Biology questions and solutions

Browse original practice and official past-paper questions. Each question has its own link, with its source and worked solution.

385 questions · Page 6 of 17

1. Q10 · 2022 QCAA · Paper 1 · 1 mark
   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) co…
   Continuity of life on Earth
2. Q11 · 2022 QCAA · Paper 1 · 1 mark
   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 E V G W E A L G R L V S Species II D E V G W E G L G R A V S Species III D E A G S E G L A R L E S Species IV D E V G S E G L G R L E S Species V D E V G W E A L A R L V S It can be inferre…
   Continuity of life on Earth
3. Q12 · 2022 QCAA · Paper 1 · 1 mark
   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.
   Continuity of life on Earth
4. Q13 · 2022 QCAA · Paper 1 · 1 mark
   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) deletion of cytosine. (B) insertion of guanine. (C) substitution of uracil with guanine. (D) substitution of guanine with cytosi…
   Genetics and heredity
5. Q14 · 2022 QCAA · Paper 1 · 1 mark
   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 II
   Genetics and heredity
6. Q15 · 2022 QCAA · Paper 1 · 1 mark
   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…
   Genetics and heredity
7. Q16 · 2022 QCAA · Paper 1 · 1 mark
   QUESTION 16 If each shape represents a different species, which diagram shows the common assumptions of cladistics? (A) (B) Time Time (C) (D) Time Time
   Continuity of life on Earth
8. Q17 · 2022 QCAA · Paper 1 · 1 mark
   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.
   Biodiversity and populations
9. Q18 · 2022 QCAA · Paper 1 · 1 mark
   QUESTION 18 The competitive exclusion principle applies to different species occupying the same (A) niche. (B) habitat. (C) environment. (D) trophic level.
   Functioning ecosystems and succession
10. Q19 · 2022 QCAA · Paper 1 · 1 mark
    QUESTION 19 The graph shows the effect of light intensity on the germination success of seeds from four plant species. 100 Species I 80 Germination (%) 60 Species II 40 Species III 20 Species IV 0 Light intensity Which is most likely to be a pioneer species? (A) I (B) II (C) III (D) IV
    Biodiversity and populations
11. Q20 · 2022 QCAA · Paper 1 · 1 mark
    QUESTION 20 A section of DNA is made up of two strands, I and II. Base Strand I Strand II composition composition adenine cytosine 25% guanine 14% thymine 29% 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. References Question 8 Modified fro…
    Genetics and heredity
12. Q21 · 2022 QCAA · Paper 1 · 2 marks
    QUESTION 21  (2 marks) Describe two reproductive strategies used to distinguish K-strategists from r-strategists. Strategy 1: Strategy 2:
    Biodiversity and populations
13. Q22 · 2022 QCAA · Paper 1 · 2 marks
    QUESTION 22  (2 marks) Explain how two abiotic factors affect the distribution of species in an ecosystem. Ecosystem: Abiotic factor 1: Abiotic factor 2:
    Biodiversity and populations
14. Q23 · 2022 QCAA · Paper 1 · 3 marks
    QUESTION 23  (3 marks) Compare microevolution and macroevolution.
    Continuity of life on Earth
15. Q24 · 2022 QCAA · Paper 1 · 2 marks
    QUESTION 24  (2 marks) Explain two ways that classifying ecosystems allows for effective management of old-growth forests.
    Biodiversity and populations
16. Q25 · 2022 QCAA · Paper 1 · 4 marks
    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. Location A Key Shallow-water meadows D…
    Functioning ecosystems and succession
17. Q26 · 2022 QCAA · Paper 1 · 4 marks
    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 abnormaliti…
    Genetics and heredity
18. Q27 · 2022 QCAA · Paper 1 · 2 marks
    QUESTION 27  (2 marks) Explain the purpose of gel electrophoresis in DNA profiling.
    Genetics and heredity
19. Q28 · 2022 QCAA · Paper 1 · 3 marks
    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…
    Continuity of life on Earth
20. Q1 · 2022 QCAA · Paper 2 · 3 marks
    QUESTION 1  (3 marks) This phylogenetic tree uses horizontal distance to represent genetic difference. Species A Species B Species C Species D 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]
    Continuity of life on Earth
21. Q2 · 2022 QCAA · Paper 2 · 4 marks
    QUESTION 2  (4 marks) This is a biomass pyramid for a grassland community. 11.5 g/m2 36 g/m2 900 g/m2 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]
    Functioning ecosystems and succession
22. Q3 · 2022 QCAA · Paper 2 · 4 marks
    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]
    Functioning ecosystems and succession
23. Q4 · 2022 QCAA · Paper 2 · 1 mark
    QUESTION 4  (1 mark) Define keystone species.
    Functioning ecosystems and succession
24. Q5 · 2022 QCAA · Paper 2 · 5 marks
    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]
    Genetics and heredity