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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.
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%
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]
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.
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.
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.
QUESTION 1 (4 marks) Explain how one abiotic and one biotic factor will affect the population of mosquito larvae in a freshwater pond.
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
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]
QUESTION 3 In 1978 a population of a migratory shore bird was estimated at 90 000 individuals. An analysis of monitoring data in 2018 showed the population is now at 50 000. The change in population growth for this species is (A) —29% (B) —44% (C) —55% (D) —80%
QUESTION 17 Which of the figures below represents a logistic population growth of a species over time? (A) Population Time (B) Population Time ©) Population Time (D) Population Time
QUESTION 3 The table provides population data for a species of fairy-wren. Year Population on Births Deaths Immigration | Emigration 1st January 2022 15200 200 7600 | 4310 | The population growth rate in 2022 was closest to (A) 17% (B) 27% (C) 55% (D) 73%
QUESTION 20 The capture—recapture method and Lincoln index (N = ant) were used to monitor a population of m platypuses over a four-year period. Experimental findings are shown. 26 24 22 20 18 16 14 Number of platypuses 2019 2020 2021 2022 Year The table shows data from one year of the study. Number of individuals captured and marked in first sampling Number of individuals captured in second sampling Number of recaptured individuals marked When was the data in the table collected? (A) 2019 (B) 2020 (C) 2021 (D) 2022
QUESTION 26 (3 marks) Wedge-tailed eagles are large birds that reside in tall trees where they build nests for their young. They often feed on ground-dwelling herbivores such as kangaroos and rabbits. The graph shows the number of wedge-tailed eagles observed in an ecosystem over time. 800 700 | Sf | | 600 LAY ! [ 300 200 / : 3 : 100 : 0 2010 2012 2014 2016 2018 2020 2022 Number of eagles Year a) Determine the carrying capacity of wedge-tailed eagles in this ecosystem. [1 mark] b) Explain how a change to one abiotic factor could reduce the carrying capacity. [2 marks]
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