Explain ONE possible advantage of the difference in ear size in the particular environment of each fox. 19 (a) (i) Give ONE example of a malfunction of the human immune system that causes a specific disease. ii).
SECTION II—ELECTIVES
The Australian Environment
Choose ONE cartoon and explain how it illustrates ONE of the factors that may have led to the current distribution of marsupials in Australia.
A family of small South American insect-eating marsupials, the Microbiotheriidae, has had its DNA sequenced. How could this evidence be used to support theories about the current distribution of native marsupials in South America and Australia.
A survey was undertaken to quantify the vegetation of plant communities in the Myall Lakes area of NSW. From the edge of the lake to the top of a ridge 280 m away, a transect was laid. Justify why you will measure these variables. d) Tea tree The paper tree (Melaleuca quinquenervia) and the coast oak (Casuarina equisetifolia) were introduced in Florida, USA, where they are replacing natural vegetation.
After thirty years of European settlement, a number of native species west of the Great Dividing Range mountains are thought to have disappeared. How might European settlements east of this range have affected the number of native species west of the range. ii). Include a list of equipment needed in your answer. ii) Name ONE advantage and TWO potential problems of the method you chose to determine the distribution of the animal in part (i) 2. iii) Humans accidentally introduce a disease that destroys the animal population described in part (i) 2.
Describe TWO factors that could explain the increase in the extinction rate during this period. f) (i) As an ecologist, you have been assigned to investigate an ecosystem on an island uninhabited by humans. Include a list of necessary equipment with your answer. ii) State ONE advantage and TWO potential problems of the method you chose to determine the distribution of the animal in part (i) 2. iii) Humans accidentally introduce a disease that destroys the animal population as described in part (i) 2. State ONE potential short-term impact and ONE potential long-term impact on the ecosystem. g) Mangrove trees grow in the tidal zone in estuaries. Use only the information in the diagram to describe the tree's life cycle. ii).
Structure and Function of Cells and Tissues
In which part of a chloroplast will chlorophyll be found? ii) Explain how, during photosynthesis, the interaction of light with chlorophyll results in the formation of:. iii). Name ONE other compound that is required. iv) Some organisms, e.g. chemosynthetic bacteria live underground and do not use light to generate the compounds needed to fix carbon dioxide. This is called the "folded" state. i) Explain why the enzyme must be in the folded state to convert substrate to product. ii) Predict the effect of changing the amino acid sequence in the polypeptide.
This is called the 'folded' state. i) Explain why the enzyme must be in the folded state to convert substrate into product. ii) Predict the effect of changing the sequence of amino acids in the polypeptide. e) (i) Explain what is meant by the term differentiation. ii) The diagram shows a growing root tip.
Control and Coordination
How does a nerve fiber transmit information that allows muscle fibers to vary the strength of contraction. iv) Explain how nerve impulses can be transmitted in both directions along an axon, whereas transmission can only occur in one direction across a synapse.
At what point (A, B, C, or D) does depolarization of the nerve impulse begin (marked Xin on the graph). ii) Which process maintains the balance of potassium and sodium ions after the membrane potential returns to its resting level. iii). Both possess hormones that are involved in communication between cells. i) Describe ONE major difference between plant and animal hormones with respect to:. ii) Name a plant hormone involved in phototropism. iii) Describe the effect of this hormone on plant cells. iv). Include details of feedback mechanisms that maintain organ or tissue function.
Give TWO reasons for this difference. ii) Name an organ or tissue, and a reaction thereof, which is coordinated or controlled by BOTH the nervous and endocrine systems. iii) Draw a labeled diagram to illustrate how these two systems control the function of this organ or tissue. Why do these artificial hormones work specifically with the target cell and not with other types of cells. f) The diagram shows two different types of neurons. i) Name the structures labeled W,X,Yand Zon neuronP. ii) Name EACH type of neuron. iii) Name the function of neuronQ. g) (i) Name TWO tissues or organs controlled by the autonomic nervous system. ii) Explain the role of the autonomic nervous system in controlling one of the tissues or organs you mentioned in part (i). iii) State ONE difference between the peripheral nervous system and the autonomic nervous system.
Classification and the Species Concept
How many species of snake are there in the area shown in the diagram. ii) Suggest a mechanism that could lead to a change in the number of snake species in this habitat. iii) Discuss TWO other mechanisms that can lead to the formation of new species.
Use examples from these orders in your answers to the following questions. i) Name FOUR characteristics you would use to justify classifying an organism as an insect. ii) Describe TWO characteristics you would use to determine whether an insect specimen belonged to one of the orders you studied. iii) Describe TWO common characteristics of insects that you would NOT use to classify this specimen at the order level. e). The plants have many similarities, but are found in different places. i) Describe in detail THREE characteristics of the plants that you will study to determine whether the plants are of the same species. ii) What additional information do you need to determine whether these plants may belong to the same species.
The plants have many similarities but are found in different locations. i) Describe in detail THREE characteristics of the plants that you would study to determine whether they are of the same species. ii) What additional information do you need to determine whether these plants belong to the same species. f) The diagram shows the number of bird species present in different parts of the slope.
The Human Species
Jones, Martin & Pilbeam, Cambridge Encyclopedia of Human Evolution, 1992, p 402 © Cambridge University Press, Reprinted by permission of Cambridge University Press. Explain how this development was able to affect the growth rate of the human population. ii) Suggest a reason for the rapid increase in human population in the last 200 years. iii). How could improved technology and genetic techniques affect the pattern of human growth over the next 1000 years. ii) Give TWO examples of polymorphism in humans and suggest ONE possible adaptive advantage for each. g) 'Cultural development in humans includes the transmission of learned behaviour.'. i) Justify this statement using TWO cultural examples. ii) Evidence of cultural development is sometimes difficult to find.
Genes in Action
A particular insect chromosome is known to contain four autosomal genes, B, R, H, L. Describe how such genes can be mapped using recombination frequencies for these genes. ii) The Human Genome Project offers many possible benefits to humans, but it also raises some possible ethical questions. Give ONE example of such a benefit and ONE example of an ethical issue raised by the Human Genome Project. Recently, more advanced methods for direct manipulation of DNA base sequencing have become available. i) Distinguish between the techniques of artificial selection and crossing of animals and plants. ii) Describe ONE technique of direct DNA manipulation that can be used to produce benefits for humanity.
Today, a number of techniques exist to directly analyze the DNA base sequence of chromosomes. Recently, more advanced methods for direct manipulation of DNA base sequencing have become available. i) Distinguish between the techniques of artificial selection and crossing of animals and plants. ii) Describe ONE technique of direct DNA manipulation that can be used to produce benefits for humanity. e) The graph shows the egg production figures (by weight) for a poultry farm.
Describe the shape of this curve and the possible genetic processes that determine the weight of the eggs in the poultry. f) The following family tree describes the inheritance of blood groups in a particular family. i).
Predict the genotypes of both parents (individuals (1) and (2)). ii) If individuals (7) and (8) were to have another child, what would be the chance that it would have blood type AB. Using the base sequence in the coding strand of DNA, and the mRNA codon–amino acid table below, predict the amino acid sequence that will be produced by the above gene.
Human Environmental Impact
The three graphs show the growth of the human population over different periods. i) Describe the growth patterns of the human population shown by the graphs. ii) Describe ONE change in human activity that has resulted in the difference between graphs X and Y. iii) State TWO human activities that resulted in the difference between graphs Y and Z. c) Resources can be classified as renewable or non-renewable. i) Give ONE example of a non-renewable energy resource. ii) Describe TWO measures that can be taken to conserve this non-renewable energy resource. iii) Describe ONE renewable alternative to this non-renewable energy resource. iv) Describe TWO problems associated with the renewable energy resource you identified in part (iii).
How would this be determined for a specific species. ii) Name ONE threatened species and describe TWO management strategies that can be used to minimize the current threats to this species. e) Monoculture is an agricultural practice in which extensive areas of land are used to grow a single species (eg pine plantations). i) Describe ONE impact this practice could have on the native species in this area. ii) Some monocultures require intensive irrigation. Explain the long-term adverse effects it has on the environment. f) It has recently been estimated that the grain yield per hectare must double by the year 2020 to feed the expected world population of 7·7 billion. To maintain food supplies, the use of pesticides to combat agricultural pests will have to be increased. i) Describe TWO factors that limit the current use of conventional chemical pesticides. ii) Describe ONE method that can limit, or limit, the impact of pesticides on the environment. g).
BIOLOGY
2 UNIT
PART B ANSWER BOOK
PART C ANSWER BOOK