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I N S E R T S T U D E N T I . D . N U M B E R ( P E N )

S T I C K E R I N T H I S S P A C E

AUGUST 1999

PROVINCIAL EXAMINATION

MINISTRY OF EDUCATION

BIOLOGY 12

GENERAL INSTRUCTIONS

1. Insert the stickers with your Student I.D. Number (PEN) in the allottedspaces above and on the back cover of this booklet. Under nocircumstance is your name or identification, other than your StudentI.D. Number, to appear on this booklet.

2. Ensure that in addition to this examination booklet, you have anExamination Response Form. Follow the directions on the front of theResponse Form.

3. Disqualification from the examination will result if you bring books, paper,

notes or unauthorized electronic devices into the examination room.

4. All multiple-choice answers must be entered on the Response Form using anHB pencil. Multiple-choice answers entered in this examination booklet willnot be marked.

5. For each of the written-response questions, write your answer in ink in thespace provided in this booklet.

6. When instructed to open this booklet, check the numbering of the pages toensure that they are numbered in sequence from page one to the last page,which is identified by

ENDOFEXAMINATION .

7. At the end of the examination, place your Response Form inside the frontcover of this booklet and return the booklet and your Response Form to thesupervisor.

1999 Ministry of Education


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THIS PAGE INTENTIONALLY BLANK


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BIOLOGY 12 PROVINCIAL EXAMINATION

Value SuggestedTime

1. This examination consists oftwo parts:

PART A: 50 multiple-choice questions 50 45

PART B: 10 written-response questions 50 75

Total: 100 marks 120 minutes

2. Electronic devices, including dictionaries and pagers, are not permitted in the examination room.

3. The time allotted for this examination is two hours.


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OVER- 1 -

PART A: MULTIPLE CHOICE

Value: 50 marks Suggested Time: 45 minutes

INSTRUCTIONS: For each question, select the best answer and record your choice on the ResponseForm provided. Using an HB pencil, completely fill in the circle that has the lettercorresponding to your answer.

1. Which of the following organelles is correctly matched with its product?

A. nucleolus DNA

B. mitochondria ATP

C. Golgi apparatus lipid

D. smooth endoplasmic reticulum protein

2. Which of the following organelles breaks down dead cells?

A. nucleus

B. lysosome

C. Golgi apparatus

D. rough endoplasmic reticulum


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Use the following diagram to answer questions 3 and 4.

X Y

3. The structure labelled X is composed mostly of

A. glycogen and protein.

B. nucleic acid and glycogen.

C. protein and phospholipids.

D. nucleic acid and phospholipids.

4. One function of the structure labelled Y is to

A. replicate DNA.

B. control cell division.

C. digest food molecules.

D. produce digestive enzymes.


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OVER- 3 -

5. A substance which helps maintain a constant pH in a solution is a(n)

A. salt.

B. acid.

C. base.

D. buffer.

Use the following diagram to answer question 6.

H H

H N C C

H

O

OH H

H

N C C OH

H H

H2O

O

6. The diagram illustrates a step in the

A. hydrolysis of a protein.

B. synthesis of an enzyme.

C. production of nucleic acid.

D. conversion of glucose molecules to starch.

________________________________________________

7. The building blocks or monomers that make up carbohydrates are

A. nucleotides.

B. amino acids.

C. monosaccharides.

D. fatty acids and glycerol.

8. Compared to saturated fats, unsaturated fats contain less

A. oxygen.

B. glycerol.

C. hydrogen.

D. fatty acids.


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9. The number of adenine bases in a DNA molecule equals the number of thymine bases because

A. DNA contains equal numbers of all four bases.

B. thymine always follows adenine on each DNA strand.

C. DNA is made of alternating adenine and thymine bases.

D. adenine on one strand bonds to thymine on the other strand.

10. The product of transcription is

A. DNA.

B. protein.

C. mRNA.

D. a ribosome.

11. Which of the following molecules is a building block or monomer of RNA?

A. CH2OH

C

H

C

H

OH

C

OH

O

C

C

H

OH

H

H

OH

B.

CH

CH2

CH2

O

O

OC

C

C

O

O

O

CH3 CH2( )16

CH3 CH2( )16

CH3 CH2( )16

C. H H

N C CH

H

O

OH

D.

PN

N


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OVER- 5 -

Use the following chart to answer question 12.

Three-letter codons of messenger RNA, and the amino acids specified by the codons

AAUAAC

AAAAAG

Asparagine

Lysine

CAUCAC

CAACAG

Histidine

Glutamine

GAUGAC

GAAGAG

Asparatic acid

Glutamic acid

UAUUAC

UAAUAG

Tyrosine

Stop

AGUAGC

AGAAGG

Serine

Arginine

UGUUGC

UGAUGG

Cysteine

StopTryptophan

AUUAUC

AUA

AUG

Isoleucine

Methionine

UUUUUC

UUAUUG

Phenylalanine

Leucine

ACUACCACAACG

Threonine

CCUCCCCCACCG

Proline

GCUGCCGCAGCG

Alanine

UCUUCCUCAUCG

Serine

CGUCGCCGACGG

Arginine

GGUGGCGGAGGG

Glycine

CUUCUCCUACUG

Leucine

GUUGUCGUAGUG

Valine

12. A strand of DNA has the following bases:

C A C G G C C

If the adenine base was deleted, which amino acids would be coded for?

A. valine, proline

B. glycine, alanineC. proline, arginine

D. glycine, arginine

________________________________________________

13. The process by which new blood vessels supply a growing tumour is

A. metastasis.

B. promotion.

C. malignancy.

D. vascularization.


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14. Which of the following is capable of changing a proto-oncogene into an oncogene?

A. virus

B. antibody

C. bacterium

D. lymphocyte

15. An experiment was carried out to study the carcinogenic effects of certain chemicals on mice.

Similar amounts of these chemicals were applied to their skins over a 6-month period. The

results are shown below.

CHEMICAL X CHEMICAL YCHEMICALS

X AND YCONTROL

(NO TREATMENT)

18% developedskin tumours




Given the results, which of the following statements is correct?

A. Chemical Y is a promoter.

B. Chemical X can act only as a promoter.

C. Chemical Y can act only as an initiator.

D. Neither X nor Y is an initiator or a promoter.

16. Molecules in the cell membrane that function as receptors are

A. proteins.

B. glycerol.

C. cholesterol.

D. phospholipids.


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OVER- 7 -

Use the following diagrams to answer question 17.

Cl

starchglucose

Na+

protein

H2O

Initial

SelectivelyPermeableMembrane

Cl

glucose

Na+

H2O H2O

Two hours later

starch

Cl

Na+

protein

glucose Cl

starch

H2O

Na+

protein

glucose

SelectivelyPermeableMembrane

protein

starch

17. The diagrams illustrate that the membrane selects according to the

A. size of the molecules.

B. temperature of the solution.

C. concentration of the molecules.

D. electronic charge of the molecules.


18. The diagram shows a white blood cell ingesting a bacterium. The bacterium enters the white

blood cell by

A. diffusion.

B. pinocytosis.

C. phagocytosis.

D. active transport.


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19. Enzymes function to increase the rate of a metabolic reaction by

A. denaturing the substrate.

B. adding energy to the reaction.

C. decreasing the energy of activation.

D. increasing the concentration of the reactants.

Use the following graphs to answer question 20.

X

Graph 2

Amountof

Product

(mg)

Amountof

Product

(mg)

Time (minutes)

Graph 1

0 15 30 0 15 30

Time (minutes)

20. Graph 1 represents the rate of reaction between lipase and its substrate. In graph 2, what

occurred at time X that caused the change in the reaction?

A. Fat was added.

B. The pH was changed from 5 to 8.

C. A competitive inhibitor was added.

D. The temperature of the reaction was raised to 100C .


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Y

Z

X

W

21. The structure labelled X releases a substance after the ingestion of

A. fat.

B. starch.

C. protein.

D. carbohydrate.

22. Digestion of peptides and absorption of their products occurs in which of the structures?

A. W

B. X

C. Y

D. Z


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23. The reaction shown below is catalyzed by secretions from which organs?

protein + H2O peptides

A. pancreas and liver

B. liver and duodenum

C. stomach and pancreas

D. duodenum and stomach

24. Increasing the secretion of insulin would have which of the following effects?

A. decreased blood sugar

B. decreased metabolic rate

C. increased protein synthesis

D. increased digestion of carbohydrate

25. High levels of toxins in the blood may indicate a problem with the function of the

A. liver.

B. stomach.

C. pancreas.

D. small intestine.

Use the following characteristics to answer question 26.

one-way valves thin elastic layer near skeletal muscle

26. The characteristics above describe which type of vessel?

A. vein

B. artery

C. arteriole

D. capillary


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X

27. The structure labelled X is the

A. iliac vein.

B. renal vein.

C. subclavian vein.

D. posterior vena cava.


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W

X

Y

Z

28. Which letter indicates a portal vein?

A. W

B. X

C. Y

D. Z

________________________________________________

29. Oxygen is delivered to the heart muscle by the

A. aorta.

B. carotid artery.

C. coronary artery.D. pulmonary artery.


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30. A persons blood pressure was measured at five blood vessels and plotted on the graph below.

Heart

BloodPressure

(mm of Hg)

HeartTissuesX

The reading taken at X would be at the

A. renal artery.

B. pulmonary vein.

C. posterior vena cava.

D. peritubular capillaries.


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X

31. In the fetus, the function of the structure labelled X is to

A. take blood to the lungs.

B. ensure adequate blood flow to the brain.

C. return blood from the placenta to the heart.

D. direct some of the blood away from the lungs.

________________________________________________

32. Blood capillaries and lymph capillaries both

A. filter bacteria.

B. have one-way valves.

C. contain red blood cells.

D. have walls which are one-cell thick.


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Use the following information to answer question 33.

transport gases maintain body temperature protect the body against blood loss produce hormones that stimulate metabolism carry digestive enzymes to the small intestine

33. How many of the above are functions of the blood?

A. two

B. three

C. four

D. five

________________________________________________

34. Which of the following correctly matches structure with function?

A. platelets provide immunity

B. plasma proteins carry oxygen

C. red blood cells carry carbon dioxide

D. white blood cells initiate blood clotting


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Use the following graph to answer question 35.

4 8

Weeks of Starvation

Quantity ofNutrients Stored

in Body

Nutrient Use During Starvation

carbohydrates in cells

stored fats

plasma proteins

0

35. The graph illustrates how the body consumes stored nutrients during a prolonged period of

starvation. After eight weeks,

A. blood pressure will increase.

B. fluids will accumulate in tissues.

C. glycogen production will increase.

D. hemoglobin will not release oxygen.


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OVER- 17 -


Z

X

Y

W

36. Which area indicated in the diagram is the location of the AV node?

A. W

B. X

C. Y

D. Z


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X


A. larynx.

B. trachea.

C. bronchus.

D. diaphragm.

________________________________________________

38. Inhalation is caused by

A. the diaphragm moving up and the ribs moving in.

B. the diaphragm moving up and the ribs moving out.

C. the diaphragm moving down and the ribs moving in.

D. the diaphragm moving down and the ribs moving out.


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OVER- 19 -


10

20

30

0

AverageBreathing Rate

(breaths per minute)

Time

39. Which of the following would cause the effect shown?

A. increased oxygen in the blood

B. increased numbers of red blood cells

C. increased carbon dioxide in the blood

D. decreased concentration of hydrogen ions

________________________________________________

40. The exchange of oxygen and carbon dioxide in external respiration occurs by

A. osmosis.

B. diffusion.

C. active transport.

D. facilitated diffusion.

41. Which of the following reactions occurs in a capillary of the leg?

A. Hb + H+ HHb

B. HbCO2 Hb + CO2C. Hb + oxygen HbO2D. H+ + HCO3

H2CO3


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Y

X

WZ

6

74

84

V

42. The structure labelled X is a(n)

A. node.

B. axon.

C. synapse.

D. dendrite.

43. If an impulse started at V, it would travel to

A. Wand X.

B. W and Z.C. X and Z.

D. Y and Z.


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OVER- 21 -


X

Y

44. If molecule X causes depolarization at Y, what could X be?

A. sodium ions

B. calcium ions

C. acetylcholine

D. acetylcholinesterase

________________________________________________

45. Which of the following is a true statement about the sympathetic and parasympathetic nervous

systems?

A. Sympathetic system causes increased rates of digestion while the parasympathetic systemcauses decreased rates of digestion.

B. Sympathetic system causes decreased breathing rate while the parasympathetic system causesincreased breathing rate.

C. Sympathetic system causes constriction of the iris while the parasympathetic system causesdilation of the iris.

D. Sympathetic system causes increased heart rate while the parasympathetic system decreasesheart rate.


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W

X

Y

Z

46. At which location would the greatest concentration of glucose be found?

A. W

B. X

C. Y

D. Z

________________________________________________

47. The inability to regulate the concentration of sodium ions in the blood could be due to improper

functioning of the

A. adrenal cortex, since it produces ADH.

B. adrenal cortex, since it produces aldosterone.

C. adrenal medulla, since it produces ADH.

D. adrenal medulla, since it produces aldosterone.


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OVER- 23 -

48. Increased secretion of FSH (follicle-stimulating hormone) will result in increased production of

A. sperm.

B. progesterone.

C. seminal fluid.

D. human chorionic gonadotropin (HCG).

49. The part of a sperm cell containing the greatest number of mitochondria is the

A. head.

B. flagellum.

C. acrosome.

D. mid-piece.


Y

X

W

Z

50. In which area does fertilization normally occur?

A. WB. X

C. Y

D. Z

This is the end of the multiple-choice section.Answer the remaining questions directly in this examination booklet.


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PART B: WRITTEN RESPONSE


INSTRUCTIONS: 1. Use a pen for this part of the examination.

2. Write your answers in the space below the questions.

3. Organization and planning space has been incorporated into the space allowed

for answering each question.

4. You may not need all of the space provided to answer each question.


CH2OH

C

H

C

H

OH

C

OH

O

C

C

H

OH

H

H

OH

1. a) Identify the molecule above. (1 mark)

b) What is the general term given to polymers formed from this molecule? (1 mark)

c) List two biological functions of these polymers. (2 marks)

i)

ii)


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2. Using the table below, list three differences between RNA and DNA.

(3 marks: 1 mark for each contrasting pair)

RNA DNA


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outside inside

membrane

Na+

Na+P

P

Na+

Na+Na+

Na+Na+

Na+

Na+

P P

P P P

X

3. a) Identify the process shown in the diagram above. (1 mark)

b) Give one example in which this process is used in the body. (1 mark)

c) Describe the function of the molecule represented by P P P : (1 mark)

d) What is the function of molecule X? (1 mark)


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O

2 glucose molecules

Y

X

4. a) The diagrams illustrate a reaction that occurs in the small intestine. Give the specific name

for each of the following.

Molecule X: (1 mark)

Molecule Y: (1 mark)

b) In a laboratory experiment, substance Y was added in increasing amounts until it eventually

had no effect on the rate of the reaction. Explain why. (1 mark)

c) A solution containing lead ions was added to the reaction. How will the addition of this

solution affect the reaction? Explain why. (2 marks)


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Z

X

Y

5. a) State two functions of structure Z. (2 marks)

i)

ii)


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b) For each of the following structures, list one enzyme it secretes and the substrate that

the enzyme acts upon. (4 marks: 1 mark each for enzyme; 1 mark each for substrate)

Structure X:

Enzyme:

Substrate:

Structure Y:

Enzyme:

Substrate:


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6. Describe how the structure of each of the following aids in its function. (3 marks)

Artery:

Semi-lunar valve:

Capillary:

7. Identify three substances transported by hemoglobin in the blood and give the name of each

form of hemoglobin. (3 marks: 12

mark each)

SUBSTANCE TRANSPORTED FORM OF HEMOGLOBIN


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X Y

8. Describe, in correct order, the events that occur during the transmission of a nerve impulse

from point X to point Y. (8 marks)


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W

Y

Z

X

9. Identify the following structures and give a different function of each structure.

(8 marks: 1 mark each for name; 1 mark each for function)

Structure W:

Name:

Function:

Structure X:

Name:

Function:


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Structure Y:

Name:

Function:

Structure Z:

Name:

Function:


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10. a) Give two functions of each of the following hormones.

Estrogen: (2 marks)

i)

ii)

LH (luteinizing hormone): (2 marks)

i)

ii)

b) Describe two hormonal changes that occur in the mother as a result of implantation.

(2 marks)

i)

ii)

END OF EXAMINATION


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BIOLOGY 12

August 1999

Course Code = BI


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FOR OFFICE USE ONLY

BIOLOGY 12

August 1999

Course Code = BI

Score forQuestion 1:

1. _____(4)


2. _____(3)


3. _____

(4)


4. _____(5)

Score for

Question 5:

5. _____(6)


6. _____(3)


7. _____(3)


8. _____(8)


9. _____(8)


10. _____

(6)


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JUNE 1999



BIOLOGY 12









ENDOFEXAMINATION .




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Value SuggestedTime






3. The time allotted for this examination is two hours.


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X

1. The structure labelled X is a(n)

A. vacuole.

B. Golgi body.

C. mitochondrion.

D. endoplasmic reticulum.

________________________________________________

2. During the metamorphosis from tadpole to frog, which of the following organelles would cause

the cells of the tail of a tadpole to be broken down and digested?

A. ribosomes

B. lysosomes

C. Golgi bodies

D. endoplasmic reticulum

3. Two functions of rough endoplasmic reticulum are to

A. detoxify and transport drugs.

B. modify and activate hormones.

C. synthesize and transport enzymes.

D. join with and hydrolyze food vacuoles.


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4. In which of the following is the greatest amount of deoxyribonucleic acid (DNA) found?

A. nucleus

B. ribosome

C. nucleolus

D. nuclear envelope

5. If the pH of a solution changes from 2 to 5, then the solution has

A. become a base.

B. lost hydrogen ions.

C. become more acidic.

D. gained hydrogen ions.

6. The process that joins amino acids together to make enzymes is

A. oxidation.

B. hydrolysis.

C. denaturation.

D. dehydration synthesis.

7. Most of the cell membrane is made from

A. steroids.

B. proteins.

C. phospholipids.D. polysaccharides.


C C N C C N C C N C C N

H

H O

H H O

H H O

H H O

HH

H

H

H

8. The molecule shown above is part of

A. ATP.

B. DNA.

C. a steroid.

D. an enzyme.


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OVER- 3 -


OO

O

CH2

O

CH2

OOO

O O O O

O

CH2

OO

O

OO

O OO

OO

OO

O

OO

O

O

OO

O

CH2

O

9. The diagram shows a molecule that is found in the

A. liver.

B. blood.C. pancreas.

D. gall bladder.

________________________________________________

10. How many double bonds are there between carbon atoms in a saturated fatty acid?

A. 0

B. 1

C. 2D. more than 2

11. Which of the following types of bonding occurs during complementary base pairing?

A. ionic

B. peptide

C. covalent

D. hydrogen


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12. A polypeptide found in the cytoplasm of a cell contains 12 amino acids. How many

nucleotides would be required in the mRNA for this polypeptide to be translated?

A. 4

B. 12

C. 24

D. 36

13. A biologist determined the surface area and volume of four cells: two flat cells with the same

thickness and two spherical cells. Which of the four cells would have the greatest surface area

to volume ratio?

A. The small, flat cell with a volume of 5 microlitres.

B. The small, spherical cell with a volume of 5 microlitres.

C. The large, flat cell with a volume of 10 microlitres.

D. The large, spherical cell with a volume of 10 microlitres.

14. An increase in thyroxin will have which of the following effects?

A. increased CO2 production

B. increased glycogen production

C. decreased rate of ATP production

D. decreased rate of glucose metabolism


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V

W

X

Y

Z

15. Hydrolysis of peptide bonds found in food occurs in

A. V and Z.

B. W and Y.

C. X and V.

D. X and Z.


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1 2 3 4 5 6 7 8 9

Enzyme X Enzyme Y

EnzymeActivity

pH

0

16. The graph shows the activity of two different enzymes in the digestive tract that have the same

substrate. What is enzyme Y?

A. pepsin

B. trypsin

C. amylase

D. peptidase


colon pancreas gall bladder small intestine salivary glands

17. How many of the structures above produce enzymes that digest carbohydrates?

A. two

B. three

C. four

D. five


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18. The chemical digestion of fats is a result of the release of secretions from the

A. pancreas.

B. gall bladder.

C. small intestine.

D. salivary glands.


Fat Fat droplets

19. Secretions from which of the following would have the effect shown in the diagram?

A. liver

B. mouth

C. stomach

D. large intestine

________________________________________________

20. Which of the following is not a function of the liver?

A. production of urea

B. synthesis of plasma proteins

C. secretion of digestive enzymes

D. regulation of blood glucose levels


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21. The structure above is found lining the walls of the

A. colon.

B. stomach.

C. esophagus.D. small intestine.


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OVER- 9 -


W

X

Y

Z

22. Which letter indicates the carotid artery?

A. W

B. X

C. Y

D. Z


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BLOODVESSEL

PRESSURE(mm of mercury)

VELOCITY(cm/sec.)

S less than 5 15

T 20 80

U 10 2

V 40 100

23. Blood vessel U is a(n)

A. vein.

B. artery.

C. venule.

D. capillary.


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OVER- 11 -


X

24. The blood vessel found in adults that contains oxygen levels similar to the blood vessel

labelled X is the

A. renal vein.

B. pulmonary vein.

C. pulmonary artery.

D. hepatic portal vein.


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25. A red blood cell is located in an artery in your right arm. How many capillary beds must this

cell pass through before it is returned to the left ventricle?

A. one

B. two

C. three

D. four

26. The function of the nodes in the lymphatic system is to

A. filter debris.

B. produce platelets for clotting.

C. break down worn-out red blood cells.

D. help maintain a constant blood pressure.

27. What occurs when an antigen enters the body?

A. There is increased platelet production.

B. Red blood cells phagocytize the antigen.

C. Antibodies change shape to fit the antigen.

D. Specific antibodies are produced and released.

28. An irregular heartbeat where contraction of the atria does not always result in contraction of

the ventricles, likely indicates a problem with the

A. SA node.B. AV node.

C. AV valve.

D. semi-lunar valve.

29. An increase in which of the following would cause hypotension?

A. heart rate

B. cardiac output

C. arteriole dilationD. reabsorption of water by the kidneys


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30. What happens during atrial diastole?

A. Atria fill with blood.

B. Semi-lunar valves close.

C. Ventricles fill with blood.

D. Atrioventricular valves open.

31. What is the correct sequence of structures through which an oxygen molecule passes from the

nostrils to the alveolus?

A. larynx, right bronchus, trachea, bronchioles

B. right bronchus, larynx, bronchioles, trachea

C. larynx, trachea, right bronchus, bronchioles

D. trachea, larynx, bronchioles, right bronchus

32. Mucus is moved along the respiratory tract by

A. cilia.

B. flagella.

C. peristalsis.

D. active transport.

33. Which of the following would cause a decrease in the pH of the blood during internal

respiration?

A. running for ten minutesB. digestion of an acidic food

C. taking in several deep breaths

D. prolonged period of inactivity

34. Most of the carbon dioxide produced by tissues is carried back to the lungs as

A. bicarbonate ions.

B. reduced hemoglobin.

C. carbaminohemoglobin.D. a gas dissolved in plasma.


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35. The part of a sensory neuron that transmits nerve impulses from a receptor to the cell body

is the

A. axon.

B. synapse.

C. dendrite.

D. neurotransmitter.


X

36. The molecules labelled X function to

A. open sodium ion gates.

B. speed up the transmission of impulses.

C. provide an energy source for the resting potential.

D. tell the brain the kind of stimulus that is being received.

________________________________________________

37. The parasympathetic nervous system

A. controls the central nervous system.

B. lowers blood pressure and promotes digestion.

C. uses noradrenalin as the neurotransmitter at synapses.

D. initiates the fight or flight response in times of stress.


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OVER- 15 -

38. How does the hypothalamus increase the metabolic rate of cells in the body?

A. It produces and releases thyroxin.

B. It secretes a specific releasing hormone.

C. It increases autonomic nerve stimulation.

D. It causes cells to become permeable to blood glucose.


39. Which of the following is not a function of the organ shown?

A. to produce urea

B. to excrete metabolic wastes

C. to regulate the acidity of the bloodD. to maintain a constant blood volume

________________________________________________

40. Filtrate enters the Bowmans capsule by

A. active transport.

B. tubular excretion.

C. pressure filtration.

D. selective reabsorption.


62/575

- 16 -

41. Which of the following occurs in the distal tubule to return acidic blood back to a normal pH?

A. Both sodium and hydrogen ions are excreted.

B. Bicarbonate ions are excreted and hydrogen ions are reabsorbed.

C. Ammonia and hydrogen ions are excreted and sodium ions are reabsorbed.

D. Ammonia and hydrogen ions are reabsorbed and bicarbonate ions are excreted.


Z

Y

X

W

42. Which letter indicates the seminal vesicle?

A. W

B. X

C. Y

D. Z

________________________________________________

43. The duct that is used by both the reproductive and excretory systems in males is the

A. ureter.B. urethra.

C. renal pelvis.

D. vas deferens.


63/575

OVER- 17 -

44. Testosterone is produced in the

A. epididymis.

B. interstitial cells.

C. seminal vesicles.

D. seminiferous tubules.

45. The part of the sperm that contains hydrolytic enzymes is the

A. tail.

B. nucleus.

C. acrosome.

D. mid-piece.


X


A. uterus.B. cervix.

C. follicle.

D. oviduct.


64/575

- 18 -

47. The function of the endometrium is to

A. carry the egg to the uterus.

B. release an egg once a month.

C. produce hormones for the uterine cycle.

D. provide nourishment for the developing embryo.

48. A rise in blood levels of FSH at the beginning of the ovarian cycle causes

A. menopause.

B. the release of the egg.

C. the maturation of the follicle.

D. the breakdown of the endometrium.

49. Low levels of estrogen and progesterone in the blood will result in

A. fertilization.

B. no ovulation.

C. menstruation.

D. destruction of the corpus luteum.

50. Which of the following, if present in urine samples, would indicate pregnancy?

A. estrogen

B. progesterone

C. luteinizing hormone (LH)D. human chorionic gonadotropin (HCG)



65/575

OVER- 19 -








1. a) Define recombinant DNA. (1 mark)

b) Describe two uses for recombinant DNA. (2 marks)

i)

ii)


66/575

- 20 -

2. Give the purpose of each of the following steps in the process of protein synthesis.

a) Ribosome moving along a mRNA: (1 mark)

b) Adenine bonding to thymine: (1 mark)

c) An amino acid bonding to a specific tRNA: (1 mark)

d) Forming of peptide bonds: (1 mark)


67/575

OVER- 21 -


Side View

Top View Top View

Tissue Sample A Tissue Sample B

Side View

3. a) The diagrams above were made from samples of epithelial cells taken from healthy tissue

and cancerous tissue. Which tissue sample is from the cancerous tissue? (1 mark)

b) Give two reasons for your answer in a) above. (2 marks)

i)

ii)


68/575

- 22 -

4. An experiment was conducted to determine the concentration of molecules in the cytoplasm of

potato cells. The following steps were taken:

1. Five different sugar solutions were added to five numbered test tubes as shown

in the data table below.

2. Five potato discs (cut from the same potato) were weighed and one disc was added to

each test tube.

3. After 24 hours, the potato discs were removed, blotted dry, and weighed again.

3 10.0 5.2 5.5 6+

TESTTUBE

CONCENTRATIONOF SUGARSOLUTION

(%)

INITIALPOTATO MASS

(grams)

FINALPOTATO MASS

(grams)

CHANGEIN MASS

(%)

1 30.0 5.0 4.0 20

2 20.0 4.8 4.3 10

4 5.0 4.7 5.4 15+

5 5.1 6.1 20+(distilled water only)

0.0

a) Name and describe the process that allowed the potato cells to gain and lose mass when

placed in the sugar solutions. (2 marks: 1 mark for name; 1 mark for description)

Name of Process:

Description of Process:

b) Explain the change in mass of the potato disc in test tube 1. (2 marks)


69/575

OVER- 23 -

c) Draw a graph that compares the concentration of sugar solution (%) to the change in

mass (%) of the potato discs. Label the x-axis as the concentration of sugar solution (%).

(2 marks)

0

d) Use your graph to determine the concentration of sugar solution (%) that would be isotonic

to the cytoplasm of the potato cells. (1 mark)


70/575

- 24 -

5. An experiment was conducted to measure the effect of temperature on an enzyme isolated from

the small intestine. Data was collected and graphed as shown below.

Activity Rate for Enzyme(amount of product)

(mg/min)

Temperature (C)

10 20 30 40 50 600

5

10

15

20

25

30

0

Explain why the following temperatures change the activity rate of the enzyme.

0C to 35C: (1 mark)

37C: (1 mark)

45C to 55C: (2 marks)


71/575

OVER- 25 -

6. The following substances were isolated from organs found in the digestive system. Name

the organ in which each substance was produced and give one function of the substance.

(4 marks)

pepsin

nuclease

SUBSTANCE FUNCTIONORGAN WHERE

PRODUCED


72/575

- 26 -

7. a) Describe one function of each of the following. (3 marks)

Red blood cells:

White blood cells:

Platelets:

b) Where are red blood cells produced? (1 mark)


73/575

OVER- 27 -

8. Describe the interaction of the lungs, pleural membranes, ribs, and diaphragm during

inhalation. (4 marks)


74/575

- 28 -

9. Explain how an action potential is generated in a neuron. (4 marks)


75/575

OVER- 29 -


X

Z

Y

10. Identify structures X, Y and Z and give one function of each.(6 marks: 1 mark each for name; 1 mark each for function)

Structure X:

Name:

Function:

Structure Y:

Name:

Function:

Structure Z:

Name:

Function:


76/575

- 30 -

11. a) Using the following diagram, label the parts of a nephron in the blanks provided.

(3 marks: 12

mark each)

b) Identify one hormone that responds to a decrease in blood volume and explain how

this hormone functions to return blood volume to normal levels.(4 marks: 1 mark for name; 3 marks for explanation)

Name:

Explanation:

END OF EXAMINATION


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|||||||||||||

|||||||||||


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BIOLOGY 12

June 1999

Course Code = BI


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FOR OFFICE USE ONLY

BIOLOGY 12

June 1999

Course Code = BI


1. _____(3)


2. _____(4)


3. _____

(3)


4. _____(7)

Score for

Question 5:

5. _____(4)


6. _____(4)


7. _____(4)


8. _____(4)


9. _____(4)


10. _____

(6)


11. _____(7)


80/575



NOVEMBER 1999



BIOLOGY 12









ENDOFEXAMINATION .




81/575



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Value SuggestedTime






3. Ensure that you use language and content appropriate to the purpose and audience of this

examination. Failure to comply may result in your paper being awarded a zero.

4. This examination is designed to be completed in two hours. Students may, however, take up to

30 minutes of additional time to finish.


83/575



84/575

OVER- 1 -




1. Which organelle contains enzymes that digest old cells?

A. nucleus

B. ribosome

C. lysosome

D. Golgi body


X

2. The organelle labelled X

A. makes ATP.

B. synthesizes proteins.

C. packages and modifies proteins.

D. controls what enters and leaves the cell.


85/575

- 2 -


X


A. nucleolus.B. mitochondria.

C. cell membrane.

D. rough endoplasmic reticulum.


4. Products of this organelle are needed for which of the following?

A. capillary-tissue fluid exchange

B. diffusion of oxygen into the lung capillariesC. re-establishment of the resting potential in a neuron

D. movement of water into a cell across a semi-permeable membrane


86/575

OVER- 3 -

5. Which organelles are found in greater amounts in a cell that produces enzymes for the digestion

of starches?

A. Golgi bodies and nuclei

B. lysosomes and smooth endoplasmic reticulum

C. Golgi bodies and rough endoplasmic reticulum

D. smooth endoplasmic reticulum and mitochondria

6. A glucose molecule contains

A. six carbon atoms.

B. two high-energy phosphates.

C. three fatty acids and glycerol.

D. a long chain of carbohydrate rings.


Substance DSubstance D

Substance A

Substance C

7. The diagram above represents a series of reactions which occur in the body. Ifsubstance D

was unavailable, which of the following would result?

A. DNA could not be replicated.

B. Proteins would not be produced.

C. Carbohydrates could not be hydrolyzed.

D. Fatty acids and glycerol would not join together to produce fats.


87/575

- 4 -

8. A characteristic of unsaturated fats is that they

A. denature as they cool.

B. are made up of glucose and fructose.

C. are made up of amino acids and glycerol.

D. have double bonds in their carbon chains.

9. The level of protein structure represented by the alpha-helix shape is

A. primary.

B. secondary.

C. tertiary.

D. quaternary.


mRNA

SP

P

PP

P

P

P

P

P P

P

P

P

PP

P

P

P

P

P

P

P

P

P

P

P

P

PS

S

SS

S

S

S

S

S

S

S

S

S

S

S

S

S

S

S

S

S

S S

S

S

S

S

S

S

S

S

S

S

P

10. Which process is shown above?

A. translation

B. elongation

C. replication

D. transcription


88/575

OVER- 5 -

11. A change in the sequence of bases in a strand of DNA that occurs as a result of exposure to

x-rays is an example of

A. mutation.

B. denaturation.

C. transcription.

D. protein synthesis.

12. A proto-oncogene is described as DNA that

A. causes cancer.

B. causes the vascularization of a tumour.

C. can be mutated into cancer-causing DNA.

D. directly causes uncontrolled cellular growth.

13. Carrier molecules that bring materials into cells are

A. lipids.

B. proteins.

C. glycogen.

D. phospholipids.

14. Which of the following moves material against a concentration gradient?

A. osmosis

B. diffusionC. active transport

D. facilitated transport

15. The secretion of noradrenalin into the synaptic cleft occurs by which of the following

processes?

A. exocytosis

B. pinocytosis

C. endocytosisD. active transport


89/575

- 6 -


Membrane permeableto small molecules

After 10 minutes

Membrane permeableto small molecules

SideA SideB

Initial Conditions

SideA SideB

16. Which of the following conditions would cause the change in the fluid levels as shown after 10minutes?

SOLUTION INSIDE A

SOLUTION INSIDE B

A. distilled water 5% salt

B. 2% glucose 5% glucose

C. 5% protein 2% protein

D. 2% salt 2% salt


X

17. The diagram above represents an enzyme-catalyzed reaction. The substance labelled X is mostlikely a

A. steroid.

B. protein.

C. vitamin.

D. calcium ion (Ca2+ ).


90/575

OVER- 7 -

18. A function of enzymes is to

A. emulsify fats.

B. carry information to nerves.

C. catalyze chemical reactions.

D. maintain constant blood pH.

19. What would occur if sodium bicarbonate ions were removed from pancreatic juice?

A. Decreased amounts of bile would be released.

B. Increased H2O absorption would occur in the colon.

C. The cells lining the small intestine would be damaged.

D. Digestion of nutrients in the small intestine would increase.

20. Which of the following describes peristalsis?

A. the physical breakdown of fats

B. production of vitamins byE. coli

C. release of enzymes by the pancreas

D. muscle contractions of the digestive tract

21. Trypsin functions best in which of the following conditions?

A. basic

B. acidic

C. neutralD. low pH


91/575

- 8 -


X

22. The absorption of materials at structure X is temporarily impaired. What would occur during

the time that structure X is not functioning properly?

A. Absorption of fats would stop.

B. The amount of glycogen produced in the liver would decrease.

C. The pancreas would release more enzymes and bicarbonate ions.

D. Pepsinogen would be secreted by the stomach in greater amounts.

________________________________________________

23. Which type of blood vessel has thick walls in order to withstand high pressure?

A. vein

B. artery

C. arteriole

D. capillary

24. The blood vessels that carry blood to and from the head are the

A. iliac arteries and veins.

B. subclavian arteries and veins.

C. carotid arteries and jugular veins.

D. anterior (superior) and posterior (inferior) vena cavae.


92/575

OVER- 9 -


25. The structure above would carry

A. deoxygenated blood from the legs to the heart.

B. deoxygenated blood from the heart to the lungs.

C. oxygenated blood toward and away from the glomerulus.

D. deoxygenated blood from the left atrium to the left ventricle.

________________________________________________

26. Which of the following would occur as a result of the oval opening in the heart remaining openafter birth?

A. Blood pressure in the lungs would increase.

B. Impulses from the sinoatrial (SA) node would stop.

C. Blood in the right atrium would mix with blood in the left atrium.

D. A greater amount of blood would flow into the pulmonary system.

27. Which of the following is a function of red blood cells?

A. clot blood

B. carry oxygen

C. fight infection

D. regulate osmotic pressure


93/575

- 10 -


28. Which of the following would result if the cells above were functioning properly?

A. Blood clotting would occur.

B. Less oxygen would be carried in the blood.

C. Disease-causing bacteria could be engulfed.

D. Fluids would remain in the tissues, causing swelling.

________________________________________________

29. Which chamber of the heart pumps oxygenated blood into the aorta?

A. left atrium

B. right atrium

C. left ventricle

D. right ventricle


94/575

OVER- 11 -


X

30. The structure labelled X is a

A. trachea.

B. bronchus.

C. bronchiole.

D. diaphragm.

________________________________________________

31. Where does oxygen diffuse into the blood?

A. alveoli

B. trachea

C. bronchioles

D. pleural membranes

32. An increase in the rate of contractions of the diaphragm and rib muscles would indicate

A. decreased hydrogen ion concentration.

B. decreased reduced hemoglobin in the blood.

C. increased concentration of bicarbonate ion in the blood.

D. increased concentration of oxyhemoglobin in the blood.


95/575

- 12 -

33. Blood entering the systemic circulation carries high concentrations of

A. oxyhemoglobin.

B. bicarbonate ions.

C. reduced hemoglobin.

D. carbaminohemoglobin.


X


A. axon.

B. dendrite.

C. cell body.

D. myelin sheath.


35. The structure above carries impulses

A. from a receptor.

B. to a muscle or a gland.

C. away from the central nervous system.D. solely within the central nervous system.


96/575

OVER- 13 -

36. Which of the following is a characteristic of a resting potential?

A. secretion of calcium ions

B. neurotransmitters move into the axon

C. depolarization of the post-synaptic membrane

D. a net negative charge on the inside of the axon


X


A. cerebrum.

B. cerebellum.

C. hypothalamus.

D. corpus callosum.


97/575

- 14 -


X

38. If a neuron is severed at point X,

A. sensory impulses still reach the brain.

B. increased amounts of neurotransmitters are secreted.

C. a message is sent to the sensory receptors, inhibiting them.

D. another interneuron moves into place to complete the reflex arc.


X

39. If the structure above is part of a reflex arc, the part labelled X would receive messages

directly from

A. a receptor.

B. an interneuron.

C. a motor neuron.

D. a muscle or gland.


98/575

OVER- 15 -

40. Which of the following is controlled by the somatic nervous system?

A. rate of heartbeat

B. contraction of skeletal muscles

C. increased blood flow to muscle tissue

D. movement of food through the intestines

41. The part of the brain responsible for muscle coordination is the

A. cerebellum.

B. hypothalamus.

C. corpus callosum.

D. medulla oblongata.

42. Which structure carries urine from the bladder to the outside of the body?

A. ureterB. urethra

C. renal pelvis

D. collecting duct

43. Which substance is found in the glomerulus, Bowmans capsule and efferent arteriole but is not

normally found in the collecting duct?

A. urea

B. glucoseC. penicillin

D. sodium ions

44. Blood is brought to the glomerulus by the

A. renal vein.

B. afferent arteriole.

C. efferent arteriole.

D. peritubular capillaries.

45. The source of antidiuretic hormone (ADH) is the

A. thyroid.

B. adrenal cortex.

C. anterior pituitary.

D. posterior pituitary.


99/575

- 16 -

46. Storage and maturation of sperm occurs in the

A. epididymis.

B. corpus luteum.

C. seminal vesicle.

D. Cowpers gland.

47. When sperm is ejaculated, it comes into contact with or passes near each of the following

structures. Which sequence correctly describes the passage of sperm out of the body?

A. seminiferous tubules prostate vas deferens urethra

B. seminiferous tubules vas deferens urethra prostate

C. seminiferous tubules vas deferens prostate urethra

D. prostate seminiferous tubules vas deferens urethra


Time

XW

48. The diagram above represents the stages of a developing follicle. What other event takes place

during the time period from W to X?

A. The endometrium breaks down.

B. The uterine lining rebuilds and thickens.

C. The anterior pituitary secretes decreasing amounts of luteinizing hormone (LH).

D. The hypothalamus shuts off the production of follicle-stimulating hormone (FSH).

49. The event shown at time X occurs as a result ofA. the release of large amounts of LH and FSH.

B. the secretion of oxytocin while breast feeding.

C. the secretion of human chorionic gonadotropin (HCG).

D. a steady decline in FSH, LH, estrogen and progesterone.


100/575

OVER- 17 -

50. The presence of human chorionic gonadotropin (HCG) in a womans urine indicates that she

A. is pregnant.

B. has just ovulated.

C. is about to menstruate.

D. has decreased estrogen levels.



101/575

- 18 -








1. State a different function for each of the following in the human body.

(3 marks: 1 mark each)

Monosaccharides:

Amino acids:

Glycogen:


102/575

OVER- 19 -

2. Describe the process of DNA replication. (3 marks)


103/575

- 20 -

Use the following chart to answer question 3.

Three-letter codons of messenger RNA and the amino acids specified by the codons

AAUAAC

AAAAAG

Asparagine

Lysine

CAUCAC

CAACAG

Histidine

Glutamine

GAUGAC

GAAGAG

Asparatic acid

Glutamic acid

UAUUAC

UAAUAG

Tyrosine

Stop

AGUAGC

AGAAGG

Serine

Arginine

UGUUGC

UGAUGG

Cysteine

StopTryptophan

AUUAUC

AUA

AUG

Isoleucine

Methionine

UUUUUC

UUAUUG

Phenylalanine

Leucine

ACUACCACAACG

Threonine

CCUCCCCCACCG

Proline

GCUGCCGCAGCG

Alanine

UCUUCCUCAUCG

Serine

CGUCGCCGACGG

Arginine

GGUGGCGGAGGG

Glycine

CUUCUCCUACUG

Leucine

GUUGUCGUAGUG

Valine

3. a) Determine the DNA base sequence that codes for the amino acid tryptophan. (1 mark)

b) Determine the anticodon for tryptophan. (1 mark)


104/575

OVER- 21 -

4. Describe how increased vascularization aids in the development of cancer. (2 marks)


105/575

- 22 -


5. Give three functions of the structure above. (3 marks)

i)

ii)

iii)


106/575

OVER- 23 -

6. The addition of heavy metals, boiling water or acid all have the same effect on the rate of

an enzyme-catalyzed reaction. Describe the effect that these additions have on the enzyme

and the reaction rate. (4 marks)


107/575

- 24 -


X

Y

W

Z

7. Identify each of the labelled structures and give one function of each.

(6 marks: 12mark each for name; 1 mark each for function)

Part W:

Name:

Function:

Part X:

Name:

Function:

Part Y:

Name:

Function:

Part Z:

Name:

Function:


108/575

OVER- 25 -

8. Describe tissue-capillary fluid exchange. (5 marks)


109/575

- 26 -

9. Describe how the characteristics of the lungs assist in the function of gas exchange. (4 marks)


110/575

OVER- 27 -

10. Describe how a nerve impulse moves across a synapse. (5 marks)


111/575

- 28 -


U

V

W

X

Y

Z

11. State a different function of each of the labelled structures. (6 marks: 1 mark each)

Part U:

Part V:

Part W:


112/575

OVER- 29 -

Part X:

Part Y:

Part Z:


113/575

- 30 -

12. a) Give one function of each of the following in a male. (3 marks: 1 mark each)

Luteinizing hormone (LH):

Follicle-stimulating hormone (FSH):

Testosterone:

b) i) Name two structures that contribute to the production of seminal fluid. (2 marks)

i)

ii)

ii) Give two functions of seminal fluid. (2 marks)

i)

ii)

END OF EXAMINATION


114/575

Question 1:

1. .

(3)

Question 2:

2. .

(3)

Question 3:

3. .

(2)

Question 4:

4. .

(2)

Question 5:

5. .

(3)

Question 6:

6. .

(4)

Question 7:

7. .

(6)

Question 8:

8. .

(5)

Question 9:

9. .

(4)

Question 10:

10. .

(5)

Question 11:

11. .

(6)

Question 12:

12. .

(7)



batch and sequence number

BIOLOGY 12

November 1999

Course Code = BI

Use this space if I.D. sticker is not available.

W R I T E S T U D E N T I . D . N U M B E R ( P E N )

I N T H I S S P A C E


115/575

991bik - 1 - February 23, 1999

Biology 12January 1999 Provincial Examination

ANSWER KEY/ SCORING GUIDE

Curriculum:

Organizers Sub-Organizers1. Cell Biology

2. Cell Processesand Application

3. Human Biology

A, B, C, D

E, F, G, H

I, J, K, L, M, N, O, P

Part A: Multiple Choice

Q K C CO PLO Q K C CO PLO

1. D K 1 A1, 3 26. B U 3 K1

2. C H 1 A1; H1 27. B H 3 K23. D U 1 A1 28. D U 3 K1, 6

4. D H 1 A1, 2; G5 29. C U 3 L1

5. C K 1 B3 30. D K 3 L1

6. C H 1 B3 31. C U 3 L1, 5

7. C U 1 C1, 2 32. D K 3 L7

8. D K 1 C2; D1 33. A U 3 L8; J2

9. B K 1 C2, 8; G1 34. D U 3 N2

10. C U 1 C3 35. C K 3 N3

11. A K 1 C9 36. A K 3 N412. D K 1 C2, 12 37. A U 3 N4

13. B H 1 D2 38. A K 3 O1

14. B K 2 G1 39. B U 3 O2

15. A H 2 G3, 4 40. C H 3 O2, 4, 5

16. C H 2 G4, 8 41. D E L E T E D

17. C H 2 G6 42. D K 3 O4

18. D U 2 H3 43. D K 3 P1

19. D U 3 I1, 2 44. C K 3 P1

20. C U 3 I1, 2 45. D K 3 P321. D U 3 I1, 9 46. B K 3 P4

22. A U 3 I2 47. C H 3 P5, 6

23. B U 3 I2 48. C H 3 P9, 10

24. B U 3 I2 49. A U 3 P10

25. C K 3 J1 50. B K 3 P7, 9, 10

Multiple Choice = 50 marks


116/575

991bik - 2 - February 23, 1999

Part B: Written Response

Q B C S CO PLO

1. 1 K 4 1 D1

2. 2 U 3 2 E1

3. 3 U 4 2 F4

4. 4 H 8 2 H6; I2, 45. 5 U 10 3 J2, 5, 6

6. 6 U 3 3 L2

7. 7 U 8 3 M3, 4

8. 8 U 6 3 O1, 2

9. 9 K 4 3 P7

Written Response = 50 marks

Multiple Choice = 50 (50 questions)

Written Response = 50 (9 questions)

EXAMINATION TOTAL = 100 marks

LEGEND:

Q = Question Number B = Score Box Number S = Score

K = Keyed Response C = Cognitive Level CO = Curriculum Organizer

PLO = Prescribed Learning Outcome


117/575

991bik - 3 - February 23, 1999








1. Describe the structure of DNA. (You may use a labelled diagram to answer this question.)

(4 marks)

It consists of two polynucleotide strands.

It is a double helix OR ladder configuration.

Its sugar is deoxyribose.

It has bases A, T, C and G. There is hydrogen bonding between the complementary

bases (AT, CG) on the two polynucleotides.

It is composed of nucleotides.

Each nucleotide is composed of sugar, phosphate and base.

It has a sugar-phosphate backbone.

any four for1 mark each


118/575

991bik - 4 - February 23, 1999

2. State one role for each of the following molecules in the process of protein synthesis.

(3 marks)

DNA:

Contains the genetic code for protein synthesis.

Serves as a template for the transcription of mRNA.

either one for1 mark

mRNA:

Carries the transcribed code to the ribosome for translation.

Determines the amino acid sequence of the polypeptide produced.

either one for1 mark

tRNA:

Carries specific amino acid to a codon on the mRNA.

Binds to a specific amino acid.

Ensures the correct amino acid sequence in the new polypeptide

through complementary base pairing of codons and anticodons.

any one for1 mark


119/575

991bik - 5 - February 23, 1999

3. Describe the process of carcinogenesis. (4 marks)

During initiation, a carcinogen brings about a mutation.

During promotion, cancerous growth is triggered.

Vascularization occurs.

A mutagen converts a proto-oncogene to an oncogene.

Metastasis occurs (cancer spreads to other sites).

There is a loss of contact inhibition between the cells. The cells develop abnormal nuclei.

The cytoskeleton of the cells is altered.

any four for1 mark each


120/575

991bik - 6 - February 23, 1999

4. In an experiment designed to test the effects of environmental conditions on the ability of

enzymes to digest food, the following steps are carried out:

Four test tubes are labelled A, B, C and D.

All tubes contain distilled water and a small amount of egg white (protein).

Individual tubes have additional contents as shown in the table below.

All tubes are to be incubated at 37C for one hour.

For each tube, explain what will happen and why.

(8 marks: 1 mark each for result; 1 mark each for explanation)

TUBEINITIAL

CONTENTSADDITIONALCONTENTS RESULT AND EXPLANATION

B

C

D

distilled water+

egg white

distilled water+

egg white

distilled water+

egg white

pepsin

pepsin+

hydrochloric acid(at pH 3)

hydrochloric acid(at pH 3)

Adistilled water

+

egg white

noneNo digestion occurs (1 mark)because no enzyme is present. (1 mark)

Little or no digestion occurs (1 mark)because pH is not optimum. (1 mark)

Digestion occursPeptides are produced

because the correct enzyme and optimumpH are present. (1 mark)

Little or no digestion occurs (1 mark)because no enzyme is present. (1 mark)

(There is limited hydrolysis by HCl at 37C.)

either onefor 1 mark


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991bik - 7 - February 23, 1999

Use the following diagram to answer question 5a).

U

V

X

Y

Z

W

5. a) For each blood vessel listed in the table below, write the letter from the diagram which

indicates the vessels location. (2 marks: 12 mark each)

BLOOD VESSELLETTER FROM

DIAGRAM

Iliac artery

Aorta

Carotid artery

Subclavian artery

U

Z

W

X


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991bik - 8 - February 23, 1999

b) In the table below, contrast the structure and/or function of the hepatic vein versus

the hepatic portal vein. (4 marks)

After a meal, carriesblood lower in glucosethan the hepatic portalvein.

After a meal, carriesblood higher in glucosethan the hepatic vein.

Between meals, carriesblood higher in glucosethan the hepatic portal

vein.

Between meals,carries blood lower inglucose than the hepatic

vein.

Joins the liver and theinferior vena cava. Joins the digestivetract and the liver.

Starts in a capillarybed and ends in avessel.

Starts and ends incapillary beds.

Carries blood higher inurea than the hepaticportal vein.

Carries blood lower inurea than the hepaticvein.

HEPATIC VEIN HEPATIC PORTAL VEIN

CONTRASTS

Larger in diameter.

Carries purified bloodaway from the liver.

Part of systemic

circulatory system.

Part of portal system.

Carries blood containingpoisons to the liver.

Smaller in diameter.

any two contrasting pairfor 2 marks per pair

Note to markers: Students must show a valid contrast. No single marks should be given if student fills inonly one of the pair of boxes.


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991bik - 9 - February 23, 1999

c) Name two structures present in fetal but not in adult circulatory systems and describe

the function of each. (4 marks: 1 mark each for name; 1 mark each for function)

Students may choose any two of the following:

Name: oval opening

Function: Allows blood to move from the right to the left atrium, bypassing the pulmonary circuit.

Name: arterial duct

Function: Allows blood to move from the pulmonary artery and the aorta, bypassing the

pulmonary circuit.

Name: umbilical arteries

Function: Take blood containing wastes to the placenta.

Name: umbilical vein

Function: Brings nutrient-rich blood from the placenta.

Name: venous duct

Function: Allows blood to flow from the umbilical vein to the inferior vena cava.

Name: umbilical cord

Function: Carries O2 /nutrients from the placenta; carries wastes to the placenta.


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991bik - 10 - February 23, 1999

6. Describe how the upper respiratory tract is specialized to keep the lungs free of debris.

(3 marks)

Mucus traps debris.

Cilia sweep debris back up to the glottis.

Cilia filter the air.

Hairs in the nasal passages filter the air.

Coughing moves debris up and out of the respiratory tract. Epiglottis blocks food from entering the lungs.

Saliva traps particles.

any three for1 mark each


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991bik - 11 - February 23, 1999

7. Describe the transmission of a nerve impulse through a neuron. (8 marks)

Through a neuron:

Depolarization of postsynaptic membrane occurs.

OR

Neurotransmitter attaches to receptors on the

postsynaptic membrane.

Membrane is polarized. Sodium ion gates open.

Sodium ions diffuse into the neuron.

Depolarization occurs.

Membrane potential is + 40mV (upswing). Sodium ion gates close.

Potassium ion gates open.

Potassium ions diffuse out of the neuron.

Repolarization occurs.

Membrane potential is 65mV (downswing). Myelinated fibres allow faster transmission because

the action potential travels from node to node.

Sodium-potassium pump re-establishes resting

potential.

Transmission occurs in one direction only.

At the synapse:

Action potential reaches the end of the axon.

Presynaptic membrane becomes permeable to calcium.

Calcium ions cause microfilaments to pull synaptic

vesicles to inner surface of presynaptic membrane.

Vesicles release neurotransmitter into the synaptic cleft.

any eight for1 mark each


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991bik - 12 - February 23, 1999

8. Give two functions of each of the following urinary system structures. (6 marks)

Kidney:

Helps maintain pH. Excretes nitrogenous wastes, excess salts and H2O

or produces and excretes urine.

Helps maintain water balance. Removes histamines, penicillin, etc.

Helps maintain nutrient and mineral balance.

Purifies blood.

Regulates blood volume.

any two for1 mark each

Collecting duct:

Reabsorbs water.

Carries urine to the renal pelvis.

Regulation of pH.

Regulates blood volume.


Proximal tubule:

Selective reabsorption of salts.

Selective reabsorption of amino acids.

Selective reabsorption of glucose.

Reabsorption of water.

Active transmission of nutrients.

Moves filtrate to the loop of Henle.



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991bik - 13 - February 23, 1999

9. Label the following diagram in the blanks provided. (4 marks)

uterusor

uterine wall

oviductor

fallopian tube

ovary

vagina

END OF KEY


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MINISTRY USE ONLY

Place Personal Education Number (PEN) here.


MINISTRY USE ONLY

Place Personal Education Number (PEN) here.

MINISTRY USE ONLY

Biology 12

AUGUST 2001

Course Code = BI

Student Instructions

1. Place the stickers with your PersonalEducation Number (PEN) in the allottedspaces above. Under no circumstance isyour name or identification, other thanyour Personal Education Number, to

appear on this booklet.

2. Ensure that in addition to this examinationbooklet, you have an ExaminationResponse Form. Follow the directions onthe front of the Response Form.

3. Disqualification from the examination willresult if you bring books, paper, notes orunauthorized electronic devices into theexamination room.

4. When instructed to open this booklet, checkthe numbering of the pages to ensure thatthey are numbered in sequence from pageone to the last page, which is identified by

END OF EXAMINATION .

5. At the end of the examination, place yourResponse Form inside the front cover of thisbooklet and return the booklet and yourResponse Form to the supervisor.


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Question 1:

1. .

(8)

Question 2:

2. .

(4)

Question 3:

3. .

(3)

Question 4:

4. .

(4)

Question 5:

5. .

(5)

Question 6:

6. .

(7)

Question 7:

7. .

(7)

Question 8:

8. .

(7)

Question 9:

9. .

(5)


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BIOLOGY 12

AUGUST 2001COURSE CODE = BI


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1. Electronic devices, including dictionaries and pagers, are not permitted in theexamination room.

2. All multiple-choice answers must be entered on the Response Form using anHB pencil. Multiple-choice answers entered in this examination booklet will notbe marked.

3. For each of the written-response questions, write your answer in ink unlessotherwise instructed in the space provided in this booklet.

4. Ensure that you use language and content appropriate to the purpose and audienceof this examination. Failure to comply may result in your paper being awarded azero.

5. This examination is designed to be completed in twohours. Students may,however, take up to 30 minutes of additional time to finish.


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ValueSuggested

Time1. This examination consists oftwo parts:





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OVER- 1 -





X

Y

Z

W

1. Which of the organelles in the diagram packages proteins for secretion?

A. W

B. X

C. Y

D. Z

________________________________________________

2. Chromosomes are composed of

A. tRNA and DNA.

B. tRNA and lipids.

C. DNA and proteins.

D. RNA and ribosomes.


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- 2 -

3. In contrast to the nuclear envelope, the inner membrane of the mitochondrion

A. contains pores.

B. has many folds.

C. is not permeable.

D. has two phospholipid layers.

4. Which organelle provides the energy for protein synthesis?

A. nucleus

B. nucleolus

C. mitochondrion

D. rough endoplasmic reticulum

5. Neutral fats do not dissolve in water because

A. water is non-polar.

B. water is polar and neutral fats are non-polar.

C. neutral fats are polar and form hydrogen bonds with water.

D. neutral fats break down into ions when combined with water.

6. Which of the following describes the action of a buffer?

A. Lysosomes hydrolyze proteins in the cell.B. During exercise, hemoglobin accepts hydrogen ions (H+ ).

C. Gastric secretions denature salivary amylase in the stomach.

D. Reduced hemoglobin reacts with oxygen to form oxyhemoglobin in the lungs.


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OVER- 3 -

7. Which of the following diagrams represents glucose?

A.

B.O

C.O O

D.OOO

8. Unsaturated fatty acids, like those found in fish oils, are characterized by

A. the ability to bond with glycerol to make lipids.

B. bonds between an amine and a carboxyl (acid) group.

C. having only single bonds between the carbon atoms in the chain.

D. some carbon atoms in the chain that bond to only one hydrogen atom.

9. If 20% of the base molecules are guanine, how many thymine molecules are present in a DNA

molecule with 1 000 bases?

A. 200B. 300

C. 400

D. 600


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- 4 -


x y

GCC

G

AT

x y1 yx1

+

x y x y1 x1 y

10. The diagram above represents

A. DNA replication.

B. mRNA translation.

C. mRNA elongation.D. DNA transcription.

11. The process shown in the diagram occurs in the

A. nucleus.

B. nucleolus.

C. ribosomes.

D. rough endoplasmic reticulum.


uracil

adenine

thymine

phosphate

deoxyribose

12. RNA contains how many of the molecules above?

A. one

B. two

C. three

D. four


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OVER- 5 -

13. Worn-out red blood cells are removed from the blood by the process of

A. osmosis.

B. exocytosis.

C. endocytosis.

D. simple diffusion.

14. The hormone responsible for increasing the rate at which cells release energy from

carbohydrates is

A. ATP.

B. ADH.

C. thyroxin.

D. aldosterone.


X


A. product.

B. enzyme.

C. substrate.

D. enzyme-substrate complex.

________________________________________________

16. Bicarbonate ions and digestive enzymes are present in secretions from the

A. liver.B. stomach.

C. pancreas.

D. small intestine.


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- 6 -


X

Y

Z

V

W

17. Which letter identifies the gall bladder?

A. V

B. X

C. Y

D. Z

18. Which organ is involved in maintaining a constant level of glucose in the blood?

A. V

B. W

C. X

D. Z

________________________________________________

19. Which of the following substances is chemically digested by a component of saliva?

A. lipidB. starch

C. protein

D. nucleic acid


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OVER- 7 -

20. Lipase, when added to gastric juice, is ineffective due to the presence of

A. mucus.

B. trypsin.

C. bicarbonate ions.

D. hydrochloric acid.

21. Villi are found in the

A. esophagus.

B. liver.

C. small intestine.

D. stomach.

22. Which of the following blood vessels have thin, permeabl

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