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Ministry of Education Departmental Examinations Released Questions
BIOLOGY
September 2016
Table of Contents
A. Released Questions (2016) – Biology 8255.....................................................................................................4
1. BI30-LE1 Explore how scientific understandings of life and its characteristics change in light of new evidence......................................................................................................................................................4
2. BI30-LE2 Examine the significance of evolution as a key unifying theme in biology through the principles, processes and patterns of biological evolution..........................................................................5
3. BI30-OL1 Investigate cell structure and processes, including energy transfer, and transport of materials, in unicellular and multicellular organisms which are representative of each kingdom............12
4. BI30-OL2 Compare the anatomy, physiology and behaviours of multicellular organisms including protists, fungi, plants and animals.............................................................................................................14
5. BI30-OL3 Explore how the dynamic nature of biological classification reflects advances in scientific understanding of relationships among organisms.....................................................................................15
6. BI30-GB1 Explore classical (i.e. Mendelian) and current (i.e. chromosomal) understandings of biological inheritance................................................................................................................................17
7. BI30-GB2 Investigate how genetic information is stored, transmitted and expressed at the molecular level...........................................................................................................................................................23
8. BI30-GB3 Explore the impacts of historical, current and emerging biotechnologies on self, society and the environment.................................................................................................................................26
B. Released Questions (2016) – Chemistry 8256 Solution Pages......................................................................28
1. BI30-LE1 Explore how scientific understandings of life and its characteristics change in light of new evidence....................................................................................................................................................28
2. BI30-LE2 Examine the significance of evolution as a key unifying theme in biology through the principles, processes and patterns of biological evolution........................................................................29
3. BI30-OL1 Investigate cell structure and processes, including energy transfer, and transport of materials, in unicellular and multicellular organisms which are representative of each kingdom............31
4. BI30-OL2 Compare the anatomy, physiology and behaviours of multicellular organisms including protists, fungi, plants and animals.............................................................................................................32
5. BI30-OL3 Explore how the dynamic nature of biological classification reflects advances in scientific understanding of relationships among organisms.....................................................................................32
6. BI30-GB1 Explore classical (i.e. Mendelian) and current (i.e. chromosomal) understandings of biological inheritance................................................................................................................................33
7. BI30-GB2 Investigate how genetic information is stored, transmitted and expressed at the molecular level...........................................................................................................................................................35
8. BI30-GB3 Explore the impacts of historical, current and emerging biotechnologies on self, society and the environment.................................................................................................................................36
This information package is intended for teachers preparing students for the Biology 30 departmental examination.
A.Released Questions (2016) – Biology 8255
1. BI30-LE1 Explore how scientific understandings of life and its characteristics change in light of new evidence.
1. All living things are adapted to obtain resources, such as food, from the environment. Which characteristic of life is this an example of?
A. use of energyB. reproductive ability C. responding to stimuli D. growth and development
2. What does the endosymbiotic theory state about the origins of mitochondria and chloroplast?
A. They were once free-living bacteria.B. They evolved into free-living bacteria.C. They increased in size and became eukaryotic cells.D. They developed from eukaryotic cells that decreased in size.
3. Pasteur’s experiment to disprove abiogenesis involves two sets of flasks containing nutrient-rich broth - one set of flasks with a goose-neck and one set with a normal, straight-neck. Assuming abiogenesis is false, which set of flasks should spoil?
A. both sets of flasksB. goose-necked flasksC. neither set of flasksD. straight-neck flasks
4. Why are scientists not able to agree on whether or not viruses are alive?
A. Viruses cannot evolve but can infect living cells.B. Viruses cannot reproduce inside living cells but can evolve.C. Viruses cannot infect living cells but can live independently.D. Viruses cannot live independently but can reproduce inside
living cells.
2. BI30-LE2 Examine the significance of evolution as a key unifying theme in biology through the principles, processes and patterns of biological evolution.
1. Chimpanzees, gorillas, and humans share similar anatomy and physiology. These similarities provide evidence for which concept of evolution?
A. coevolution B. common ancestryC. divergent evolutionD. convergent evolution
2. Lamarck proposed several ideas in his theory of evolution. Which of the following is one idea unique to Lamarck?
A. the theory of use and disuseB. that individuals compete for resourcesC. that more offspring can be produced than can surviveD. that traits occur due to changes at the genetic level and,
therefore, are passed onto the next generation
3. In a species of butterfly, black (B) colour is dominant to white (b). In a dark forest where birds use the butterfly as a food source, what is likely to happen to the frequency of the black gene?
A. increaseB. decreaseC. fluctuateD. remain constant
4. It had long been believed that drinking milk in adulthood was the human norm. However, in human diet studies, it has been found that most adults are lactose intolerant after childhood and they avoid drinking milk.
Lactose intolerance is caused by the lack of the enzyme lactase that breaks down lactose (milk sugar) into glucose and galactose.
In most humans, the intestinal lactase enzyme decreases rapidly with age. By the time children reach three or four years old, they cannot digest lactose.
Studies have shown that populations of humans (many Africans and northern Europeans) that have kept dairy cattle for thousands of years have kept the milk-drinking habit and the ability to digest lactose throughout their lives.
Northern Europeans are almost 100% lactose tolerant. They benefit from the vitamin D content of milk because they live at high latitudes that may prevent them from making enough vitamin D on their own. This suggests that the availability of dairy cattle has
A. produced an entire generation of lactose intolerant adults.B. created selection pressure on dairy cattle to produce milk
without lactose.C. produced lactose tolerance in those adults that eat fermented
milk products like yogurt.D. created selection pressure on the human gene pool that
favours those with the gene for lactase.
5. Which one of the following statements would disprove part of Lamarck’s theory of evolution?
A. Fossils of animals closely resemble modern animals.B. Giraffes with stretched necks produced offspring with longer
necks.C. Athletes passed on acquired physical development to their
children.D. The tails of successive generations of mice were cut off, but
there still was no change in the length of tails in later generations.
6. The following diagram illustrates the distribution range of fossils of a specific dinosaur.
Which of the following is a possible explanation for this distribution?
A. coevolution B. continental driftC. adaptive radiation D. convergent evolution
7. After an organism dies, the amount of radioactive carbon-14 contained within the corpse falls over time as illustrated by the following graph.
A bone discovered during an archeological dig in China is analyzed and found to be 12 000 to 13 000 years old. With the aid of the graph, what is the probable carbon-14 content of the bones?
A. 5% to 10% carbon-14B. 15% to 20% carbon-14C. 50% to 60% carbon-14D. 75% to 80% carbon-14
8. Consider the following cladogram.
Which of the following does NOT represent a clade?
A. 1, 2, 3, 4B. 5, 6C. 7, 8, 9D. 5, 6, 7, 8, 9
Use the following information to answer questions 9 and 10.
The graph shows the relationship between mammalian brain size and mammalian body mass. Primates (monkeys and apes) are shown as filled circles and other mammalian species are unfilled circles.
9. How does the brain size of mammals change as body mass increases?
A. Brain size increases.B. Brain size decreases.C. Brain size remains the same.D. Body mass does not relate to brain size.
10. Which of the following statements is true about humans’ position on the graph?
A. Humans have the lowest body mass of all primates.B. Humans have the largest brain size of all primates.C. Humans have the largest body mass of all primates.D. Humans have the smallest brain size of all primates.
______________________________
11. Who is normally given credit for the theory of natural selection?
A. Lamarck and LyellB. Darwin and WallaceC. Malthus and DarwinD. Malthus and Wallace
12. Lamarck’s theory of evolution was based on the ability of organisms to pass on acquired characteristics to their offspring. Darwin questioned Lamarck’s hypothesis, but like Lamarck, what idea could Darwin not satisfactorily explain?
A. how natural selection occursB. how the environment changesC. how characteristics were inheritedD. how competition for survival occurs
3. BI30-OL1 Investigate cell structure and processes, including energy transfer, and transport of materials, in unicellular and multicellular organisms which are representative of each kingdom.
1. Which of the following is the correct order from lowest to highest magnification?
A. hand lens, human eye, light microscope, electron microscopeB. human eye, hand lens, light microscope, electron microscopeC. hand lens, human eye, electron microscope, light microscopeD. human eye, hand lens, electron microscope, light microscope
2. The extremophile archean organism Thermus aquaticus exhibits adaptations such as a stable cellular membrane and heat resistant enzymes. In what type of environment would it be adapted to survive?
A. low salt contentB. low temperatureC. high salt contentD. high temperature
3. During an experiment, a cell is placed into a solution containing a dye. After a few hours, the concentration of the dye inside the cell is higher than in the external solution. The same experiment is performed again in the presence of a substance that inhibits the use of ATP. In this case, the dye did not enter the cell. What is the most probable mechanism by which the dye entered the cell in the first experiment?
A. osmosis B. diffusionC. exocytosisD. active transport
4. What is light energy used for during photosynthesis?
A. to produce ATPB. to produce carbon dioxide C. to produce water moleculesD. to break down sugar molecules
5. Consider the following images.
What is the amoeba attempting to complete during steps 4 and 5?
A. The amoeba is undergoing mitosis.B. The amoeba is undergoing exocytosis.C. The amoeba is returning to its original size and shape.D. The amoeba is using a pseudopod to change its direction of
movement.
6. Cellular respiration is the process by which organisms release energy from organic compounds. Which products of this reaction are needed in photosynthesis?
A. carbon dioxide and waterB. glucose and oxygenC. glucose and waterD. carbon dioxide and oxygen
4. BI30-OL2 Compare the anatomy, physiology and behaviours of multicellular organisms including protists, fungi, plants and animals.
1. Stomach acid has a pH of 2 while the rest of the body has a pH of 7.4. The pancreas in humans produces the bicarbonate ion
which is used to neutralize acid coming from the stomach to the small intestine.
The ability of the pancreas to neutralize acidity is an example of which biological process?
A. digestionB. homeostasisC. osmoregulationD. cellular respiration
2. A mushroom is the reproductive structure of some fungi which grows upward out of the ground. What type of response is used in this process?
A. positive gravitropismB. negative gravitropism C. positive chemotropismD. negative phototropism
3. Grass has been used to study the ability of plants to bend toward light. Studies show that grass produces a chemical at the top of each blade which is transported down to the base of the plant.
What is the ability to grow towards light called?
A. gravitropismB. phototropism C. hydrotropismD. chemotropism
5. BI30-OL3 Explore how the dynamic nature of biological classification reflects advances in scientific understanding of relationships among organisms.
1. Which of the following explanations is a reason why biological classification systems have changed over time?
A. Different organisms share major characteristics that make them difficult to group.
B. As scientists popularity changes, support for their proposed classifications changes.
C. Species have adapted and evolved and no longer fit within the current classification.
D. Life discovered on other planets does not fit into the current classification system.
2. There are finches, such as Geospiza fuliginosa, Geospiza fortis, and Geospiza magnirostis, in the Galapagos islands. Which of the following statements is true, based on the above information?
A. All finches belong to the same genus.B. All finches belong to the same species.C. All finches are found on the same island.D. All finches have the same physical characteristics.
3. Refer to the diagram below.
Which of the following does the above illustration represent?
A. cladogramB. taxonomic rankC. dichotomous keyD. binomial nomenclature
4. Which of the following statements is true of protists, Eubacteria, and Archaebacteria?
A. Archaebacteria possess nuclei while protists lack specific nuclei.
B. Protists possess nuclei while Eubacteria and Archaebacteria lack nuclei.
C. Protists possess pseudo nuclei while Eubacteria and Archaebacteria possess true nuclei.
D. Protists possess multiple nuclei while Eubacteria and Archaebacteria possess single nuclei.
6. BI30-GB1 Explore classical (i.e. Mendelian) and current (i.e. chromosomal) understandings of biological inheritance.
1. In garden peas, yellow seeds are dominant over green seeds. When pure bred pea plants that produce yellow seeds are crossed with a pea plant that produces green seeds, what alleles will the plants inherit?
A. two alleles for green seed colourB. two alleles for yellow seed colourC. alleles from only the pea plant producing yellow seedsD. an allele for yellow seed colour and an allele for green seed
colour
2. A person with the genotype has blood type AB. What mechanism of genetic inheritance does this illustrate?
A. codominanceB. complete dominanceC. incomplete dominanceD. multiple allelic inheritance
3. In guinea pigs, black (B) hair is dominant to white (b) hair colour. What are the genotypes of homozygous and heterozygous black guinea pigs?
A. BB and BBB. BB and BbC. both blackD. black and grey
4. Two colour morphs of a grasshopper are controlled by a single gene with two alleles. The G allele produces green grasshoppers and is dominant over the g allele which produces yellow grasshoppers. The life cycle of this grasshopper is one year and each year the population is replaced by its descendants. Data for one large population over a period of 60 years is shown in the graph below.
Which of the following is responsible for the change in allele frequencies from 1975 to 1980?
A. mutationB. gene flowC. selection against green coloured grasshoppersD. selection against yellow coloured grasshoppers
5. What conclusion was made based on the results of Gregor Mendel’s research?
A. Physical traits in pea plants are determined by DNA.B. Physical traits in bacteria are determined by chromosomes.C. Physical traits in bacteria are passed down through
generations.D. Physical traits in pea plants are passed down through
generations.
6. Two parents are both lactose intolerant and tend to have children who are also lactose intolerant. However, if at least one parent can digest lactose normally, their children can usually digest lactose as well. What type of inheritance is most likely responsible for the lactose gene?
A. recessiveB. sex-linkedC. dominanceD. incomplete dominance
7. The diagram indicates the results for a cross in Alaskan malamutes (dogs). The trait for normal sized dogs (D) is dominant to the dwarf (d) allele.
d d
D 1 3
d 2 4
What would be the genotypic results produced from the mating of individuals 1 and 3 from the F1 generation?
A. all ddB. all DdC. 1 Dd : 1 ddD. 1 DD : 2 Dd : 1 dd
8. The following diagram represents a human pedigree of ACHOO syndrome.
ACHOO syndrome, commonly known as sun sneezing, is a condition of humans characterized by the uncontrollable sneezing in response to the exposure to bright light.
What are the genotypes of parents 2 and 3 in generation II?
A. Aa and aaB. Aa and AAC. aa and AAD. Aa and Aa
9. In organisms, genetic variation is introduced during which event?
A. anaphase of meiosisB. Prophase I of meiosisC. cytokinesis of meiosisD. crossing over in mitosis
10. A biologist discovered a population of small mouse-like creatures on an isolated island in the middle of the Pacific. The island is made up primarily of dense dark overgrowth on black volcanic soil. The creatures are either brown or white. Brown coat colour is recessive.
When the biologist returns in twenty years, she finds that a small number of these creatures are black. The black gene is discovered to be recessive to brown and white.
What was responsible for the introduction of the black phenotype?
A. mutationB. migrationC. random matingD. chromosomal recombination
11. Consider the following karyotype.
What chromosomal abnormality is responsible for this individual’s karyotype?
A. deletionB. inversionC. translocationD. non-disjunction
7. BI30-GB2 Investigate how genetic information is stored, transmitted and expressed at the molecular level.
1. Sickle cell anemia, a disorder where red blood cells are crescent shaped rather than disk shaped, results when the amino acid glutamate that is normally present in the sixth position on the protein is replaced with valine.
Sickle cell hemoglobinVal – His – Leu – Thr – Pro – Val
What is the DNA sequence for sickle cell anemia?
A. GTG – CAC – CTG – ACT – CCT – UCGB. GTG – CAC – CTG – ACT – CCT – CCCC. GTG – CAC – CTG – ACT – CCT – ACTD. GTG – CAC – CTG – ACT – CCT – GTG
2. Which of the following statements regarding epigenetic inheritance is true?
A. It involves the alteration of mRNA code.B. It involves no change in an organism’s DNA sequence.C. It can temporarily affect an individual then return to normal.D. It occurs when a group of genes is expressed during
embryonic development.
3. You are a detective investigating a crime scene. The perpetrator of the crime was not particularly careful and left a droplet of blood at the scene.
Samples from four suspects were collected, and a DNA fingerprint was created for each sample as indicated below.
Who should be arrested?
A. JakeB. AvaC. GaryD. Kate
4. What structure joins two sister chromatids?
A. a gene B. a telomere C. a chromosomeD. a centromere
5. Who first described the structure of DNA?
A. MendelB. ChargaffC. Watson and CrickD. Wilkins and Franklin
6. Tay Sachs disease is a rare genetic disorder that causes damage to the nervous system. Examine the DNA sequences below that show a normal gene and a mutated gene that produces Tay Sachs disease.
Normal gene: CGT ATA TCC TAT GCC CCT GACTay Sach’s gene: CGT ATA TCT ATG CTA TGC CCT GAC
What would happen when the Tay Sach’s gene is translated into a protein?
A. No protein would be produced.B. The same amino acid sequence would be formed.C. The amino acid sequence would be different after the third
amino acid.D. The amino acid sequence would be different after the second
amino acid.
7. What is the role of tRNA in protein synthesis?
A. transports amino acids to the nucleusB. carries the DNA code from the nucleusC. transports amino acids to the ribosomesD. carries the DNA code from the ribosomes
8. What is the name of the laboratory technique used to make multiple copies of a segment of DNA?
A. polymerase chain reactionB. gel electrophoresisC. DNA sequencingD. gene therapy
8. BI30-GB3 Explore the impacts of historical, current and emerging biotechnologies on self, society and the environment.
1. Direct manipulation of an organism’s genome by deleting or adding genetic information started in the early 1970’s. One of the first human uses was the development of insulin-producing bacteria.
This example highlights which of the following technologies?
A. synthetic biology B. selective breedingC. genetic engineeringD. survival of the fittest
2. The Belgian blue breed of cattle has a mutation in the myostatin gene that causes both cows and bulls to overproduce lean muscle tissue. Modern Belgian blues have an average of 20% more muscle than cattle of other breeds. How have farmers ensured the maintenance of this breed?
A. By allowing Belgian blues to mate with only other breeds of cattle.
B. By allowing Belgian blues to mate with only other Belgian blues.
C. By genetically engineering cattle embryos to contain the mutated myostatin gene.
D. By mating cattle with the myostatin gene mutation with non-mutated cattle to spread the mutation.
3. Since the Flavr Savr tomato was approved by the Food and Drug Administration in the US in 1994, varieties of genetically modified corn, soya, sugar beets, and canola have become common Canadian crops. These varieties contain modifications to their genes to make them easier to transport, larger in size/yield, and chemically resistant, among other enhancements. In only 20 years, genetically modified ingredients have made their way into most of Canada’s processed foods.
What is a negative effect of introducing genetically modified agricultural seeds into Canadian farms?
A. increased crop yield leading to increased demand on the farmer
B. decreased availability of chemical treatments leading to decreased crop yield
C. increased resistance to chemical treatments leading to increased costs to the farmer
D. decreased initial costs to the farmer as genetically modified seeds are less expensive than traditional seeds
B.Released Questions (2016) – Chemistry 8256 Solution Pages
1. BI30-LE1 Explore how scientific understandings of life and its characteristics change in light of new evidence.
1. A.
Organisms use food as an energy source.
2. A.
Several key organelles of eukaryotes originated as a symbiosis between separate single-celled organisms. Mitochondria and chloroplast both originated as free-living bacteria.
3. D.
Abiogenesis is the theory that life can arise from non-living matter. If the theory is assumed false, only the straight-neck flask will allow bacteria to enter to spoil the broth.
4. D.
Viruses do not have the ability to live independently but can reproduce with the help of a host cell. Reproduction is a life process.
2. BI30-LE2 Examine the significance of evolution as a key unifying theme in biology through the principles, processes and patterns of biological evolution.
1. B.
Similar anatomy and physiology provides evidence of a common ancestor.
2. A.
Only Lamarck included the idea that animals acquired characteristics after constantly using certain physical traits.
3. A.
The dark butterflies will use their color as camouflage in the dark forest to survive causing the black gene to increase in frequency.
4. D.
Dairy cattle were being used to have access to milk for hundreds of generations causing a selection pressure that favored those with the gene for lactase.
5. D.
Physically changing an organism’s appearance does not create offspring with the same characteristics.
6. B.
The two dark regions were originally connected land masses before continental drift separated them.
7. B.
From the graph, find 12 000- 13 000 on the x-axis (horizontal) scale and find where it intersects the line on the graph. Follow this point to the y-axis (vertical) scale to find the percentage of carbon-14 it contains. 15-20%
8. A.
Clade: a group of organisms believed to have evolved from a common ancestor. One branch of the diagram would represent a clade. 1, 2, and 3 are within one branch but 4 is contained within a lower branch so is not a part of the clade.
9. A.
Increasing linear relationship – as body mass increases, so does brain size.
10. B.
Primates are the solid black dots. Humans have the highest value on the graph indicating they have the largest brain size of all primates.
11. B.
Darwin and Wallace both came up with the idea of natural selection in the mid 1800s.
12. C.
In the 1800s, the idea of genes was not known so scientists could not explain how a characteristic was passed on from a parent to an offspring.
3. BI30-OL1 Investigate cell structure and processes, including energy transfer, and transport of materials, in unicellular and multicellular organisms which are representative of each kingdom.
1. B.
Lowest magnification – able to see only partial detailsHighest magnification – able to see very small detailshuman eye, hand lens, light microscope, electron microscope
2. D.
Heat resistance allows it to survive in a high temperature environment.
3. D.
The dye entered the cell with the help of ATP – a molecule used to supply energy. The use of energy by a molecule to cross a membrane is active transport.
4. A.
Light energy is used to create ATP from ADP.
5. D.
The extension of the cytoplasm is a pseudopod and is being used at an angle to change the amoeba’s direction of movement.
6. A.
Carbon dioxide and water are created during respiration and are also reactants in photosynthesis.
4. BI30-OL2 Compare the anatomy, physiology and behaviours of multicellular organisms including protists, fungi, plants and animals.
1. B.
The pancreas is helping to maintain a stable internal environment by regulating the pH level in the digestive tract. This is an example of homeostasis.
2. B.
Gravitropism is the growth or movement of plants in response to gravity. In this case, the fungi is growing away from gravity making it a negative gravitropism.
3. B.
A plant growing in response to light is called phototropism.
4. B.
Low blood sugar response causes glucagon to be secreted by the pancreas to raise the concentration of glucose in the blood stream.
5. BI30-OL3 Explore how the dynamic nature of biological classification reflects advances in scientific understanding of relationships among organisms.
1. A.
Several different organisms can share several characteristics which makes them difficult to group into a classification.
2. A.
Scientific names like those listed are created using genus species. All three have the same genus name Geopsiza.
3. A.
The diagram represents a cladogram: a diagram used in cladistics which shows relations among organisms.
4. B.
Protists have a nucleus while Eubacteria and Archaebacteria do not.
6. BI30-GB1 Explore classical (i.e. Mendelian) and current (i.e. chromosomal) understandings of biological inheritance.
1. D.
The cross is between YY and yy plants which results in all offspring being Yy. One yellow and one green color allele from each plant.
2. A.
This is an example of codominance when two types are both showing their characteristics.
3. B.
Homozygous – same allele, BB
Heterozygous – different alleles, Bb
4. C.
The green colored grasshoppers (G allele) were dying off showing a selection against green grasshoppers.
5. D.
Mendel’s experiments used pea plants and compared one generation to the next.
6. C.
When one parent is carrying a trait and can pass it along to their offspring, the trait must be dominant.
7. D.
D d
D DD Dd
d Dd dd
1 DD : 2 Dd : 1 dd
8. A
Mother in generation I is a carrier and the father is unaffected, not all of their children have the syndrome. This causes the father in generation II to be a carrier as well - Aa and the mother is unaffected – aa.
9. B.
Prophase I of meiosis is when crossing-over takes place.
10. A.
No organisms are introduced into the population as it is an isolated island. The black gene is only possible by a mutation.
11. D.
This is an example of non-disjunction - a chromosome is missing which is caused by sister chromatids not separating during cell division.
7. BI30-GB2 Investigate how genetic information is stored, transmitted and expressed at the molecular level.
1. D.
At position six, only GTG, which is transcribed into the codon GUG, will code for valine.
2. B.
Epigenetic inheritance: a parent's experiences, in the form of epigenetic tags, can be passed down to future generations. There is no change in DNA sequence.
3. B.
The suspect with an identical DNA fingerprint is Ava.
4. D.
The centromere joins sister chromatids.
5. C.
Watson and Crick discovered the double helix structure of DNA.
6. C.
The third amino acid is still the same but the fourth amino acid is different.
7. C.
tRNA transport amino acids to the ribosomes.
8. A.
Multiple copies of DNA are done using a polymerase chain reaction.
8. BI30-GB3 Explore the impacts of historical, current and emerging biotechnologies on self, society and the environment.
1. C.
This is an example of genetic engineering - the deliberate modification of the characteristics of an organism by manipulating its genetic material
2. B.
To maintain a breed, farmers would only allow Belgian Blues to mate with other cattle that also have the mutant gene.
3. C.
Resistance to chemical treatments would increase the cost to farmers.
