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QUESTION 1 In prokaryotes deoxyribonucleic acid (DNA) is found as unbound circular DNA in the (A) mitochondria. (B) chloroplasts. (C) nucleus. (D) cytosol.
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Difficulty: C
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Paper 1
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2020
QUESTION 2 Which form of inheritance usually determines traits that display continuous phenotypic variation? (A) polygenic (B) sex-linked (C) multiple allele (D) incomplete dominance
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Difficulty: C
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2020
QUESTION 3 A genome is defined as (A) the molecular unit of heredity. (B) all the genetic material in the chromosomes of an organism. (C) the sequence of triplets of DNA nucleotides that make up a gene. (D) the combination of alleles for a particular trait carried by an individual.
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Difficulty: C
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2020
QUESTION 4 The following information includes: » akey that is used to classify the types of alpine and subalpine grassland habitats « atable of abiotic and biotic data obtained from a habitat survey. Alpine and subalpine grasslands Habitat classification Moss-and-lichen- Yes — dominated mountain summit Alpine and subalpine Yes —> nutrient-enriched grassland Calcareous alpine and Basic — subalpine grassland Acidie — Adcidicalpine and subalpine grassland Abiotic physical parameter Reading Reference range for nutrient-poor soil (mg/kg) Nitrates/nitrites (mg/kg) Ammonia (mg/kg) Total phosphorous Biotic description: Small amount of low-lying moss growing on soil substrate. Predominantly low-lying grasses. Using the data in the table and the key this alpine and subalpine grassland would be classified as (A) amoss-and-lichen-dominated mountain summit. (B) an alpine and subalpine nutrient-enriched grassland. (C) acalcareous alpine and subalpine grassland. (D) an acidic alpine and subalpine grassland.
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Difficulty: C
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2020
QUESTION 5 The figure shows the diversity of marine animals since the late Precambrian time. The data is from marine animal families that have been reliably preserved in the fossil record. 19OOT families 900 living 800 today 700 600 500 400 300 200 100 Number of marine families o Triassic - Jurassic Cretaceous Paleogene Neogene Ordovician Silurian Devonian Carboniferous Precambrian Cambrian p— S ) S 600 200 W S O N S S Millions of years ago Which of the following time periods saw the greatest evolutionary radiation of the marine families? (A) Ordovician (B) Cretaceous (C) Devonian (D) Permian
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Difficulty: C
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2020
QUESTION 6 The carrying capacity of an ecosystem refers to the (A) total biomass of primary producers in the ecosystem at a given time that supports the higher trophic levels. (B) size of a population that can be supported indefinitely on the available resources and services of that ecosystem. (C) number of individual top predators in the ecosystem at a given time that can be supported by the lower trophic levels. (D) maximum population of individuals of different species that the ecosystem can support for an extended period of time.
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Difficulty: C
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2020
QUESTION 7 When predicting successional change which of the following would typically indicate that an ecosystem is progressing toward its climax community? Abundance of K-selected species | Biomass
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Difficulty: B
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2020
QUESTION 8 The table shows the daily energy input and output for a typical leaf. Incident sunlight Evaporation Heat loss (radiation) Reflection of sunligh Transmission of sunlight Calculate the daily net energy stored by the leaf. (A) 0.8kJ (B) 5.0kJ (C) 36.2kJ (D) 73.5kJ
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Difficulty: C
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2020
QUESTION 9 The table provides population statistics for a species of tree kangaroo in northern Queensland. Determine the population growth rate for tree kangaroos in 2017. (A) 14.6% (B) 15.0% C) 26.5% (D) 86.9%
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Difficulty: B
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2020
QUESTION 10 DNA profiling using polymerase chain reaction (PCR) and gel electrophoresis allows the comparison of (A) genes. (B) entire genomes. (C) DNA fragments. (D) specific sites of mutations.
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Difficulty: C
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2020
QUESTION 11 The Linnaean system originally used which type of evidence for classifying organisms? (A) physical features (B) common ancestry (C) molecular phylogeny (D) reproduction methods
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Difficulty: C
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2020
QUESTION 12 In the structure of DNA adenine pairs with which other base? (A) wuracil (B) guanine (C) cytosine (D) thymine
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Difficulty: C
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2020
QUESTION 13 Which of the following molecules is involved in the transcription of DNA? (A) RNA polymerase (B) DNA helicase (C) transfer RNA (D) amino acids
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Difficulty: C
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2020
QUESTION 14 One of the common assumptions in cladistics is that (A) (B) ©) (D) not all organisms are related by descent. the characteristics of organisms in a population stay the same over time. new kinds of organisms may arise when existing populations divide into two groups. the more shared characteristics two organisms have the more closely related they are.
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Difficulty: C
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2020
QUESTION 15 In watermelon skin colour is controlled by a single autosomal gene. The two phenotypic variants are green and striped. Two plants one homozygous for the green alleles and one homozygous for the striped alleles were crossed. The figure shows the phenotypic frequency for the initial (F ) generation and the subsequent (F ) generation. Frequency 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Key I:’ green striped Fy F| Generation A cross was then performed between members of the F| generation. What would be the expected frequency of striped watermelon in the next (F ) generation? A) 1.0 (B) 075 (C) 0.50 (D) 0.25
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Difficulty: B
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2020
QUESTION 16 The figures show the original distribution zone of Species I and some possible distribution zones of Species I after the introduction of Species I1. Species II has a competitive advantage over Species I; however it does not tolerate areas of lower rainfall. Before After possible distribution zones ~ D removed from the ecosystem original distribution zone / Rainfall Rainfall Temperature Temperature Which of the following would be an accurate prediction of the new distribution zone for Species 1? (A) Zone A i.e. no change to the distribution (B) Zone B i.e. reduced distribution within the original zone (C) Zone C i.e. new distribution outside the original zone (D) Zone D i.e. complete removal of the species from the ecosystem
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Difficulty: B
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2020
QUESTION 17 The table identifies the condition associated with a variety of ploidy changes. Chromosome number ploidy Monosomy 5 Cri du chat syndrome Trisomy 23 Klinefelter syndrome For a person with XXY sex chromosomes which condition would they have? (A) Cri du chat syndrome (B) Down syndrome (C) Klinefelter syndrome (D) Turner syndrome
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Difficulty: C
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2020
QUESTION 18 The diagram shows the abundance (n) of phenotypic and genotypic variation for the colour trait of a species of butterfly. AA Aa aa n =400 n =500 n= 1000 If these butterflies were placed in an environment with light-coloured trees which option from the table would be the most likely effect on the allelic frequencies? Frequency of allele/genotype A | 2 | AA | I = -- -- --
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Difficulty: C
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2020
QUESTION 19 The table of data shows a comparison of amino acids sequences in the same section of haemoglobin molecules from a number of different species. From the given information which of the following species’s haemoglobin protein is most similar to human haemoglobin protein? Species ’ Sequence of amino acids | Ly | Go | b | B | | Go o oL [ o [ o o
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Difficulty: C
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2020
QUESTION 20 Which of the following are features of both microevolution and macroevolution? (A) mutations only (B) mutations and gene flow only (C) gene flow and genetic drift only (D) mutations gene flow and genetic drift
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Difficulty: C
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2020
QUESTION 21 (2 marks) A count was conducted to determine the number of individuals for five different bird species in a woodland. 55 50 2 45 Cg S 40 '% 35 g 30 S 25 g 20 O g 15 Z 10 5 0 A C D Species Calculate the relative percentage abundance of species B. Show your working.
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Difficulty: B
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2020
QUESTION 22 (4 marks) The following cladogram proposes the evolutionary history of several fish phyla (A—H). A B C D B F G H a) Define the term clade. Circle an example of a clade on the cladogram. [2 marks] b) Which node (1-7) represents the most recent common ancestor for species E and G? [1 mark] c¢) Which two species shared the most recent common ancestor? [1 mark]
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Difficulty: B
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2020
QUESTION 23 (3 marks) Describe differences between r-selected and K-selected species in terms of: * number of offspring parental care and involvement * lifespan. r-selected K-selected Number of offspring Parental care and ivolvement Lifespan
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Difficulty: B
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2020
QUESTION 24 (3 marks) a) Describe what is meant by the genotype of an organism. [1 mark] b) Inherited mutations can affect the genotype of offspring. Describe how this occurs. [2 marks]
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Difficulty: B
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2020
QUESTION 25 (4 marks) The following simplified energy-flow diagram provides the gross productivity figures for producers and herbivores in an ecosystem. plant respiration (including heat) herbivore respiration 16 MJ/m?/year 20 MJ/m?/year Producers i Higher CRESVQESS trophic levels decomposition decomposition 8 MJ/m?/year (waste and death/decay) 5 MJ/m?/year a) Determine the net productivity for the producers and herbivores in this ecosystem. [2 marks] Producers: Netproductivity=___ MJ/m?/year Herbivores: Net productivity=___ MJ/m?/year b) Contrast the outputs of energy for the two trophic levels in the diagram. [2 marks]
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Difficulty: A
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2020
QUESTION 26 (1 mark) Define microevolution.
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Difficulty: C
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2020
QUESTION 27 (4 marks) In a freshwater lake in Africa a species of crab and its snail prey species both exhibit specialisations that are unusual for freshwater species. The crabs possess strong claws with characteristics of marine crabs that crush and peel shells and the snail prey have thick strong shells that resist crushing. a) Identify which pattern of evolution this example represents. [1 mark] b) Describe how the two species may have evolved these characteristics. [3 marks]
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Difficulty: A
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2020
QUESTION 28 (4 marks) Identify two differences between primary and secondary ecological succession. Refer to one example of each type of succession in your response.
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Difficulty: B
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2020
QUESTION 1 (4 marks) a) Explain how a species interaction may be classified as symbiotic. [2 marks] b) Using an example describe the symbiotic relationship of mutualism. [2 marks]
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Difficulty: B
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2020
QUESTION 2 (5 marks) Two species of Paramecium single-celled microorganisms were grown for 4 days in test tubes with a fixed amount of algae added to each tube daily as their food source. The life span for each species ranges from 4—6 hours. Test tubes 1 and 2 each contained a single species and test tube 3 initially contained both species. Live Paramecium population after 4 days (per mL) T w0 T e s w0 a) Identify and describe the ecological principle that relates to these observations. [2 marks] b) Explain the results of the experiment. [3 marks]
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Difficulty: A
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2020
QUESTION 3 (4 marks) Explain the role of the enzymes helicase and DNA polymerase in the process of DNA replication.
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Difficulty: A
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2020
QUESTION 4 (6 marks) An ecologist investigated the species composition of mangrove trees in a natural mangrove forest and an adjacent 30-year-old planted mangrove forest. Three 10 m-wide belt transects were sampled from inland to the sea for each of the forests each covering 100 m on average and placed to cover various strata. The species diversity of Forest A was determined using the Simpson’s Diversity Index (SDI): L B0 WV 7 e | 0|5 ommgoe |5 |0 a) Use the SDI formula to calculate the diversity index for Forest B. Round your answer to two decimal places. [2 marks] b) Identify three reasons why the ecologist used a belt transect rather than line transects or randomly placed quadrats for collecting data to compare these two forests. [3 marks] c) Identify one way in which the ecologist minimised bias in the sampling. [1 mark]
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Difficulty: A
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2020
QUESTION 5 (4 marks) Explain the process of protein synthesis in terms of transcription and translation.
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Difficulty: A
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2020
QUESTION 6 (3 marks) The Bush Stone-curlew is a large mainly nocturnal ground-dwelling bird found on Hamilton Island. Bush Stone-curlews have a wide-ranging diet but prefer to feed on insects molluscs small lizards seeds and occasionally small mammals. During the breeding season nesting birds will search for food in the vicinity of the nest site. a) Identify one factor that would influence carrying capacity on the island. [1 mark] b) Discuss one way the carrying capacity of the Bush Stone-curlew on Hamilton Island could be positively or negatively affected in the future. [2 marks]
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Difficulty: B
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2020
QUESTION 7 (4 marks) Species richness (S) can be determined using the Menhinick’s Index where s is the number of different species represented in a sample and N is the total number of individual organisms in the sample. Species richness (S) = _al JN Sampling of two communities (Community A and Community B) were completed with Community A having S = 0.5 for the six species identified. The results for Community B are shown in the table. Community B e s s [ w Use S to compare Community A with Community B.
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Difficulty: A
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2020
QUESTION 8 (3 marks) In an experiment studying the population dynamics of the house fly two adult house flies were placed in a fly cage with a limited food supply. Population data was collected as summarised in the table. Number of eggs Number of larvae | Number of pupae Number of adults -- Determine the population growth model exhibited by the house fly. Explain your reasoning.
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Difficulty: A
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2020
QUESTION 9 (3 marks) Fossil evidence seems to show that the morphology of the Queensland lung fish has remained relatively unchanged for the past 100 million years. Describe the features of the theory of natural selection to explain how this may have occurred.
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Difficulty: A
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2020
QUESTION 10 (3 marks) Researchers measured the adult beak lengths of an entire population of a species of bird and plotted their results on the graph. After many generations the lengths of the adult beaks were again measured. By comparing this new data to the original data the researchers concluded that the average length of beaks had increased as a result of directional selection. nitial distribution / of beak lengths Frequency 0 5 10 15 20 Beak length (mm) a) Describe directional selection. [2 marks]
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Difficulty: B
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2020
QUESTION 11 (6 marks) The image shows changes in the frequency of a particular gene in a single species of bird leading to a speciation event. These changes have occurred over a period of successive time points (i.e. I IT and III) each separated by approximately 1000 generations. » The letters A B C and D represent separate niches inhabited by the birds. * The arrows depict gene flow between the niches. » The allelic frequency for the gene is shown as f in each niche. 1 111 Draw a conclusion about the type of speciation that has occurred in this population. Explain your reasoning by referring to the information provided in each of the time points.
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Difficulty: A
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2020
QUESTION 1 In mammals inherited mutations can cause variations in the genotype of offspring when they occur in (A) red blood cells. (B) somatic cells. (C) nerve cells. (D) sex cells.
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Difficulty: C
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2021
QUESTION 2 The process of change in the species structure of an ecological community over time is known as (A) cyclic succession. (B) primary succession. (C) ecological succession. (D) secondary succession.
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Difficulty: C
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2021
QUESTION 3 In ocean food webs where phytoplankton is in the first trophic level the second trophic level of zooplankton often has a higher biomass than the phytoplankton at any given time. Which explanation would account for this? (A) (B) © (D) The zooplankton are also able to photosynthesise. Different phytoplankton species are preying on each other. Carnivores in the third trophic level have increased their consumption of zooplankton. The phytoplankton multiply much faster than zooplankton but their lifespan is shorter.
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Difficulty: B
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2021
QUESTION 4 To demonstrate polygenic inheritance of colour in wheat a cross was performed between two intermediate parents (AaBbCc X AaBbCc). Each dominant allele adds a “unit’ of colour to the phenotype. Which graph would depict the number of individuals and number of phenotypes for the cross? A 2 B) =z = 3 2 2 3 3 g g G~ G~ S o 3 z 2 2 Z Z 1 2 3 4 5 6 7 1 2 3 4 5 6 Number of phenotypes for colour Number of phenotypes for colour © = D) = - 5 = 2 3 3 g g = G~ S S 3 3 E g S = Z Z 1 2 3 1 2 Number of phenotypes for colour Number of phenotypes for colour
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Difficulty: B
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2021
QUESTION 5 The graph shows changes for a penguin population and the theoretical carrying capacity of the environment. A Carrying capacity Time Point A on the graph indicates a change in carrying capacity triggered by (A) an increase in penguin pathogens. (B) adecrease in the number of mates available. (C) areduction in space available for nesting sites. (D) an introduced disease affecting the penguins’ survival rates.
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Difficulty: B
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2021
QUESTION 6 The pedigree traces a genetic disease across two generations. Generation [ Key Carrier (not affected) Affected Normal Female O ' Q Generation II Male [l . D The inheritance pattern of this disease can be classified as (A) 1incomplete dominant. (B) autosomal dominant. (C) sex linked. (D) polygenic.
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Difficulty: B
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2021
QUESTION 7 In a long-term study of grasshopper colour in a grassland ecosystem it was found that the most abundant phenotype changed from dark green to straw yellow. dark green straw yellow L7 Population Phenotypic trait (colour) This change in the phenotype is an example of (A) diversifying selection. (B) directional selection. (C) stabilising selection. (D) disruptive selection.
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Difficulty: C
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2021
QUESTION 8 The place where an organism lives is called its (A) niche. (B) habitat. (C) community. (D) environment.
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Difficulty: C
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2021
QUESTION 9 The image represents a gridded quadrat of 20 cm X 20 cm squares used in a plant survey. To calculate cover for a species the surveyor identified each plant species and then counted the number of squares in which the species appeared. Key {% Species A i Species B Not to scale What is the approximate percentage cover of Species A? (A) 22% (B) 44% ©) 53% (D) 58%
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Difficulty: C
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2021
QUESTION 10 The forelimbs of humans dogs birds and whales have a very similar pattern of bones. Human Bird Whale Not to scale The similarity of these structures is best explained by which pattern of evolution? (A) convergent evolution (B) divergent evolution (C) parallel evolution (D) coevolution
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Difficulty: C
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2021
QUESTION 11 In which environment would primary succession occur? (A) fresh lava field (B) harvested wheat crop (C) grassland cleared by fire (D) forest damaged by a cyclone
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Difficulty: C
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2021
QUESTION 12 The phenotypic expression of genes is regulated by (A) transcription factors. (B) random fertilisation. (C) DNA polymerase. (D) helicase.
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Difficulty: C
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2021
QUESTION 13 Which combination of processes demonstrates spermatogenesis? Where process occurs ® four functional haploid gametes one functional gamete with 2-3 polar bodies
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Difficulty: C
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2021
QUESTION 14 Which event could cause a frameshift mutation? (A) non-disjunction during meiosis (B) error during replication (C) Dbase pair substitution (D) heat damage
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Difficulty: B
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2021
QUESTION 15 The table identifies the condition associated with a variety of ploidy changes. Chromosome number (ploidy) Trisomy 23 Klinefelter syndrome For a person who has 45 chromosomes (2n—1) due to an autosomal condition which condition do they have? (A) Cri du chat syndrome (B) Down syndrome (C) Klinefelter syndrome (D) Turner syndrome
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Difficulty: C
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2021
QUESTION 16 A small group of dingoes migrated to a new area and established a population. After several generations the new population showed a different genetic composition from the original population. This is an example of (A) microevolution and gene flow. (B) macroevolution and gene flow. (C) microevolution and genetic drift. (D) macroevolution and genetic drift.
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Difficulty: C
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2021
QUESTION 17 This is a cladogram for seven different classes of organisms (I-VII). Class IT III IV VI VII Which two classes of organisms are most closely related? (A) Tand VII (B) IV and VI (C) TandII (D) IIland IV
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Difficulty: B
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2021
QUESTION 18 Which scenario would create a selection pressure on a given population? (A) change in fur colour (B) change in weather patterns (C) greater resistance to disease (D) 1mproved ability to locate food sources
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Difficulty: C
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2021
QUESTION 19 What is the role of DNA polymerase in DNA replication? (A) breaking the hydrogen bonds that hold the complementary bases of DNA together (B) adding complementary nucleotide bases to the exposed DNA strands (C) sealing the sequence of DNA into two continuous double strands (D) joining RNA primers to the lagging strand of DNA
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Difficulty: C
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2021
QUESTION 20 A keystone species is defined as a species that (A) 1s the top predator in an ecosystem. (B) 1s a major producer in an ecosystem. (C) has a unique and crucial role in an ecosystem. (D) directly influences all species in an ecosystem.
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Difficulty: C
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2021
QUESTION 21 (4 marks) In the Linnaean system of classification the features used to classify living things change according to taxonomic levels. Describe using relevant examples how these features change.
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Difficulty: B
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2021
QUESTION 22 (3 marks) Describe two ways carbon is transformed and one way it is transferred as it cycles through the biotic components of an ecosystem.
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Difficulty: B
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2021
QUESTION 23 (5 marks) To determine the species diversity and species richness of a wetland ecosystem ecologists surveyed communities adjacent to a river using two methods for each community: 1. random species sampling with predetermined grid numbers with 10 quadrats of 4 m? each used for these grids 2. three belt transect lines (50 m X 2 m) across predetermined sampling locations based on strata variation. The map shows the locations of quadrats and transect lines. The table shows survey results. Key m River % Salt marsh Mangroves . Paperbark swamp ‘ Belt transect line [[] Quadrat Not to scale Survey method Belt transect Species richness (number of species) a) Identify three differences between the survey methods used to determine species diversity and species richness in the ecosystem. [3 marks] b) Draw a conclusion about the most suitable method for estimating species diversity and species richness of the communities in this wetland ecosystem. Give a reason to support your conclusion. [2 marks]
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Difficulty: A
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2021
QUESTION 24 (5 marks) The diagram is a hypothetical biomass pyramid for a community. Secondary consumers 76 kg Primary consumers 1520 kg Producers 15200 kg Not to scale a) Contrast the efficiency of the biomass transfers between each level of the pyramid. [3 marks] b) Explain the difference in biomass transfer efficiency identified in Question 24a). [2 marks]
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Difficulty: B
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2021
QUESTION 25 (3 marks) In blood group inheritance in humans three alleles (i I** and I®) determine blood type which can be type O A B or AB. It is known that: o allele I* produces type A and is co-dominant with allele 1B which produces type B « allele 1 produces type O « alleles I* and I® are dominant over allele i. A father who i1s heterozygous type A and a mother who is heterozygous type B have children. Predict the likely frequency of phenotypes for their offspring. Show your working.
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Difficulty: A
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2021
QUESTION 26 (4 marks) a) State the three components of a DNA nucleotide. [1 mark] b) Describe the steps involved in DNA profiling. [3 marks]
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Difficulty: B
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2021
QUESTION 27 (3 marks) The table shows the percentage sequence similarity for three different parts of a gene found in four different eukaryotic species. The data was obtained by comparing DNA from one member of each species to Species A. From this data a proposed phylogenetic tree was produced. 100% 100% 100% e e | e | w o [ [ | D A ™ a Determine whether the phylogenetic tree has been drawn correctly based on the DNA comparison. Explain your reasoning.
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Difficulty: A
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2021
QUESTION 28 (3 marks) The graph depicts the population change of a species after it is introduced into a previously disturbed environment. Phase B Phase A Population size Time Referring to Phase A and Phase B determine the population growth model for the species.
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Difficulty: B
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2021
QUESTION 1 (4 marks) Explain how one abiotic and one biotic factor will affect the population of mosquito larvae in a freshwater pond.
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Difficulty: B
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2021
QUESTION 2 (3 marks) a) Explain the difference between exons and introns. [2 marks] b) State a function of telomeres. [1 mark]
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Difficulty: B
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2021
QUESTION 3 (3 marks) In coastal areas and deserts bare sand dunes may be colonised by plants such as members of the Poaceae family (grasses). Identify three features of these plants that make them effective colonisers.
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Difficulty: C
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2021
QUESTION 4 (2 marks) Explain the purpose of the polymerase chain reaction (PCR) process and provide an example of its application.
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Difficulty: B
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2021
QUESTION 5 (6 marks) Meiosis ensures that a wide range of genetic combinations occurs during the formation of gametes. The diagrams show two processes that occur during meiosis. Process 1 Duplicated homologous chromosomes Process 2 Duplicated chromosomes . Membrane / . Describe the two processes shown in the diagrams and how they contribute to genetic variation in gametes. Name and description of process I: Name and description of process 2:
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Difficulty: A
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2021
QUESTION 6 (2 marks) The term species could be defined as ‘one group of individuals that actually or potentially interbreed 1n nature’. Identify two limitations of this definition.
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Difficulty: B
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2021
QUESTION 7 (3 marks) Koalas were once widespread in Australia. Due to a variety of factors their population decreased and fragmented into small pockets forcing them to inbreed. They have recently been hit by devastating epidemic diseases. Explain why koalas face an increased extinction risk from disease.
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Difficulty: B
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2021
QUESTION 8 (3 marks) Australia has many bird species that have evolved to be largely dependent on mangroves. These species are patchy in their distribution because of: « the island-like distribution of their habitat * exclusion by possible competitors » geographical barriers. Identify and describe the mode of speciation that may have caused diversity in mangrove bird species.
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Difficulty: B
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2021
QUESTION 9 (3 marks) A computer simulation was used to observe genotypic changes in the gene pool of 20 randomly selected rabbits. The simulation was set with these parameters: each rabbit’s coat colour was either black or white » black alleles were dominant; white alleles were recessive « the number of rabbits was constant in each generation and breeding was random throughout the population « an environmental factor was chosen in the simulation to provide selection pressure. The table shows the results of the simulation at the start and after 20 generations. Initial population genotypes Population genotypes after 20 generations BB BB BB BB BB BB BB BB Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb Contrast the initial allele frequency with the allele frequency after 20 generations to draw a conclusion about the effect of the selection pressure on the rabbit population.
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Difficulty: A
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2021
QUESTION 10 (3 marks) Describe three ways DNA occurs in cells.
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Difficulty: C
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2021
QUESTION 11 (2 marks) Adult skeletal stem cells differentiate into intermediate cells and later into specialised bone tissue types. Skeletal stem cell Intermediate cell Cfi\//ifm@ Compact bone / Cartilage The table shows how three transcription factors (A B and C) affect bone tissue formation. Transcription Intermediate cell Cartilage Compact bone factor role Actlvators Explain the effect of transcription factors on gene expression and tissue formation. Use an example from the table to support your answer.
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Difficulty: A
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2021
QUESTION 12 (5 marks) An investigation compared mangrove species diversity for two areas of different size in the same catchment. The table shows species population counts for each area. Grey mangrove Red mangrove Yellow mangrove 88 (? Total species count a) Calculate Simpson’s diversity index for Area 2. Show your working. SD]_I_[M N(N —1) (correct to two decimal places) b) Using your answer for Question 12a) compare the diversity of the two areas. [2 marks] [3 marks]
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Difficulty: A
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2021
QUESTION 13 (3 marks) The data shows changes in relative abundance of ground cover biomass and species diversity for an abandoned sand mine site over time. Key D Bare ground QGrasses (e.g. spinifex tussock grass) . Seedlings/shrubs (e.g. banksia eucalypt) Leaf litter I:] Mature trees Abundance Key D Biomass — Species diversity Biomass (kg/mz) Time Based on the information provided predict whether further ecological succession would occur in this community. Justify your answer with two relevant reasons.
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Difficulty: A
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2021
QUESTION 1 What is the molecular unit of heredity? (A) gene (B) genome (C) nucleotide (D) chromosome
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Difficulty: C
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Paper 1
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2022
QUESTION 2 Which stage of making recombinant DNA requires DNA ligase? (A) cutting (B) joining (C) 1solation (D) transformation
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Difficulty: C
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2022
QUESTION 3 A survey of grasshopper species was conducted across four eucalypt communities. Counts were conducted and the average abundance per 400 m? recorded. Grasshopper species (A-F) ) S N Which community has both the highest species richness and highest evenness for grasshoppers? (A) 1 (B) II (©) I (D) 1V
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Difficulty: C
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2022
QUESTION 4 The graph shows the effect of a selection pressure on a hypothetical population. Phenotype Key [ ] Before the selection pressure B 20 generations later Number of individuals Which mode of phenotypic selection corresponds with the data? (A) negative (B) disruptive (C) stabilising (D) directional
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Difficulty: C
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2022
QUESTION 5 A researcher captured marked and released 36 frogs. The following day they captured 24 frogs and 18 were marked. Calculate the approximate size of the frog population using the Lincoln index: N = Mnj (A) 27 (B) 48 (C) 54 (D) 60
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Difficulty: C
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2022
QUESTION 6 The role of helicase in DNA replication is to (A) 1nitiate the process by binding to recognition sites along the template strand. (B) add complementary bases to the template strand. (C) unwind and separate DNA strands. (D) join DNA strands together.
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Difficulty: C
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2022
QUESTION 7 What 1s used directly by plants for protein synthesis? (A) nitrite NO (B) mnitrate NOy~ (C) ammonia NH; (D) atmospheric nitrogen N
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Difficulty: B
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2022
QUESTION 8 The graph shows how the populations of two species in an ecosystem change over time. Key Species X ---- Species Y 9] 5 . p— c < &0 — o (A 8 l/ \ O / \ O / \ g / \ B / \ Z JER / \ ’ / \ / Y / \ / \ / \ / \ / \\ / / )/ . / 1 277G 7 \ /l —s\\ ’ / \\— N - \\ ’ ~ Time Which species interaction is represented? (A) predation where species X preys on species Y (B) predation where species Y preys on species X (C) competition where species X outcompetes species Y (D) competition where species Y outcompetes species X
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Difficulty: B
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2022
QUESTION 9 Polygenic inheritance involves multiple (A) alleles for a single gene. (B) genes with the same alleles. (C) genes coding for a single characteristic. (D) characteristics resulting from a single gene.
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Difficulty: C
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2022
QUESTION 10 Wings in birds bats and pterosaurs are phenotypically similar though they belong to different families and do not have a common ancestor with the trait. While the general morphology is similar the structure and organisation of each wing is different. This is an example of (A) coevolution. (B) parallel evolution. (C) divergent evolution. (D) convergent evolution.
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Difficulty: C
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2022
QUESTION 11 Evolutionary relationships were investigated by sequencing a section of protein from five different species. Each letter represents an amino acid. Species I D Species 11 D Species I11 D Species IV D Species V D It can be inferred that Species I 1s most closely related to (A) Species II. (B) Species III. (C) Species IV. (D) Species V.
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Difficulty: B
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2022
QUESTION 12 Speciation occurs when (A) the gene pool of an existing species becomes too small to support a viable population. (B) selection pressures cause significant changes to the allele frequencies of a population. (C) genetic drift is no longer occurring within populations. (D) gene flow is no longer occurring between populations.
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Difficulty: C
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2022
QUESTION 13 An error during DNA replication resulted in the following change to mRNA transcripts. mRNA before | AUGAAGUUUGGCAUC ... (continued) mRNA after | AUGAAGUUUGCAUCG ... (continued) The DNA replication error most likely involved (A) (B) ©) (D) deletion of cytosine. insertion of guanine. substitution of uracil with guanine. substitution of guanine with cytosine.
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Difficulty: B
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2022
QUESTION 14 Prior to fertilisation a secondary oocyte will arrest at which stage of meiosis? (A) prophase I (B) prophase II (C) metaphase I (D) metaphase 11
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Difficulty: B
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2022
QUESTION 15 The environment’s influence on gene expression can be investigated by comparing the rate of concordance in monozygotic (identical) and dizygotic (non-identical) twins. Concordance occurs when both twins express a trait. Strong environmental influence is suspected when concordance is (A) higher in monozygotic twins. (B) only observed in dizygotic twins. (C) only observed in monozygotic twins. (D) similar in monozygotic and dizygotic twins.
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Difficulty: C
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2022
QUESTION 16 If each shape represents a different species which diagram shows the common assumptions of cladistics? (A) ] (B) /\ 0 0 ] /\ Time Time (®) A (D) D - h 3 O A\ Time Time
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Difficulty: C
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2022
QUESTION 17 Students used quadrats to investigate biodiversity in a grassland community with scattered distribution of plant species. The students agreed on a counting criteria for each quadrat to (A) reduce the time taken to count the different species. (B) minimise statistical uncertainty. (C) ensure all strata were sampled. (D) minimise bias.
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Difficulty: C
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2022
QUESTION 18 The competitive exclusion principle applies to different species occupying the same (A) niche. (B) habitat. (C) environment. (D) trophic level.
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Difficulty: C
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2022
QUESTION 19 The graph shows the effect of light intensity on the germination success of seeds from four plant species. 100 . .......... Species I 80 g = 60 = < N — - Species II 40 O SN Species 111 201 T e . eec® eec® ...... . ) e . e Species IV Light intensity Which is most likely to be a pioneer species? (A) 1 (B) 1I (C) I (D) 1V
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Difficulty: C
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2022
QUESTION 20 A section of DNA is made up of two strands I and II. Base Strand I Strand II composition | composition owe || e | e wmive | [0 It can be inferred that (A) strand I contains 25% cytosine. (B) strand I contains 32% adenine. (C) strand II contains 29% thymine. (D) strand II contains 71% adenine.
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Difficulty: B
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2022
QUESTION 21 (2 marks) Describe two reproductive strategies used to distinguish K-strategists from r-strategists. Strategy 1: Strategy 2:
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Difficulty: C
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2022
QUESTION 22 (2 marks) Explain how two abiotic factors affect the distribution of species in an ecosystem. Ecosystem: Abiotic factor 1: Abiotic factor 2:
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Difficulty: C
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2022
QUESTION 23 (3 marks) Compare microevolution and macroevolution.
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Difficulty: B
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2022
QUESTION 24 (2 marks) Explain two ways that classifying ecosystems allows for effective management of old-growth forests.
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Difficulty: B
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2022
QUESTION 25 (4 marks) Severe weather events have caused widespread loss of seagrass in meadows off Location A. Seagrasses have the capacity to recover from weather-associated disturbances and return to pre-impact levels within 4 to 60 months. Deep-water meadows have a higher rate of recovery than shallow-water meadows. o Location A Key B Shallow-water meadows [ Deep-water meadows D Sea 0 25 B Land ; L} Lan Kilometres Describe how stratified sampling could be used to study how seagrass meadows off Location A recover after a severe weather event. Identify a surveying technique and purpose for the study in your response.
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Difficulty: A
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2022
QUESTION 26 (4 marks) Karyotypes for two human gametes are shown. Karyotype A (sperm cell) Karyotype B (egg cell) a) Identify which cell exhibits aneuploidy. Refer to evidence from the karyotype. [1 mark] b) Explain how this chromosome abnormality may have occurred. [2 marks] This table lists some genetic conditions resulting from chromosomal abnormalities. Cri du chat syndrome Trisomy 18 Edwards syndrome c) Predict which genetic condition would occur if the two gametes produced a zygote. [1 mark]
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Difficulty: B
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2022
QUESTION 27 (2 marks) Explain the purpose of gel electrophoresis in DNA profiling.
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Difficulty: B
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2022
QUESTION 28 (3 marks) In 1950 the myxoma virus was released into Australian pest rabbit populations to reduce their numbers. The resulting disease myxomatosis initially wiped out 95% of the rabbit population; however it quickly became less effective as a population control measure. This graph shows the frequency of myxomatosis resistance in Australia’s rabbit population from 1949 to 1956. 100 90 S 5 80 o < = 70 5 2 60 & £ 50 o % = 40 (- o > 30 a 3 g 20 [ 10 'v . — | 1949 1950 1951 1952 1953 1954 1955 1956 Year Use evidence from the graph and the principles of natural selection to explain how myxomatosis became ineffective as a population control measure.
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Difficulty: B
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2022
QUESTION 1 (3 marks) This phylogenetic tree uses horizontal distance to represent genetic difference. Species A Species B Species C Species D L 1 unit Scale 1 unit = nucleotide difference a) Infer which species is most closely related to species B. Explain your reasoning. [2 marks] b) Determine the genetic difference between species A and D. [1 mark]
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Difficulty: B
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Paper 2
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2022
QUESTION 2 (4 marks) This 1s a biomass pyramid for a grassland community. Not to scale a) Calculate the percentage energy transfer between the first two trophic levels. Show your working. [2 marks] b) Explain the loss of biomass between trophic levels. [2 marks]
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Difficulty: B
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2022
QUESTION 3 (4 marks) A glacier has retreated leaving a large amount of gravel small rocks sand and mud. a) Explain the steps of succession that would occur if the glacier continues to retreat. [3 marks] b) Identify the type of ecological succession. [1 mark]
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Difficulty: B
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2022
QUESTION 4 (1 mark) Define keystone species.
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Difficulty: C
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2022
QUESTION 5 (5 marks) a) Describe the roles of messenger RNA and transfer RNA in protein synthesis. [2 marks] b) Explain how transcription factors control cell differentiation using an example. [3 marks]
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Difficulty: A
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2022
QUESTION 6 (5 marks) An environmental report identified overexploitation habitat destruction and pollution as human activities affecting biodiversity in Australia. The tables show the estimated impact of each activity in 2011 and 2016. 2011 2016 Assessment grade Confidence Assessment grade Very Very H ac‘ggfiis high | High | Low | low high | High | Low impact 1mpact 1 pact 1 pact grade trend impact 1mpact 1 pact 1 pact grade trend Improving Very low impact: Few if any . Adequate: Adequate high- species and/or ecosystems are quality evidence and high level Getting worse suffering substantial adverse effects of consensus from this pressure E Biable Low impact: A small proportion Somewhat adequate: Adequate of species and/or ecosystems are high-quality evidence or high suffering substantial adverse effects level of consensus from this pressure High impact: A significant Limited: Limited evidence or proportion of species and/or limited consensus ecosystems are suffering substantial adverse effects from this pressure Very high impact: A large G Very limited: Limited evidence proportion of species and/or and limited consensus ecosystems are suffering substantial adverse effects from this pressure a) Explain how one human activity identified in the tables could reduce biodiversity. [1 mark] b) Predict which human activities will have the highest and lowest impact on biodiversity in 2023. Explain your reasoning using evidence from the tables. [4 marks] Highest impact: Lowest impact:
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Difficulty: A
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2022
QUESTION 7 (6 marks) The graph shows the population of bacteria in a Petri dish over time. 12000 10000 8000 6000 Population 4000 2000 0 50 100 150 200 250 300 350 Time (minutes) a) Identify the mode of population growth. [1 mark] b) Determine the carrying capacity under these conditions. [1 mark] Conditions were modified at 380 minutes and the population continued to be monitored. Results are shown. 25000 20000 15000 Population 10000 5000 0 100 200 300 400 450 Time (minutes) c) Identify two modifications that could cause this change. Explain your reasoning. [4 marks]
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Difficulty: B
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2022
QUESTION 8 (3 marks) Over time the South African cheetah population has suffered drastic reduction due to periodic droughts disease and hunting. Currently only small isolated populations of cheetahs exist in the wild. Explain in terms of genetic diversity why cheetah populations are now on the verge of extinction.
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Difficulty: B
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2022
QUESTION 9 (3 marks) The biological species concept defines species as a group of organisms that can interbreed to produce fertile offspring. a) Identify another method for defining a species. [1 mark] b) Describe one limitation of the biological species concept and one limitation of the method identified in Question 9a). [2 marks]
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Difficulty: B
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2022
QUESTION 10 (3 marks) In fruit flies eye colour is a sex-linked trait inherited on the X chromosome. The red-eye allele (R) is dominant over the white-eye allele (r). A red-eyed male and white-eyed female have 50 offspring. Use a Punnett square to predict the number of male and female offspring and their eye colour.
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Difficulty: B
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2022
QUESTION 11 (8 marks) Allele frequencies were monitored in two large populations of field mice from neighbouring forests over a 10-year period. Results are shown. Forest X [ e s a) Calculate the allele frequencies for forest Y in 2018. Show your working. [2 marks] b) Identify temporal trends in allele frequency for forests X and Y and infer reasons for the observed differences. [6 marks]
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Difficulty: A
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2022