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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.
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
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.
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
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]
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
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]
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
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.
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.
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.
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
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.
QUESTION 21 (2 marks) Describe two reproductive strategies used to distinguish K-strategists from r-strategists. Strategy 1: Strategy 2:
QUESTION 24 (2 marks) Explain two ways that classifying ecosystems allows for effective management of old-growth forests.
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.
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]
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]
QUESTION 1 Female Komodo dragons (Varanus komodoensis) in the absence of a mate can produce offspring in which the growth and development of the embryo can occur without the joining of gametes. Identify which of the following methods of reproduction would be used to classify this species. (A) Dbinary fission (B) parthenogenesis (C) internal fertilisation (D) external fertilisation
QUESTION 2 An investigation surveyed a land zone that had ¢ high precipitation rates e an open canopy forest with tall emergents and e a well-developed understorey of ferns palms and sclerophyll shrubs. The dominant forest tree species were e flooded gum (Eucalyptus grandis) e Sydney blue gum (Eucalyptus saligna) e red mahogany (Eucalyptus resinifera) and e brush box (Lophostemon confertus). A dominant vegetation community classification system would classify this ecosystem as a (A) rainforest. (B) eucalypt woodland. (C) eucalypt open forest. (D) wet eucalypt open forest.
QUESTION 12 Which symbiotic interaction occurs when one species is harmed and the other species benefits? (A) parasitism (B) mutualism (C) amensalism (D) commensalism
QUESTION 1 The biological species concept defines species as a group of organisms (A) with a common set of alleles. (B) descended from a common ancestor. (C) occupying the same niche or adaptive zone. (D) that can interbreed to produce fertile offspring.
QUESTION 2 Species classified as K-strategists (A) often live in unstable habitats. (B) exhibit an exponential rate of reproduction. (C) reach sexual maturity later than r-strategists. (D) are first to colonise a new environment created by a disturbance.
QUESTION 23 (3 marks) Mistletoe is the common name for plants that have a close and long-term interaction with a host tree. In Australia mistletoe frequently live on eucalyptus trees penetrating the bark with their modified root systems to access water and nutrients from the xylem. This can restrict nutrient flow in the host tree and may cause parts of its branches to die. a) Identify the species interaction demonstrated in this scenario. [1 mark] b) Explain how this relationship differs from predation. [2 marks]
QUESTION 5 (3 marks) Nucleic acid sequences were used to investigate evolutionary relationships between four species. Species Nucleic acid sequence GACCGCATTTACGTA GACGTCATATCCGTA a) b) GACCGCATTTCCGTA GACGGCATATCCGTA Explain how data from conserved molecular sequences can be used to estimate time since divergence. Use the data to infer species I-IV in the cladogram. Species Species Species Species I: B. bartonus II: [2 marks] [1 mark] Il:
QUESTION 1 (6 marks) The profile diagram shows a representative section of an ecosystem. Height (m) Distance (m) This table can be used to classify ecosystems based on Specht’s classification system. Foliage cover of tallest plant layer Dense (70—100%) Mid-dense (30—70%) | Sparse (10-30%) Tall closed-forest Tall open-forest Tall woodland Closed-forest Woodland Low closed-forest Low woodland Closed-scrub Tall shrubland Classify this ecosystem. [1 mark] Describe how field data could be collected for the purpose of classifying this ecosystem using Specht’s classification system. Include at least one strategy to minimise bias. [3 marks] Explain how Specht’s classification system could be used to monitor how the ecosystem recovers after a logging event that removes 80% of trees from the tallest plant layer. [2 marks]
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