preliminary biology - sciencepress · pdf fileevolution of australian biota xiii ... evolution...

Kerri Humphreys

PRELIMINARY BIOLOGY

© Science Press 2007First published 2007 Reprinted 2008, 2010

Science PressPrivate Bag 7023 Marrickville NSW 1475 AustraliaTel: (02) 9516 1122 Fax: (02) 9550 [email protected] www.sciencepress.com.au

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of Science Press. ABN 98 000 073 861

Contents

Introduction vVerbs to Watch vi

Dot Points

A Local Ecosystem viiPatterns in Nature ixLife on Earth xiEvolution of Australian Biota xiii

Questions

A Local Ecosystem 1Patterns in Nature 21Life on Earth 55Evolution of Australian Biota 81

Answers

A Local Ecosystem 109Patterns in Nature 117Life on Earth 129Evolution of Australian Biota 137

Dot Point Preliminary Biology iii Contents

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Contents iv Dot Point Preliminary Biology

Science Press

Introduction

What the book includes

syllabus for each topic in the Year 11 Biology course:

Also included are typical experimental results for students to analyse if the third column of the syllabus indicates

Format of the book

The book has been formatted in the following way:

1. Main topic statement (column 1 of syllabus)

1.1etc Syllabus requirement from columns 2 and 3.

1.1.1

1.1.2

worth in an examination. As a rough rule, every two lines of answer might be worth one mark. Note that in

biology involved is worth only one mark.

How to use the book

You may have done work in addition to this with your teacher as extension work. Obviously this is not covered, but you may need to know this additional work for your school exams.

spend more time revising later, and allow you to spend your study time more productively.

Dot Point Preliminary Biology v Introduction

Science Press

account, account for State reasons for, report on, give an account of, narrate a series of events or transactions.

analyse Identify components and the relationships among them, draw out and relate implications.

apply Use, utilise, employ in a particular situation.

appreciate Make a judgement about the value of something.

assess

results or size.

calculate

clarify Make clear or plain.

classify Arrange into classes, groups or categories.

compare Show how things are similar or different.

construct Make, build, put together items or arguments.

contrast Show how things are different or opposite.

critically (analyse/evaluate) Add a degree or level of accuracy, depth, knowledge

deduce Draw conclusions.

demonstrate Show by example.

describe Provide characteristics and features.

discuss Identify issues and provide points for and against.

distinguish Recognise or note/indicate as being distinct or different from, note difference between things.

evaluate Make a judgement based on criteria.

examine

explain Relate cause and effect, make the relationship between things evident, provide why and/or how.

extract Choose relevant and/or appropriate details.

extrapolate Infer from what is known.

identify Recognise and name.

interpret Draw meaning from.

investigate

justify Support an argument or conclusion.

outline Sketch in general terms; indicate the main features.

predict Suggest what may happen based on available data.

propose Put forward (a point of view, idea, argument, suggestion etc) for consideration or action.

recall Present remembered ideas, facts or experiences.

recommend Provide reasons in favour.

recount Retell a series of events.

summarise Express concisely the relevant details.

synthesise Put together various elements to make a whole.

Verbs to Watch

Verbs to Watch vi Dot Point Preliminary Biology

Science Press

Dot Point Page

1. Distribution, diversity and numbers determined by abiotic and biotic factors 21.1 Abiotic characteristics 21.2 Factors determining distribution and abundance 31.3 Photosynthesis and respiration 31.4 Uses of energy 3

1.7 Applied Question Section 1 62. Each ecosystem is unique 72.1 Population trends 7

2.3 Allelopathy, parasitism, mutualism and commensalism 92.4 Role of decomposers 9

Dot Point Page

2.5 Trophic interactions, food chains, webs, pyramids 102.6 Adaptation and problems inferring reason for adaptation 112.7 Examples of adaptations to factors in environment 112.8 Adaptations in local ecosystem 11

of competition 122.10 Human impact 122.11 Investigation: Field study 132.12 Food chains and webs 172.13 Analysis of ecosystem report 172.14 Applied Question Section 2 19Answers to A Local Ecosystem 109

A Local Ecosystem

Dot Point Preliminary Biology vii A Local Ecosystem

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Notes

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A Local Ecosystem viii Dot Point Preliminary Biology

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1. Organisms are made of cells 221.1 Historical development cell theory 221.2 Evidence to support cell theory 231.3 Technological advances and cell theory 231.4 Cell organelles and microscopes 231.5 Organelle structure and function 241.6 Investigation: Technology, the microscope and cell theory 251.7 Investigation: Cells under a light microscope 261.8 Investigation: Micrographs of organelles 271.9 Applied Question Section 1 282. Membranes separate and link cells with the environment 292.1 Major groups of substances in cells 292.2 Movement into and out of cells 292.3 Current model of the cell membrane 302.4 Diffusion and osmosis 302.5 Surface area to volume ratio and rate of reaction 31

2.7 Investigation: Cell membrane model 322.8 Investigation: Difference between osmosis and diffusion 332.9 Investigation: Surface area to volume ratio and rate of diffusion 342.10 Applied Question Section 2 363. Specialised structures to obtain nutrients 373.1 Cells, tissues, organs and systems 373.2 Autotrophs and heterotrophs 373.3 Materials for and role of photosynthesis 37

photosynthesis reaction 383.5 Surface area of structures that obtain water 38

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3.6 Shape and structure of leaves 393.7 Teeth 403.8 Digestive systems of vertebrate herbivore and carnivore 403.9 Investigation: Photosynthesis and light and chlorophyll 413.10 Investigation: Surface area and rate of reaction 423.11 Investigation: Digestive systems of herbivore, carnivore, nectar feeder 433.12 Applied Question Section 3 444. Gas exchange and transport systems 454.1 Role of respiratory, circulatory, excretory systems 45

mammal 45

4.4 Root hairs, xylem, phloem, stomates, lenticels 474.5 Open and closed circulatory systems 484.6 Investigation: Factors affecting rate of transpiration 484.7 Investigation: Movement of materials in xylem or phloem 494.8 Investigation: Technologies, radioisotopes and elements in plants and animals 494.9 Applied Question Section 4 505. Growth and repair 515.1 Mitosis and its role 515.2 Sites of mitosis in plants, insects, mammals 515.3 Cytokinesis 515.4 DNA in mitochondria, nuclei, chloroplasts 525.5 Investigation: Mitosis in cells 525.6 Applied Question Section 5 54Answers to Patterns in Nature 117

Patterns in Nature

Dot Point Preliminary Biology ix Patterns in Nature

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Patterns in Nature x Dot Point Preliminary Biology

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Life on Earth

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1. Rocks provide evidence for origin of life on Earth 561.1 Early Earth and origin of molecules 561.2 Cosmos, organic chemicals and origin of life 561.3 Two theories of origin of organic chemicals 57

experiment and primitive atmosphere 571.5 Changes in technology and increased understanding 581.6 Investigation: Urey and Miller experiment 591.7 Applied Question Section 1 602. The fossil record shows evolution of living things 612.1 Major stages in evolution of living things 612.2 Palaeontological and geological evidence 622.3 Anoxic to oxic atmosphere 63

and different cultures 642.5 Investigation: Timeline for evolution of life 642.6 Investigation: Plant and animal fossils 652.7 Investigation: Increased fossil record and new ideas on history of life 652.8 Applied Question Section 2 66

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3. Further developments and discovery of new organisms increases understanding 673.1 Technology and procaryotes 673.2 Investigation: Environments past and present and procaryotes 673.3 Procaryotes and their role in their environment 693.4 Investigation: Diverse environments and alternatives for origin of life 703.5 Applied Question Section 3 724. Present-day organisms increase understanding of past 734.1 Need to classify 73

4.3 Levels of organisation 74

4.5 Binomial system 764.6 Classifying extinct organisms 76

on Earth 774.8 Investigation: Dichotomous keys 774.9 Applied Question Section 4 79Answers to Life on Earth 129

Dot Point Preliminary Biology xi Life on Earth

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Life on Earth xii Dot Point Preliminary Biology

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Evolution of Australian Biota

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1. Continental drift and Australia 821.1 Australia, Gondwana and plate tectonics 821.2 Evolutionary relationships and megafauna 83

1.4 Investigation: The platypus 841.5 Applied Question Section 1 842. 852.1 Variation in a species 852.2 Variation and survival of species 852.3 Evidence of changing Australian environments 862.4 Australia and temperature variation 862.5 Change from rainforest to grassland 862.6 Current theories for change 872.7 Darwin and Australian biota 872.8 Investigation: Timeline for formation of Australia 882.9 Investigation: Australian fossils and evolution of species 892.10 Investigation: Australian fossils and current life forms 90

2.12 Investigation: Variation in two living species 912.13 Applied Question Section 2 923. Reproductive adaptations of Australian plants and animals 933.1 Meiosis and mitosis 93

Dot Point Page

3.2 Investigation: Tabulate differences between mitosis and meiosis 933.3 External and internal fertilisation 943.4 Fertilisation and colonisation of water and land 953.5 Pollination, seed dispersal and asexual reproduction 953.6 Mechanisms for fertilisation and survival of embryo 973.7 Reproductive adaptations and continuity of species 983.8 Asexual reproduction advantages 993.9 Investigation: Internal and external fertilisation and colonisation of land 1003.10 Investigation: Pollination and native

3.11 Applied Question Section 3 1024. Palaeontology and past environments increase understanding of possible future 1034.1 Human impact 1034.2 Palaeontology and species distribution 1034.3 Maintaining biodiversity 1044.4 Investigation: Reason for evolution, survival, extinction 1044.5 Investigation: Monitoring biodiversity 1054.6 Applied Question Section 4 106Answers to Evolution of Australian Biota 137

Dot Point Preliminary Biology xiii Evolution of Australian Biota

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Evolution of Australian Biota xiv Dot Point Preliminary Biology

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Dot Point Preliminary Biology 1 A Local Ecosystem

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DOT POINTA Local Ecosystem

A Local Ecosystem 2 Dot Point Preliminary Biology

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1. The distribution, diversity and numbers of plants and animals in ecosystems are determined by biotic and abiotic factors.

1.1 Compare the abiotic characteristics of aquatic and terrestrial environments.

1.1.1 List abiotic factors that affect the distribution, diversity and numbers of plants and animals in ecosystems.

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1.1.2 environments – availability of oxygen, temperature variation, pressure variation, viscosity, light penetration, buoyancy and availability of ions.

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1.2 Identify the factors determining the distribution and abundance of a species in each environment.

1.2.1 Identify factors which determine the distribution and abundance of a species in either a

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1.3 Describe the roles of photosynthesis and respiration in ecosystems.

1.3.1 Distinguish between photosynthesis and respiration.

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1.3.2 Discuss the roles of photosynthesis and respiration in ecosystems.

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1.4 Identify uses of energy by organisms.

1.4.1 Describe THREE uses of energy by organisms.

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1.5 Identify the general equation for aerobic cellular respiration and outline this as a summary of a chain of biochemical reactions.

1.5.1

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1.5.2 Summarise the chemical reaction of aerobic cellular respiration.

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1.6 Process and analyse information obtained from a variety of sampling studies to justify the use of different techniques to make population estimates when total counts cannot be performed.

1.6.1spheres. Thirty of these spheres had been coloured red with a highlighter pen. The bag was shaken by the students and then twenty spheres were taken out, without looking. The number coloured red was recorded and the twenty spheres were returned to the bag. The removal of twenty spheres and recording of the number coloured red was repeated until they had ten trials.

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(b) What was the purpose of colouring thirty spheres red with a highlighter pen?

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Estimated population size =

number tagged × number in recapturenumber of tagged in recapture

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1.6.2is used when a total count cannot be performed.

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1.7 Applied Question Section 1

The minke whale is the smallest baleen whale with two blowholes and a characteristic white band on

Oceans. In the Southern Hemisphere they have a circumpolar distribution between Antarctica and Madagascar.

Population sizes are much debated and concern for minke whales led to their protection by the

size and distribution of minke whales. Methods used included a sighting survey, direct data

Describe the factors that determine the distribution and abundance of minke whales and how

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2. Each local aquatic or terrestrial ecosystem is unique.

2.1 Examine trends in population estimates for some plant and animal species within an ecosystem.

2.1.1 Outline why population numbers for plants and animals do not stay constant over time.

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2.1.2 The Endangered Species Protection Act 1992 listed over 1100 native species as either

the Canberra spider orchid is listed as a nationally endangered plant. Identify contributing factors that are causing this trend in declining numbers of native species.

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2.2 Outline factors that affect numbers in predator and prey populations in the area studied.

2.2.1

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2.2.2the population sizes.

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2.2.3 A group of Biology students studied the numbers of aphids and ladybird beetles on rose bushes in the ornamental garden of their school. Ladybird beetles eat aphids.

Ladybird beetle Rose aphid Aphids on a rose

The students collated their results and drew the following graph to summarise their data.

Time (t)

Pop

ulat

ion

size

prey

predator

Discuss the factors which lead to the shape of this graph and why there is this variation in the population size of aphids and ladybird beetles in the garden. Identify which curve is the aphid and which is the ladybird beetle.

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2.3 Identify examples of allelopathy, parasitism, mutualism and commensalism in an ecosystem and the role of organisms in each type of relationship.

2.3.1of the named relationships.

Relationship Definition ExampleRoles of organisms in

relationship

Allelopathy

Parasitism

Mutualism

Commensalism

2.4 Describe the role of decomposers in ecosystems.

2.4.1 Name two groups of organisms which are decomposers and explain why they are important in maintaining the balance in an ecosystem.

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2.5 Explain trophic interactions between organisms in an ecosystem using food chains, food webs and pyramids of biomass and energy.

2.5.1 Trophic interactions show feeding relationships in food chains and food webs. Draw a food web including a third order consumer and at least one organism that occupies more than one trophic level. Then complete the table to identify the trophic level of each organism.

Food Web

Organism Trophic level Organism Trophic level

2.5.2 The energy pyramid below shows 100 000 joules of energy in a plant in an ecosystem. On the diagram identify the different trophic levels and the amount of energy passed to each level. Explain how energy moves through an ecosystem.

100 000 joules of energy in producer

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organisms as adaptations for living in a particular habitat.

2.6.1

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2.6.2adaptation for living in a particular habitat.

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2.7 Identify some adaptations of living things to factors in their environment.

2.7.1 Complete the following table to classify an adaptation as either physiological, structural or behavioural and the feature of the environment which this adaptation addresses.

Adaptation Type of adaptation Feature of environment

Layer of blubber in a whale

Leaves in the shade are larger and a darker green

Whales emit very low frequency sounds

Lizards sunbake on rocks in the sun at sunset

Goldfish release copious amounts of dilute urine

Rate of photosynthesis increases in grass in spring

2.8 Identify and describe in detail adaptations of a plant and an animal from the local ecosystem.

2.8.1 Name an ecosystem and for this ecosystem detail three adaptations of an animal and three adaptations of a plant from that ecosystem.

Name of ecosystem: .................................................................................................................................................................................

Feature Plant Animal

Name of organism

Adaptation 1

Adaptation 2

Adaptation 3


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2.9 Describe and explain the short-term and long-term consequences on the ecosystem of species competing for resources.

2.9.1an ecosystem.

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2.10 Identify the impact of humans in the ecosystem studied.

2.10.1named ecosystem.

Human activity How activity impacts on named ecosystem

Name of ecosystem

Land clearing

Burning fossil fuels

Introduced species

Use of fertilisers leading to eutrophication

Salination of waterways


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ecosystem to identify data sources and: measure abiotic variables, estimate population size and distribution, describe trophic interactions, tabulate data, graph data and evaluate variability in measurements.

Complete the following table to summarise the instruments used to measure abiotic variables.

Instrument Diagram of instrument Abiotic feature it measures

Thermometer

Aneroid barometer

Anemometer

pH meter

Luxmeter

Wet and dry bulb hygrometer

Dissolved oxygen content kit


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2.11.2show your results.

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2.11.3 Describe how you estimated the size of a plant population.

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2.11.4 Describe how you estimated the size of an animal population.

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2.11.5to show your results.

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2.11.6 Describe three trophic interactions between organisms you could observe in a named ecosystem.

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2.11.7 For one of your examples in estimating either distribution or abundance, evaluate variability

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2.11.8a checklist you need to follow to make sure your graph is correct and contains all necessary components.

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2.11.9 Draw a graph for the following data which shows changes in temperature in Sydney in 2005.

DateTemperature (°C)

DateTemperature (°C)

Maximum Minimum Maximum Minimum

Sun 13 Feb 05 27.8 19.4 Fri 18 Feb 05 27.6 19.2

Mon 14 Feb 05 26.2 16.6 Sat 19 Feb 05 28.4 21.4

Tues 15 Feb 05 32.3 19.0 Sun 20 Feb 05 26.1 20.5

Wed 16 Feb 05 25.3 21.2 Mon 21 Feb 05 28.5 21.0

Thurs 17 Feb 05 24.0 19.7 Tues 22 Feb 05 27.7 19.1


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webs to illustrate the relationships between member species in an ecosystem.

2.12.1 Study the following food web from an open woodland.Owl Quoll

Wedgetail eagle

Tick

Wallaby

Grasses

Feather-tail glider

Banksia nectar

Ringtail possum

Blue-tongue lizard

Echidna

Termite Leaf-eating beetle

Magpie

Flowers/leaves/wood eucalypt

relationship.

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2.13 Process and analyse information and present a report of the investigation of an ecosystem in which the purpose is introduced, the methods described and the results shown graphically, and use available evidence to discuss their relevance.

2.13.1ecosystem, including a graph in the results.

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The following notes were made by a Preliminary Biology student as he collected data about the local dry sclerophyll forest.

trees which had stick insects eating the leaves. A parasitic mistletoe was in the acacia and a mistletoe bird was eating the mistletoe. The gully also had a lilli pilli tree and possums and magpies were seen eating the lilli pilli berries. The possum moved to the acacia and ate the fruit from the mistletoe. A kookaburra ate the lone moth and then ate one of the stick insects. Another kookaburra ate a mistletoe bird chick.

(a) Construct a food web to show the trophic relationships observed by the Biology student.

(b) Identify a major group of organisms which is not indicated in this food web and discuss why this group plays an important role in the ecosystem.

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(c) Name the highest order consumer in this food web and then draw a food chain to show this trophic level.

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(d) If humans removed the grevillea plants, describe how this would impact on other populations in the short term and long term.

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Notes

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Dot Point Preliminary Biology 107 Answers

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DOT POINTAnswers

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Answers 108 Dot Point Preliminary Biology

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A Local Ecosystem

1.1.1length, humidity, pH of soil or water, availability of ions in soil or water, salinity in soil or water, buoyancy, viscosity, pressure, landforms, soil type and porosity of soil.

1.1.2

Abiotic characteristic Aquatic environment Terrestrial environment

Availability of oxygen – oxygen is needed for aerobic respiration

Oxygen is less available in water than in air. Warm water holds less oxygen than cold water. There is less oxygen available at greater depths.

Oxygen is readily available in air making up approximately 20% of atmosphere. Diffusion is faster in air than in water.

Temperature variation

Temperature variation depends on depth of water and latitude. Very large bodies of water, e.g. oceans have relatively small variation in temperature, small bodies of water, e.g. small ponds may heat up and cool more quickly.

Temperature variation depends on latitude and altitude. Very large variations can occur in some areas, e.g. inland desert with hot day and cold night, while less variations occur in tropical, seaside locations. Variations can be greater than aquatic environments.

Pressure variation Water pressure increases with the depth of the water. Air pressure decreases with altitude.

ViscosityWater is more viscous than air causing a higher resistance for the movement of organisms through the medium.

Air is less viscous than water offering less resistance for the movement of organisms through the medium.

Light penetration

Light penetration depends on depth. Little light penetrates below 100 metres. Light penetration also depends on turbidity, pollutants, suspended particle content and abundance of organisms such as algae.

Light is easily available. The amount of light can be limited by other vegetation or topographic features.

Buoyancy Water provides more support for organisms than air. Air provides less support for organisms than water.

Availability of ionsIons are readily available in salt water but less available in fresh water. Higher temperatures decrease solubility of ions.

Ions are available in the soil but not in air.

1.2.1 The abundance of a species refers to the numbers of individuals in an area while the distribution of a species refers to the

abundance and distribution of a species. Factors include the availability of the food source, the abundance and range of predators, competitors for food sources or resources, climate conditions such as temperature and rainfall, chemical conditions such as pH or availability of gases and ions, or prevalence of parasites and disease.

1.3.1compounds using light energy; while respiration is a series of chemical reactions which releases energy from complex carbohydrates.

1.3.2 Photosynthesis uses carbon dioxide and water to produce glucose and oxygen gas. The main roles of photosynthesis in ecosystems is related to each product – the formation of glucose enables the conversion of radiant energy into chemical energy to provide a form of energy to sustain life in the food chain and the production of oxygen gas provides a basic material for aerobic respiration. The main role of respiration in ecosystems is to use stored chemical energy to produce the energy needed

the existence of multicellular life forms on Earth. The roles of photosynthesis and respiration are vitally important for the existence of the current complex life forms on Earth.

1.4.1 Energy released by respiration can be used in many different ways depending on the needs of the organism. Endotherms, such as mammals and birds use the heat released by respiration as a means of maintaining body temperature. Energy from respiration can also be used in synthesis chemical reactions, e.g. the synthesis of polysaccharides from simple sugars. Energy can also be used for the active transport of materials across cell membranes, e.g. accumulation of inorganic ions against a concentration gradient.

1.5.1

1.5.2products, however, the process does not occur in one step. There are about 50 different stages, each catalysed by a different enzyme.

1.6.1


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(c) Estimated population size =number tagged × number in recapture

number of tagged in recapture Number tagged = 30 Number in recapture = 20 Number of tagged in recapture = 3.2

Estimated population size = 30 20×3 7.

= 162.16 = 162 spheres in population

1.6.2are investigating. If the organism is found over a wide area or if the numbers are too great to count individuals scientists use

the greater the statistical accuracy of the results. Quadrats can also be placed along a transect of the area to show how distribution and abundance changes across the area. Quadrats are useful for estimating vegetation abundance or for studying

an animal is caught, tagged and then released to wander freely and mix with the rest of the population. At a later date another group is caught and the number of tagged individuals can be used in the formula below to estimate the abundance of that animal in the area.

Abundance = Number tagged in first capture Number caught in second caaptureNumber of tagged in second capture

×

Thus, there are several methods which can be used to estimate abundance and the method used depends on the species involved, e.g. mobile or immobile.


The distribution and abundance of minke whales is determined by such factors as food supply, e.g. location and numbers of

whale is over 2.4 km distant, and adaptive line sampling and sighting surveys depend on weather conditions. Poor conditions can give less accurate estimates. Thus there are several factors that contribute to minke whale abundance and data can only give estimates of abundance.

2.1.1

competitive species, predation, disease or the activities of humans, while other populations may be increasing in number, e.g. due to increase in food, resources or activities of humans.

2.1.2 The trend of declining numbers of native species is due to a variety of factors and each species has particular problems threatening its survival. Competition and land degradation caused by introduced animals, e.g. rabbits and goats is a major factor for many native species. Land clearance for farms and towns has removed the habitat for many species and predation by feral cats and foxes have also had a large impact on the numbers of native species.

2.2.1 A predator eats the prey.

2.2.2 The kookaburra preys on rodents such as the marsupial mouse in woodland ecosystems. The size of the populations of each depends on the size of the ecosystem in which they live. There are usually more mice than kookaburras. Seasonal changes in

differences in numbers.


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2.2.3

beetles which increase in numbers. Note that the crest of the predator curve is after the crest of the prey curve. As the beetles eat the aphids, the number of aphids decreases. This means the number of beetles will fall as their food source is depleted.

predators and the predator curves follows the prey curve with crests and troughs.

2.3.1

Relationship Definition Example Roles of organisms in relationship

AllelopathyRelease of chemical substances by one species to inhibit the growth of another.

Penicillin mouldPenicillin produces a chemical that prevents bacterial growth.

ParasitismOne species benefits and the other species is harmed.

Tick and humanHuman is host and is harmed; tick is the parasite.

Mutualism Both partners benefit. LichenCyanobacteria photosynthesises and provides food; fungi protects and allows survival in dry area.

CommensalismOne species benefits and the other is neither harmed or receives any benefit.

Shark and remora fish

Remora attaches to shark and eats remains of shark’s food and parasites on shark and uses less energy to move around; shark may benefit if parasites are removed.

2.4.1 The two main groups of organisms which are decomposers are fungi and bacteria. Decomposers cause decay and are very important in the cycling of nutrients returning materials to the soil so they can be used again.

2.5.1 Food web:Leaves aphid willy-wagtail feral cat feral fox

ladybird beetle eagle

Organism Trophic level Organism Trophic level

Leaves producer Eagle 3rd order consumer

Aphid 1st order consumer Feral fox 4th order consumer

Willy-wagtail 2nd and 3rd order consumer Ladybird beetle 2nd order consumer

Feral cat 3rd order consumer

2.5.2

Producer 100 000 J

1st order consumer 10 000 J

2nd order consumer 1000 J

3rd order consumer 100 J

Only 10% of energy moves to the next trophic level. The rest of the energy is used at each step for life processes and is eventually lost as heat to the atmosphere.

2.6.1 An adaptation is any feature or characteristic which helps the organism survive in its environment.

2.6.2 Sometimes features are interpreted as adaptations for a particular environment but further investigation shows problems with these inferences. For example, fossils show that 3.5 million years ago humans became upright, with the change in posture causing a changed positioning of the head and neck. This in turn caused a new position of the tongue, throat and vocal cords enabling speech. Thus early inferences on the reason for the evolution of speech needed to be revised.


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2.7.1

Adaptation Type of adaptation Feature of environment

Layer of blubber in a whale Structural Heat is easily lost by conduction in water

Leaves in the shade are larger and a darker green Structural Light intensity is lower in the shade

Whales emit very low frequency sounds Behavioural Very low frequency sounds travel a long way under water

Lizards sunbake on rocks in the sun at sunset Behavioural Temperatures on land can drop rapidly at night

Goldfish release copious amounts of dilute urine Physiological In fresh water osmosis causes water to enter organisms

Rate of photosynthesis increases in grass in spring Physiological Light intensity and water availability increase in spring

2.8.1 Name of ecosystem – rainforest.

Feature Plant Animal

Organism Cymbidium orchid Musky rat-kangaroo

Adaptation 1

Extensive root system – as an epiphyte they need to collect as much water as possible

First toe on hind leg allows climbing on branches and fallen logs

Adaptation 2

Third petal developed into labellum and points down to act as a landing place for a pollinating insect

Diurnal – at first light it begins to search for seeds, fruit, fleshy flowers easier to see in daylight

Adaptation 3

Style and stigma joined together with sticky pollen so the column deposits the pollen on the back of the pollinating insect

Seasonal breeders in response to food supplies

2.9.1 Competition for resources can lead to changes in an ecosystem. The introduction of many species into Australia has led to

of native species, for example, the introduction of rabbits.

2.10.1

Human activity How activity impacts on named ecosystem

Name of ecosystem Dry sclerophyll forest.

Land clearing Many habitats are destroyed to provide land for farms, roads and towns. Cleared land is more susceptible to erosion and land degradation.

Burning fossil fuels Many air pollutants are produced by burning fossil fuels, e.g. carbon monoxide, ash, soot and increased carbon dioxide levels. The higher carbon dioxide levels in turn contribute to the greenhouse effect and global warming.

Introduced species Many species have been introduced into Australia leading to the extinction and endangering of many native species, e.g. rabbits, goats, compete with many native herbivores, and cats, foxes prey on native animals.

Use of fertilisers leading to eutrophication

Soil infertility has meant fertilisers, e.g. nitrates and phosphates are used on farms and these fertilisers leach into the waterways causing a buildup of excess nutrients. Excessive sewage also increases nutrient levels leading to an algal bloom as the algae thrive in the nutrient-rich water. During the night the algae and bacteria decomposers deplete the oxygen levels eventually causing the lake or body of water to become ‘dead’ as fish and other life cannot survive at such low oxygen levels.

Salination of waterways Increased irrigation and the removal of native plants has caused a rise in watertables which in turn has brought salts closer to the surface. The salt kills crops or forms a salt flat and continued salination could mean water will become unsuitable for either irrigation or drinking.


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2.11.1

Instrument Diagram of instrument Abiotic feature it measures

Thermometer Measures temperature in degrees Celsius

Aneroid barometer Measures air pressure in hpa

Anemometer Measures wind speed in km/h

pH meter Measures pH of water or soil on a scale of: 1 (acidic) to 14 (basic)

Luxmeter Measures light intensity in lux

Wet and dry bulb hygrometer Measures temperature of wet and dry bulbs and the temperature difference allows humidity to be read from the table as a percentage

Dissolved oxygen content kit Following instructions of the kit measures dissolved oxygen content in mg/L

2.11.2 To estimate the distribution of the rose population in the school front garden we used a metre ruler and a 30 metre tape measure to measure the ornamental school rose garden and front lawn and then recorded the location of the different plant populations. The following distribution map shows roses at the end of the science block, on the sides of the steps to the administration block and in the central circular garden in the lawn.

N

End of science blockWalkway

Walkw

ayW

alkway

Walkway

WalkwayWalkway

Adm

inistration block

Steps

Rose garden

Grass/weed lawn

2 metres

2.11.3 The school lawn in front of the administration block is mainly common couch grass, with some white clover weeds. The couch grass is matted and it is hard to count individuals, however the clover is kept under control by the gardeners applying weed killers and individuals can be easily counted. To estimate the size of the white clover population we used 20 random

×2. Knowing the total area of the lawn we then estimated the total

number of clover plants in the lawn.


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Common couch grass White clover

2.11.4

was calculated. The number of roses in the garden was counted and then the total number of aphids in the whole area was estimated.

2.11.5 To estimate the distribution of the aphid poluation in the school front garden we used a metre ruler and a 30 metre tape measure to measure the ornamental school rose garden and front lawn and then recorded the location of any observed aphid. The following distribution map shows aphids were found on the roses which are in beds at the end of the science block, on the sides of the steps to the administration block and in the central circular garden in the lawn.

N

End of science blockWalkway

Walkw

ayW

alkway

Walkway

WalkwayWalkway

Adm

inistration block

Steps

Rose garden

Grass/weed lawn

2 metres

2.11.6tongue lizard, and an echidna eating termites.

2.11.7 When estimating the number of aphids in the garden there were several aspects of the method which could lead to variability

suitable. Measurements should be made over a period of time to detect cyclic trends. Sometimes anomalies occur in data.

2.11.8 Checklist for drawing a graph:

(a) Does it have a title? (b) Is the x (c) Is the y (d) Does the scale for the x (e) Does the scale for the y (f) Does the x (g) Does the y

(i) For a line graph, are the points joined by a single line drawn in pencil?


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2.11.9

34

32

30

28

26

24

22

20

18

16

14

13 14 15 16 17 18 19 20 21 22

Date (February 2005)

Tem

pera

ture

(°C

)

Maximum temperature

Minimum temperature

Graph of maximum and minimum temperature for Sydney in 2005

24

2.12.1

2.13.1 Ecosystem report:

Aim:

Risk assessment:

to protect your feet from cuts and abrasions from shells and rocks. Wear a hat and put blockout suncreen on exposed areas such as face, arms and legs to reduce sunburn to skin.

Method: A 30 m tape measure was used to measure the length and breadth of the barnacle zone and the total area of the

2. The total number of each of these four species was then estimated for the barnacle zone. The results were graphed to compare the abundance of the four species in the barnacle zone. Data was analysed and conclusions drawn.

Results Length barnacle zone = 9.6 metres Breadth barnacle zone = 22.4 metres Total area barnacle zone = 215.04 m2

Results Blue periwinkle Pink barnacle Morula Honeycomb barnacle

Quadrat 1 1 4 0 2

Quadrat 2 0 1 0 5

Quadrat 3 2 2 0 3

Quadrat 4 0 3 1 1

Quadrat 5 0 2 1 0

Quadrat 6 1 3 0 6

Quadrat 7 0 2 0 4

Quadrat 8 0 1 0 2

Quadrat 9 0 5 0 3

Quadrat 10 1 1 0 3

Total 5 24 2 29

Density (number/quadrat) 0.5 2.4 0.2 2.9

Density (number/m2) 1.25 × 103 6 × 103 5 × 102 7.25 × 103

Estimated abundance in total area 2.7 × 105 1.3 × 106 1.1 × 105 1.6 × 106


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Species abundance in zone

2.7

13

1.1

16

0

5

10

15

20

Blueperiwinkle

Pinkbarnacle

Morula Honeycombbarnacle

Species

Abu

ndan

ce (

x100

000

) Discussion:

barnacle zone and fewer numbers of blue periwinkles and Morula

and away from wave action. However, the periwinkle feeds on algae and will move to the upper littoral zone to feed. Thus some periwinkles are found in the upper littoral zone. Morulaand moves around to feed on oysters and shelled animals. Thus some are found in the upper littoral zone. The domination of

Conclusion: Two species of barnacles – the pink barnacle and honeycomb barnacle have a greater abundance than Morula and the blue periwinkle in the upper littoral zone.


(a) Food web:Kookaburra

Bee Moth Honeyeater

Grevilleapollen

Stickinsect

Mistletoe bird

Possum

Magpie

Lilly pillyAcacia

Mistletoe

(b) Decomposers, e.g. bacteria and fungi are a major group not mentioned in the food web. Decomposers play a major role in recycling nutrients in the ecosystem. They break down bodies and other organic matter in decay.

(c) Highest order consumer is the kookaburra and it is both a 2nd order consumer and a 3rd order consumer in this food

(d) The removal of the Grevillea plants from the food web will cause a decrease in the bee population and a decrease in the honeyeater population in the short term as their food source has been removed. If they have no other food source they will become extinct in this area in the long term.


preliminary biology - sciencepress · pdf fileevolution of australian biota xiii ... evolution...

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