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 9 of 17
- Q2 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 2 Which form of inheritance usually determines traits that display continuous phenotypic variation? (A) polygenic (B) sex-linked (C) multiple allele (D) incomplete dominance
- Q3 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 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.
- Q4 · 2020 QCAA · Paper 1 · 1 markBiodiversity and populationsQUESTION 4 The following information includes: • a key that is used to classify the types of alpine and subalpine grassland habitats • a table of abiotic and biotic data obtained from a habitat survey. Alpine and subalpine grasslands Habitat classification Moss-and-lichen- Moss-and-lichen-dominated? Yes dominated mountain summit No Alpine and subalpine Yes…
- Q5 · 2020 QCAA · Paper 1 · 1 markContinuity of life on EarthQUESTION 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. 1900 families 900 living Number of marine families 800 today 700 600 500 400 300 200 100 0 Carboniferous Precambrian Ordovician Cretaceous Paleogene Cambrian Devonian Neog…
- Q6 · 2020 QCAA · Paper 1 · 1 markFunctioning ecosystems and successionQUESTION 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 g…
- Q7 · 2020 QCAA · Paper 1 · 1 markFunctioning ecosystems and successionQUESTION 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 (A) Increasing Decreasing (B) Decreasing Increasing (C) Increasing Increasing (D) Decreasing Decreasing
- Q8 · 2020 QCAA · Paper 1 · 1 markFunctioning ecosystems and successionQUESTION 8 The table shows the daily energy input and output for a typical leaf. Process Energy value (kJ) Incident sunlight 42.3 Evaporation 31.2 Heat loss (radiation) 2.1 Reflection of sunlight 6.1 Transmission of sunlight 2.1 Calculate the daily net energy stored by the leaf. (A) 0.8 kJ (B) 5.0 kJ (C) 36.2 kJ (D) 73.5 kJ
- Q9 · 2020 QCAA · Paper 1 · 1 markBiodiversity and populationsQUESTION 9 The table provides population statistics for a species of tree kangaroo in northern Queensland. Year Births Deaths Immigration Emigration Final population 2016 253 175 153 131 1100 2017 290 167 182 140 Determine the population growth rate for tree kangaroos in 2017. (A) 14.6% (B) 15.0% (C) 26.5% (D) 86.9%
- Q10 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 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.
- Q11 · 2020 QCAA · Paper 1 · 1 markBiodiversity and populationsQUESTION 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
- Q12 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 12 In the structure of DNA, adenine pairs with which other base? (A) uracil (B) guanine (C) cytosine (D) thymine
- Q13 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 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
- Q14 · 2020 QCAA · Paper 1 · 1 markContinuity of life on EarthQUESTION 14 One of the common assumptions in cladistics is that (A) not all organisms are related by descent. (B) the characteristics of organisms in a population stay the same over time. (C) new kinds of organisms may arise when existing populations divide into two groups. (D) the more shared characteristics two organisms have, the more closely related…
- Q15 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 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 (F0) generation and the subsequent (F1) generation. 1.0 Key 0.…
- Q16 · 2020 QCAA · Paper 1 · 1 markFunctioning ecosystems and successionQUESTION 16 The figures show the original distribution zone of Species I and some possible distribution zones of Species I after the introduction of Species II. Species II has a competitive advantage over Species I; however, it does not tolerate areas of lower rainfall. Before After original possible distribution zone distribution zones Rainfall Rainfall D A…
- Q17 · 2020 QCAA · Paper 1 · 1 markGenetics and heredityQUESTION 17 The table identifies the condition associated with a variety of ploidy changes. Chromosome number ploidy Condition name Monosomy 5 Cri du chat syndrome Trisomy 21 Down syndrome Trisomy 23 Klinefelter syndrome Monosomy 23 Turner syndrome For a person with XXY sex chromosomes, which condition would they have? (A) Cri du chat syndrome (B) Down syn…
- Q18 · 2020 QCAA · Paper 1 · 1 markContinuity of life on EarthQUESTION 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/genoty…
- Q19 · 2020 QCAA · Paper 1 · 1 markContinuity of life on EarthQUESTION 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 Human Lys Glu His Ile Val Glu Phe Lys (A) Lys…
- Q20 · 2020 QCAA · Paper 1 · 1 markContinuity of life on EarthQUESTION 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
- Q21 · 2020 QCAA · Paper 1 · 2 marksBiodiversity and populationsQUESTION 21 (2 marks) A count was conducted to determine the number of individuals for five different bird species in a woodland. 55 50 45 Number of individuals 40 35 30 25 20 15 10 5 0 A B C D E Species Calculate the relative percentage abundance of species B. Show your working.
- Q22 · 2020 QCAA · Paper 1 · 4 marksContinuity of life on EarthQUESTION 22 (4 marks) The following cladogram proposes the evolutionary history of several fish phyla (A–H). A B C D E F G H 6 7 1 5 2 4 3 a) Define the term clade. Circle an example of a clade on the cladogram. [2 marks] Note: If you make a mistake on the cladogram, cancel it by ruling a single diagonal line through your work and use the additional cladog…
- Q23 · 2020 QCAA · Paper 1 · 3 marksBiodiversity and populationsQUESTION 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 involvement Lifespan
- Q24 · 2020 QCAA · Paper 1 · 3 marksGenetics and heredityQUESTION 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]
- Q25 · 2020 QCAA · Paper 1 · 4 marksFunctioning ecosystems and successionQUESTION 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/m2/year 20 MJ/m2/year Producers Higher Herbivores gross productivity trophic levels = 52 MJ/m2/year decomposition decomposition 8 MJ/m2/year (w…