guinea pig offspring. 


Genotype number: 

Description of offspring: Homozygous Have the same White coat colour 

recessive for genotype as and heterozygous 

both traits genotype 3 for hair type 

(Record your three-digit answer in the numerical-response section of the answer sheet.) 


25 



45. A new insecticide functions as a mutagen. It seems to have little effect when 

applied to an adult insect population. However, the insect’s offspring have a variety 
of lethal defects. This new insecticide likely affects the process of 

A. mitosis in gonads 

B. meiosis in gonads 

C. mitosis in somatic cells 

D. meiosis in somatic cells 


Use the following information to answer the next three questions. 


Phenylketonuria 

Phenylketonuria (PKU) is a genetic disorder, the symptoms of which result from the inability of 
a person to produce the enzyme necessary to metabolize the amino acid phenylalanine. 
Production of the normal enzyme is controlled by a dominant allele. Without this enzyme, 
phenylalanine accumulates in a person’s body and causes mental retardation by inhibiting the 
normal development of the nervous system. 

The symptoms of PKU are not usually evident immediately at birth, but develop rapidly after 
birth if an affected child is not put on a special diet. After ten years of age, the nervous system 
is fully developed and the child’s diet need no longer be strictly controlled. 


46. The initial cause of PKU in an affected child likely results from the presence 
of abnormal 

A. ribosomal RNA 

B. messenger RNA 

C. DNA in cell nuclei 

D. DNA in cell mitochondria 


Continued 


26 


Use this additional information to answer the next two questions. 



47. Which is a valid conclusion about the genotypes for the alleles for PKU of 

individuals II, 2 and II, 3? 

A. They are both heterozygous because their sister has PKU. 

B. They are both homozygous-dominant because their parents have 
normal phenotypes. 

C. Without further evidence, it cannot be determined if both are 
homozygous-dominant or heterozygous. 

D. Without further evidence, it cannot be determined if both are 
homozygous-recessive or heterozygous. 


Numerical Response 


ftfl If the individuals in this pedigree represented a distinct population, how many of 
the 21 people could be expected to be heterozygous for PKU? 

Answer: people 

(Record your answer in the numerical-response section of the answer sheet.) 


27 



Use the following information to answer the next two questions. 


Hemophilia is a disorder characterized by abnormal blood clotting. This disorder is an 
X-linked recessive trait. 


48. A man who does not have hemophilia, but whose father did, is married to a woman 
who has no history of hemophilia in her family. Would genetic screening be 
necessary if this woman gets pregnant? 

A. No, because there is little probability that the disorder would occur regardless 
of the sex of the offspring. 

B. Yes, because the man’s father had hemophilia and it may skip a generation. 

C. No, because there is only a 25% chance that a male child would get the 
disorder. 

D. Yes, because there is a high probability of mutation for X-linked genes. 


Numerical Response 


KJ A normal woman whose father had hemophilia is married to a man who has 
hemophilia. If they have a child, what is the probability that the child would 
have hemophilia? 

Answer: 

(Record a value from 0 to 1 rounded to two significant digits in the numerical-response section of the 
answer sheet.) 


28 



Use the following information to answer the next question. 


In the 19th century, individuals who were not among the “normal” population were often thought 
to be failures or defectives. Early in the 20th century, the interaction of genetics, law, and society 
resulted in policies of enforced sterilization, restrictive immigration, and institutionalization of 
those thought to be genetic defectives. As this century closes, society will have difficult choices to 
make about the legality, morality, and economics of applying genetic knowledge and technology. 
The difficulty of this situation is summarized in the words of a famous geneticist, Theodosius 
Dobzhansky (b.1900 - d.1975): 

“If we enable the weak and the deformed to live and produce more of their kind, we face the 
prospect of a genetic twilight (decline). But if we let them die or suffer when we can help 
them, we face the certainty of a moral twilight.” 


Written Response - 12 marks 


1 2. | Consider the following proposal: 

People with genetic abnormalities should not be discouraged from having families. 
Doctors should attempt to treat every genetically related health problem and to keep 
people alive at all cost. 

If this proposal were initiated, there would be many effects on our society. Describe 
three ethical medical technologies that would reduce the financial costs created by 
initiating this proposal. Evaluate the proposal from both a genetic and a moral point 
of view. 

Your response should include the following information: 

• A description of three medical technologies that are ethical and that would likely 
reduce some of the financial costs created by initiating the proposal 

• A balanced argument for and against the proposal from the scientific perspective 
of a geneticist 

• A balanced argument for and against the proposal from the perspective of a policy 
maker (e.g., a politician or a religious leader) 


29 


Continued 


Continued 


30 


You have now completed the examination. If you have time , 
you may wish to check your answers. 


31 



BIOLOGY DATA 





Symbol 

Description 

A 

area 

B 

births during time interval 

b 

per capita births ( 

D 

deaths during time interval 

d 

per capita deaths (^yy) 

D P 

population density 

K 

carrying capacity 

N 

population size 

AN 

change in population size 

PG% 

population growth (percent) 

r 

per capita population growth rate 
(b-d) 

V 

volume 


Equations 


Subject 


Equation 

Hardy- Weinberg principle 

p 1 +2pq + q i =\ 



n N 

N 

Population density 

Dp — or Dp — 

A 

Change in population size 

AN = (factors that increase pop.) — (factors that decrease pop.) 

AN x 100% 

Population growth (%) 

= 

N 





BIOLOGY DATA 


Abbreviations for Some Hormones 


Hormone 

Abbreviation 

Adrenocorticotropin hormone 

ACTH 

Antidiuretic hormone 

ADH 

Follicle stimulating hormone 

FSH 

Human chorionic gonadotropin 

HCG 

Luteinizing hormone 

LH (formerly ICSH in males) 

Parathyroid hormone 

PTH 

Prolactin 

PRL 

Somatotropin (human growth hormone or growth hormone) 

STH (HGH or GH) 

Thyroid stimulating hormone 

TSH 


Pedigree Symbols 


□ 

o 

O-n 

o-n 

■ OtO 

■ [W 


Male 

Female 


Mating 


Mating between 
close relatives 

Offspring listed in 
birth order. Roman 
numerals symbolize 
generations. Arabic 
numbers symbolize 
birth order within 
generation. 



Identical 

twins 


Non-identical 

twins 




Affected 

individuals 



Deceased 

offspring 


Offspring of 
unknown sex 



BIOLOGY DATA 


Messenger RNA Codons and Their Corresponding Amino Acids 



S 

E C 

O 

N D 


B 

A 

S E 




u 

c 

A 

G 



F 


uuu 

Phe 

ucu 

Ser 

UAU 

Tyr 

UGU 

Cys 

U 

T 


U 

uuc 

Phe 

ucc 

Ser 

UAC 

Tyr 

UGC 

Cys 

c 


I 


UUA 

Leu 

UCA 

Ser 

UAA 

STOP** 

UGA 

STOP** 

A 

H 



UUG 

Leu 

UCG 

Ser 

UAG 

STOP** 

UGG 

Trp 

G 


R 







I 



CUU 

Leu 

ecu 

Pro 

CAU 

His 

CGU 

Arg 

U 


S 

C 

cue 

Leu 

ccc 

Pro 

CAC 

His 

CGC 

Arg 

C 

R 



CUA 

Leu 

CCA 

Pro 

CAA 

Gin 

CGA 

Arg 

A 


T 


CUG 

Leu 

CCG 

Pro 

CAG 

Gin 

CGG 

Arg 

G 

D 











AUU 

lie 

ACU 

Thr 

AAU 

Asn 

AGU 

Ser 

U 



A 

AUC 

lie 

ACC 

Thr 

AAC 

Asn 

AGC 

Ser 

C 


B 


AUA 

lie 

ACA 

Thr 

AAA 

Lys 

AGA 

Arg 

A 

B 



AUG 

Met or START* 

ACG 

Thr 

AAG 

Lys 

AGG 

Arg 

G 


A 







A 



GUU 

Val 

GCU 

Ala 

GAU 

Asp 

GGU 

Gly 

U 


S 

G 

GUC 

Val 

GCC 

Ala 

GAC 

Asp 

GGC 

Gly 

C 

S 



GUA 

Val 

GCA 

Ala 

GAA 

Glu 

GGA 

Gly 

A 


E 


GUG 

Val 

GCG 

Ala 

GAG 

Glu 

GGG 

Gly 

G 

E 


* Note: AUG is an initiator codon but also codes for the amino acid methionine. 
** Note: UAA, UAG, and UGA are terminator codons. 


Abbreviations for Amino Acids Information About Nitrogen Bases 


Amino Acid 

Abbreviation 

Alanine 

Ala 

Arginine 

Arg 

Asparagine 

Asn 

Aspartate 

Asp 

Cysteine 

Cys 

Glutamate 

Glu 

Glutamine 

Gin 

Glycine 

Gly 

Histidine 

His 

Isoleucine 

He 

Leucine 

Leu 

Lysine 

Lys 

Methionine 

Met 

Phenylalanine 

Phe 

Proline 

Pro 

Serine 

Ser 

Threonine 

Thr 

Tryptophan 

Trp 

Tyrosine 

Tyr 

Valine 

Val 


Nitrogen Base 

Classification 

Abbreviation 

Adenine 

Purine 

A 

Guanine 

Purine 

G 

Cytosine 

Pyrimidine 

C 

Thymine 

Pyrimidine 

T 

Uracil 

Pyrimidine 

U 












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