HIGHER LEVEL IB BIOLOGY YEAR 2: SYLLABUS 2016 – 2017DR PRICE

Email: Jill.Sawyer-price@tasis.chhttps://tasisibbio2015.wordpress.com

TEXTS Oxford IB Diploma 2014 Course Companion (Mindorff and Allott, 2014, Print,

online and Kerboodle) Prentice Hall IB Biology 2012 OSC IB Revision TEXTS

CLASS BLOG: https://tasisibbio2015.wordpress.com (YEAR 1 MATERIAL)

https://tasisbiology.wordpress.com (YEAR 2 MATERIAL)

ESSENTIAL MATERIALS: Biology course notesIdeally, two thick notebooks for each term – one for classwork , and one for submitted homework (so that you don’t lose all of your valuable homework assignments!)…

CONTENTThe 2016 IB Biology syllabus is accessible on the class Blog. Printed syllabi for each topic will be distributed as we proceed through the course.

OFFICE HOURS: By appointment only. I am VERY approachable and ready to help! The best way to set up a time for extra help is by email. Contact me at Jill.Sawyer-price@tasis.ch

IB Grade level boundaries (HL):1: 0 – 15%2: 16 – 29%3: 30 – 42%4: 43 – 54%5: 55 – 68%6: 67 – 78%

7: 79%+

TASIS SEMESTER GRADE: COURSEWORK: 75% FINAL EXAM: 25%

YEAR GRADE: 1ST SEMESTER: 50% 2ND SEMESTER: 50%

COURSEWORK Homework 25% Tests/Projects 30% Lab work 20%

INTEGRITYOn May 1st 2017, there will only be you and the IB examination board to

grade your knowledge

Be honest with yourself, your classmates and your teacher.

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Don't take credit for work that isn't yours and ask for help when you need it.

Attendance: You are expected to arrive on time and to be in your seat with your homework and your notebook on your desk. Attendance will be recorded within the first 3 minutes of the scheduled class period.A pattern of tardiness will be regarded as not meeting the expectations of the class and will affect your effort grade.

MOBILE PHONESWITHOUT EXCEPTION, mobile phones should not be used in class. Once class has begun, WITHOUT EXCEPTION, any mobile phone visible in class will be confiscated and kept for 24 h. If mobile phones begin to disrupt the classroom, then the whole class will be required to deposit their phones at the beginning of each class and collect them at the end.

Homework: Homework will be assigned frequently and is often incorporated into the following day’s class. A late assignment defeats the purpose of completing it. Therefore, LATE HOMEWORK WILL NOT BE ACCEPTED AND WILL BE GRADED AS A ZERO. Assignments include, but are not limited to: worksheets; problem sets; readings; preparing for a discussion/presentation etc. Late projects (larger assignments) will be accepted up to three calendar days after the due date. However, each day that the project is late, 10% of the grade will be lost. After the third day the project will no longer be accepted.

Make-up Work: You are responsible for obtaining missed assignments. If you know in advance you will be missing class for co-curricular commitments such as a pre-arranged appointment, you should notify me at least 2 days in advance.

CLASS TEST DATES (may be subject to minor alteration)

Tests and quizzes will generally take place on FRIDAYS and MONDAYS.

IA SUBMISSION: Jan 27, 2017EXAM: MAY 1 (Paper 1 and 2, Monday) and 2 (Paper 3): 31 weeks from

beginning of term

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FALL TERM SCHEDULE

Date

Week/

UNIT

TOPIC IB Prescribed Practical Work

Unit 1 : Cellular Respiration (6 h)Sept 5

1 2.8/ 8.2 (HL): Respiration Setting up sealed mesocosms to evaluate sustainability.(IB prescribed Practical 5)

Practical 1: Investigations using respirometers

Sept 12

1 2.8/ 8.2 (HL): Respiration

Sept 19 UNIT 1 TEST (Topics 2.8/8.2)

Unit 2: Photosynthesis

Sept 19

3/3 2.9/8.3: Photosynthesis Setting up sealed mesocosms to evaluate sustainability. (IB prescribed Practical 5)Practical 2: Separation of photosynthetic pigments by chromatograph (IB prescribed Practical 4)

Sept 26

4/4 2.9/8.3: Photosynthesis

Oct 3

5/4 2.9/8.3: Photosynthesis

October 6th

Unit 2 test (Topics 2.8/8.3)

Unit 3: Plant ScienceOct 10

6/5 9.1 Xylem Transport Setting up sealed mesocosms to evaluate sustainability. (IB prescribed Practical 5)

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Measurement of transpiration rates using photometers (IB prescribed Practical 6)

Oct 17

7/5 9.2 Phloem Transport

Oct 24

8/5 9.3 Plant Growth

Nov 1 - 4 ACADEMIC TRAVELNov

79/5 9.4 Plant reproduction

Nov 11 Test on Plant ScienceUnit 4: Ecology

Nov 14

10/6 4.1: Community Ecology Setting up sealed mesocosms to evaluate sustainability. (IB prescribed Practical 5)

Nov 21

11/6 4.2: Energy Flow4.3: Carbon cycling

Nov 28

12/6 4.4: Climate change

Dec 5 Test on Topic 4 EcologyUnit 5: Physiology 1

Dec 5

14 Digestion and absorption (6.1/ D2)

Dec 12

15 Completion of IA practical work/ Review of Nutrition and health

Test on Topics D1/D2/6.1MERRY CHRISTMAS!

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UNIT 1: CELLULAR RESPIRATION (ANAEROBIC) Estimate of timing:  3 daysIB topic(s):  2.8 and 8.2

Essential Idea(s):  Cell respiration supplies energy for the functions of life

Lesson

Topic Days

Statement(s) and Objective(s) Skills/ Activities

1 Introduction to Respiration

1 2.8.U1:  Cell respiration is the controlled release of energy from organic compounds to produce ATP (details of metabolic pathways are not needed; substrates and final waste products should be shown

8.2.U1:  Cell respiration involves the oxidation and reduction of electron carriers

2.8.U3:  Anaerobic cell respiration gives a small yield of ATP from glucose

2 Glycolysis 1 8.2.U3:  In glycolysis, glucose is converted to pyruvate in the cytoplasm (names of intermediate compounds not required)

8.2.U2:  Phosphorylation of molecules makes them less stable

8.2.U4:  Glycolysis gives a small net gain of ATP without the use of oxygen

2.8.U2:  ATP from cell respiration is immediately available as a source of energy in the cell

3 Anaerobic respiration

2 2.8.A1:  Use of anaerobic cell respiration in yeasts to produce ethanol and carbon dioxide in baking

2.8.A2:   Lactate production in humans when anaerobic respiration is used to maximize the power of muscle contractions

  

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UNIT 1: CELLULAR RESPIRATION (AEROBIC) Estimate of timing:  3 daysIB topic(s):  2.8 and 8.2Essential Idea(s):  Energy is converted to a usable form in cell respiration

Lesson

Topic Days

Statement(s) and Objective(s)

Skills/ Activities

1 Overview 3 2.8.U4:  Aerobic cell respiration requires oxygen and gives a large yield of ATP from glucose

2.8.NOS:  Assessing the ethics of scientific research- the use of invertebrates in respirometers experiments

8.2.S1:  Analysis of diagrams of the pathways of aerobic respiration to decide where  decarboxylation and oxidation reactions occur

2.8.S1:  Analysis of results from experiments involving measurement of respiration rates in germinating seeds or invertebrates using a respirometer (students should know that an alkali is used to absorb CO2 so reductions in volume are due to O2 use.  Temperature should be controlled to avoid volume changes due to temperature fluctuations.

2 Mitochondria

1 8.2.U12:  The structure of the mitochondrion is adapted to the function it performs

8.2.A1:  Electron tomography used to produce images of active mitochondria

8.2.S2:  Annotations of a diagram of mitochondrion to indicate the adaptations to its function

3 Linking Reaction

0.5 8.2.U5:  In aerobic cell respiration pyruvate is decarboxylated and oxidized

8.2.U6:  In the link reaction pyruvate is converted into acetyl coenzyme A

4 Kreb’s Cycle

0.5 8.2.U7:  In the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon

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dioxide (names of intermediate compounds are not required)

5 Electron Transport Chain

1 8.2.U8:  Energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD

8.2.U9:  Transfer of the electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping

8.2.U11:  Oxygen is needed to bind with the free protons to maintain the hydrogen gradient, resulting in the formation of water

6 Chemiosmosis

1 8.2.U10:  In chemiosmosis protons diffuse through ATP synthase to generate ATP

8.2.NOS:  Paradigm shift-chemiosmotic theory led to a paradigm shift in the field of bioenergetics

TOK:  Peter Mitchell’s chemiosmotic theory encountered years of opposition before it was finally accepted.  For what reasons does falsification not always result in an immediate acceptance of new theories or a paradigm shift?

  

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UNIT 2: PHOTOSYNTHESIS (I): Light and Pigments           IB topic(s):  2.9Essential Idea(s):  Specific wavelengths of light activate photosynthetic pigments.

Lesson

Topic Days

Statement(s) and Objective(s)

Activities

1 Intro to photosynthesis

1 2.9.U1:  Photosynthesis is the production of carbon compounds in cells using light energy

2.9.U5:  Energy is needed to produce carbohydrates and other carbon compounds from carbon dioxide

2 Pigments and Chromatography

2 2.9.U3:  Chlorophyll absorbs red and blue light most effectively and reflects green light more than other colours

2.9.S2:  Separation of photosynthetic pigments by chromatograph (Practical 4)

3 Wavelengths of Light

1 2.9.U2:  Visible light has a range of wavelengths with violet the shortest wavelength and red the longest (400-700 nm = visible light.  Don’t need to know specific wavelength for each color)

2.9.S3:  Drawing an absorption spectrum for chlorophyll and an action spectrum for photosynthesis

 

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UNIT 2:  PHOTOSYNTHESIS (II)  IB topic(s):  2.9 and 8.3      Essential Idea(s):   Photosynthesis uses the energy in sunlight to

produce the chemical energy needed for life / Light energy is converted into chemical energy

Lesson

Topic Days

Statement(s) and Objective(s)

Activities

1 Chloroplast structure

8.3.U14:  The structure of the chloroplast is adapted to its function in photosynthesis

8.3.S1:  Annotation of a diagram to indicate the adaptations of a chloroplast to its function

2 Light Dependent reactions

8.3.U1:  Light-dependent reactions take place in the intermembrane space of the thylakoids

8.3.U4:  Absorption of light by photosystems generates excited electrons

8.3.U6:  Transfer of excited electrons occurs between carriers in thylakoid membranes

8.3.U7:  Excited electrons from Photosystem II are used to contribute to generate a proton gradient

8.3.U8:  ATP synthase in thylakoids generates ATP using the proton gradient

8.3.U9:  Excited electrons from Photosystem I are used to reduce NADP

8.3.U2:  Reduced NADP and ATP are produced in the light-dependent reactions

2.9.U4:  Oxygen is produced in photosynthesis from the photolysis of water

2.9.A1:  Changes to the

Aim 6:  Hill’s method of demonstrating electron transfer in chloroplasts by observing DCPIP reductions

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Earth’s atmosphere, oceans and rock deposition due to photosynthesis

8.3.U5:  Photolysis of water generates electrons for use in the light-independent reactions

3 Light Independent reactions

8.3.U3:  Light –independent reactions take place in the stroma

8.3.U10:  In the light-independent reaction a carboxylase catalyses the carboxylation of ribulose-bisphosphate

8.3.U11:  Glycerate 3-phosphate is reduced to triose phosphate using a reduced NADP and ATP

8.3.U12:  Triose phosphate is used to regenerate RuBP and produce carbohydrates

8.3.U13:  Ribulose bisphosphate is reformed using ATP

8.3.A1:  Calvin’s experiment to elucidate the carboxylation of RuBP

8.3.NOS: Developments in scientific research follow improvements in apparatus- sources of 14C and autoradiography enabled Calvin to elucidate the pathways of carbon fixation

TOK:  the lollipop experiment used to work out the biochemical details of the Calvin Cycle shows considerable creativity.  To what extent is the creation of an elegant protocol similar to the creation of a work of art?

4 Limiting Factors

2.9.U6:  Temperature, light intensity and carbon dioxide concentration are possible limiting factors on the rate photosynthesis

2.9.S1:  Design an experiment to investigate the effect of limiting

Utilization:  the Global Artificial Photosynthesis (GAP) project aims to create an artificial “leaf” within the next decade. An electronic version of the leaf that creates oxygen and hydrogen from water and sunlight

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factors on photosynthesis

2.9.NOS:  Experimental design- controlling relevant variables in photosynthesis experiments is essential

has already been invented and will be developed for use in the next decade.

     

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UNIT 3: 9.1: PLANTS: TRANSPORT IN THE XYLEM OF PLANTS

IB topic(s):  9.1 and 9.2Essential Idea(s):  Structure and function are correlated in the xylem in plants.

Unit Length:  5 daysLesson

Topic Days

Statement(s) and Objective(s)

Skills/ Activities

1 Xylem structure

1 9.1.S1:  Drawing the structure of primary xylem vessels in sections of stems based on microscope images.

9.2.S2:  Identification of xylem and phloem in microscope images of stem and root

Aim 6:  measurement of stomatal apertures and the distribution of stomata using leaf casts, including replicate measurements to enhance reliability

2 Xylem function

1 9.1.U1:  Transpiration is the inevitable consequence of gas exchange in the leaf

9.1.U2:  Plants transport water from the roots to the leaves to replace losses from transpiration

9.1.U5:  Active uptake of mineral ions in the roots causes absorption of water by osmosis

9.1.U4:  The adhesive property of water and evaporation generate tension forces in leaf cell walls

9.1.U3:  The cohesive property of water and the structure of the xylem vessels allow transport under tension

9.1.A2:  Models of water transport in xylem using simple apparatus including blotting or filter paper, porous pots and capillary tubing

9.1.NOS:  Use models as representations of the real world-mechanisms involved in water transport in the

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xylem can be investigated using apparatus and material that show similarities in structure to plant tissues

3 Transpiration lab

2 9.1.S2:  Measurement of transpiration rates using photometers (Practical 7)

9.1.S3:  Design of an experiment to test hypothesis about the effects of temperatures or humidity on transpiration rates

4 Adaptations

1 9.1.A1:  Adaptations of plants in deserts and in saline soils for water conservation

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IB 9.2:  PHLOEM STRUCTURE AND FUNCTION         IB topic(s):  9.2Essential Idea(s):  Structure and function are correlated in the phloem in plants.Unit Length:  3 daysLesson

Topic Days

Statement(s) and Objective(s)

Skills/ Activities

1 Phloem structure

1 9.2.A1:  Structure-function relationships of phloem sieve tubes

9.2.S2:  Identification of xylem and phloem in microscope images of stem and root

2 Phloem function

2 9.2.U1:  Plants transport organic compounds from sources to sinks

9.2.NOS:  Developments in scientific research follow improvements in apparatus-experimental methods for measuring phloem transport rates using aphid stylets and radioactively-labelled carbon dioxide were only possible when radioisotopes became available

9.2.U3:  Active transport is used to load organic compounds into phloem sieve tubes at the source

9.2.U4:  High concentrations of solutes in the phloem at the source lead to water uptake by osmosis

9.2.U2:  Incompressibility of water allows transport along hydrostatic pressure gradients

9.2.U5:  Raised by hydrostatic pressure causes the contents of the phloem to flow toward sinks

9.2.S1:  Analysis of data from experiments measuring phloem transport rates using aphid stylets and radioactively-labelled carbon dioxide

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IB 9.3:  PLANT RESPONSE AND GROWTH                      Essential Idea(s):  Plants adapt their growth to environmental conditions.Unit Length:  6 daysLesson

Topic Days

Statement(s) and Objective(s) Skills/ Activities

1 Meristems

1 9.3.U1:  Undifferentiated cells in the meristems of plants allow indeterminate growth

9.3.U2:  Mitosis and cell division in the shoot apex provide cells needed for extension of the stem and development of leaves

2 Plant hormones

2 9.3.U3:  Plant hormones control growth in the shot apex (auxin is the only named hormone expected)

9.3.A1:  Micropropagation of plants using tissue from the shoot apex nutrient agar gels and growth hormones

9.3.A2:  Use of micropropagation for rapid bulking up of new varieties, production of virus-free strains of existing varieties and propagation of orchids and other rare species

9.3.NOS:  Developments in scientific research follow improvements in analysis and education-improvements in analytical techniques allowing the detection of trace amounts of substances has led to advances in the understanding of plant hormones and their effect on gene expression.

TOK:  plants communicate chemically both internally and externally.  To what extent can plants be said to have language?

3 Tropisms

1 9.3.U4:  Plant shoots response to the environment by tropisms

9.3.U5:  Auxin efflux pumps can set up concentration gradients of auxin in plants tissue

9.3.U6:  Auxin influences of cell growth rates by changing the pattern of gene expression

4 Cloning 2 3.5.U6:  Many plants species and some animal species have natural methods of cloning

3.5.S1:  Design of an experiment to assess one factor affecting the rooting of stem-cuttings (in water or solid medium)

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IB 9.4:  ANGIOSPERM REPRODUCTION        Essential Idea(s):  Reproduction in flowering plants is influenced by the biotic and abiotic environments.Unit Length:  6 daysLesson

Topic Days

Statement(s) and Objective(s)

Skills/ Activities

1 Flower Structure

1 9.4.S2:  Drawing of half-views of animal-pollinated flowers

2 Flowering 1 9.4.U1:  Flowering involves a change in gene expression in the shoot apex

9.4.U2:  The switch to flowering is a response to the length of light and dark periods in many plants

9.4.A1:  Methods used to induce short-day plants to flower out of season

3 Pollination and Fertilization

1 9.4.U3:  Success in plant reproduction depends on pollination, fertilization and seed dispersal

9.4.U4:  Most flowering plants use mutualistic relationships with pollinators in sexual reproduction

Utilization:  87 of the 115 leading global crops depend to some degree upon animal pollination. This accounts for 1/3 of crop production globally.

4 Seeds 1 9.4.S1:  Drawing internal structure of seeds

5 Germination

2 9.4.S3:  Design of experiments to test hypothesis about factors affecting germination

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UNIT 4: ECOLOGYIB 4.1 (and 9.4): SPECIES, COMMUNITIES AND ECOSYSTEMS ECOLOGY Essential Idea(s):  The continued survival of living organisms including humans depends on sustainable communities.

Lesson

Topic Days

Statement(s) and Objective(s)

Skills/ Activities

1 Community

1 4.1.U7:  A community is formed by populations of different species living together and interacting with each other

9.4.U3:  Most flowering plants use mutualistic relationships with pollinators in sexual reproduction

4.1.S2:  Testing for association between two species using the chi-squared test with data obtained from quadrat sampling (students should obtain data themselves; in each quadrat, the presence or absence of the chosen species should be recorded)

2 Ecosystem

1 4.1.U8:  A community forms an ecosystem by its interactions with the abiotic environment

4.1.U11:  Ecosystems have the potential to be sustainable over long periods of time

9.4.NOS:  Paradigm shift-more than 85% of the world’s 250,000 species of flowering plant depend on pollinators for reproduction. This knowledge has led to protecting entire ecosystems rather than individual species

International Mindedness: the need for sustainability could be discussed and the methods needed to promote this

4.1.S3:  Setting up  sealed mesocosms to try to establish sustainability (Practical 5)

3 Modes of nutrition

1 4.2.U3:  Chemical energy in carbon compounds flows through food chains by means of feeding

4.1.U3:  Species have either an autotrophic or heterotrophic method of nutrition ( a few species have both methods)

4.1.U4:  Consumers are heterotrophs that feed on living organisms by ingestion.

4.1.S1:  Classifying species as autotrophs, consumers, detritivores or saprotrophs from a knowledge of their mode of nutrition

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4.1.U5:  Detritivores are heterotrophs that obtain organic nutrients from detritus by internal digestion.

4.1.U6: Saprotrophs are heterotrophs that obtain organic nutrients from dead organic matter by external digestion.

4.1.NOS: Looking for patterns, trends and discrepancies- plants and algae are mostly autotrophic but some are not

     

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IB 4.2: ENERGY FLOW IN ECOSYSTEMSEssential Idea(s):  Ecosystems require a continuous supply of energy to fuel life processes and to replace energy lost as heat.Unit Length:   4 daysLesson

Topic Statement(s) and Objective(s)

Skills/ Activities

1 Sun as ultimate energy source

4.2.U1:  Most ecosystems rely on a supply of energy from sunlight

4.2.U2:  Light energy is converted to chemical energy in carbon compounds by photosynthesis

2 Trophic levels

4.2.S1:  Quantitative representations of energy flow using pyramids of energy (drawn to scale, stepped, not triangular. Use terms producer, primary consumer, secondary consumer…Pyramids of numbers and biomass are not required, however students should know that biomass decreases along food chains due to loss of CO2, H20 and urea).

3 Loss of heat

4.2.U4:  Energy released from carbon compounds by respiration is used in living organisms and converted to heat

4.2.U5:  Living organisms cannot convert heat to other forms of energy

4.2.U6:  Heat is lost from ecosystems

4.2.U7:  Energy losses between trophic levels restrict the length of food chains and the biomass of higher trophic levels

4.2.NOS:  Use theories to explain natural phenomena- the concepts of

International Mindedness:  the energetics of food chains is a factor in the efficiency of food production for the alleviation of world hunger.

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energy flow explains the limited length of food chains

IB 4.3: CARBON AND NUTRIENT CYCLES IB topic(s):  4.1 and 4.3Essential Idea(s): Continued availability of carbon in ecosystems depends on carbon cycling.

Lesson

Topic Days

Statement(s) and Objective(s) Skills/ Activities

1 Nutrient Cycles

1 4.1.U9:  Autotrophs and heterotrophs obtain inorganic nutrients from the abiotic environment.

4.1.U10:  The supply of inorganic nutrients is maintained by nutrient recycling (distinction between energy flow and nutrient cycling should be stressed)

2 Carbon Cycle

1 4.3.NOS:  Making accurate, quantitative measurements-it is important to obtain reliable data on the concentrations of carbon dioxide and methane in the atmosphere

4.3.A1:  Estimation of carbon fluxes due to processes in the carbon cycle (in gigatonnes)

4.3.S1:  Construct a diagram of the carbon cycle

3 Carbon Dioxide

1 4.3.U3:  Carbon dioxide diffuses from the atmosphere or water into autotrophs

4.3.U2:  In aquatic ecosystems carbon is present as dissolved carbon dioxide and hydrogen carbonate ions

4.3.U1:  Autotrophs convert carbon dioxide into carbohydrates and other carbon compounds

4.3.A2:  Analysis of data from air monitoring stations to explain annual fluctuations

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4.3.U4:  Carbon dioxide is produced by respiration and diffuse out of organisms into water or the atmosphere

4 Methane

1 4.3.U5:  Methane is produced from organic matter in anaerobic conditions by methanogenic archaea and some diffuses into the atmosphere or accumulates in the ground

4.3.U6:  Methane is oxidized to carbon dioxide and water in the atmosphere

5 Organic material

1 4.3.U7:  Peat forms when organic matter is not fully decomposed because of acidic and/or anaerobic conditions in waterlogged soils

4.3.U8:  Partially decomposed organic matter from past geological eras was converted either into coal or into oil and gas that accumulate in porous rocks

4.3.U9:  Carbon dioxide is produced by combustion of biomass and fossilized organic matter

4.3.U10:  Animals such as reef-building corals and Mollusca have hard parts that are composed of calcium carbonate and can become fossilized in limestone

·         

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IB 4.4: CLIMATE CHANGE         IB topic(s):  4.4Essential Idea(s):  Concentrations of gases in the atmosphere affect climates experienced at the Earth’s surface.

Lesson

Topic Days

Statement(s) and Objective(s)

Activities

1 Greenhouse Effect

1 4.4.U1:  Carbon dioxide and water vapour are the most significant greenhouse gases

4.4.U2:  Other gases including methane and nitrogen oxides have less impact

4.4.U3:  The impact of a gas depends on its ability to absorb long wave radiation as well as on its concentration in the atmosphere

4.4.U4:  The warmed Earth emits longer wavelength radiation (heat)

4.4.U5:  Longer wave radiation is absorbed by greenhouse gases that retain the heat in the atmosphere

2 Relationship to Global Temperature

1 4.4.U6:  Global temperatures and climate patterns are influenced by concentrations of greenhouse gases

4.4.A1:  Correlations between global temperatures and carbon dioxide concentrations on Earth

Aim 7:  databases can be used to analyze concentrations of greenhouse gases

3 Relationship to Industrialization

1 4.4.U7:  There is a correlation between rising atmospheric concentrations of carbon dioxide since the start of the industrial revolution 200 years ago and average global

International Mindedness: release of greenhouse gases occurs locally but has global impacts, so international cooperation to reduce emissions is essential.

TOK:  the precautionary

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temperatures

4.4.U8:  Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter.

4.4.A2:  Evaluating claims that human activities are not causing climate change

4.4.NOS: Assessing claims- assessment of the claims that human activities are producing climate change

principle is meant to guide decision making in conditions where a lack of certainty exists.  Is certainly ever possible in the natural sciences?

Aim 8:  there are interesting parallels between humans that are unwilling to reduce their carbon footprint and cheating in social animals when the level of cheating arises above a certain level social behavior breaks down.

4 Effects on Corals

1 4.4.A3:  Threats to coral reefs from increasing concentrations of dissolved carbon dioxide

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UNIT 1: CELLULAR RESPIRATION Estimate of timing:  3 days

COURSE BOOK: TOPICs 2.8 (SL: 122 – 129) and 8.2 (HL: 373 – 388)

ESSENTIAL IDEAS: Cell respiration supplies energy for the functions of life Energy is converted to a usable form in cell respiration

ANAEROBIC RESPIRATIONUNDERSTANDING - CORE 2.8.U1:  Cell respiration is the controlled release of energy from organic

compounds to produce ATP (details of metabolic pathways are not needed; substrates and final waste products should be shown)

2.8.U2:  ATP from cell respiration is immediately available as a source of energy in the cell

2.8.U3:  Anaerobic cell respiration gives a small yield of ATP from glucose 2.8.U4:  Aerobic cell respiration requires oxygen and gives a large yield of

ATP from glucose

UNDERSTANDING - HL8.2.U2:  Phosphorylation of molecules makes them less stable8.2.U1:  Cell respiration involves the oxidation and reduction of electron carriers8.2.U4:  Glycolysis gives a small net gain of ATP without the use of oxygen8.2.U3:  In glycolysis, glucose is converted to pyruvate in the cytoplasm (names of intermediate compounds not required)

APPLICATIONS 2.8.A1:  Use of anaerobic cell respiration in yeasts to produce ethanol and carbon dioxide in baking2.8.A2:  Lactate production in humans when anaerobic respiration is used to maximize the power of muscle contractions

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UNIT 3: AEROBIC RESPIRATION (ALL HL):  Estimate of timing:  6 days

UNDERSTANDING 8.2.U5:  In aerobic cell respiration pyruvate is decarboxylated and oxidized,

and converted into acetyl compound and attached to coenzyme A to form acetyl coenzyme A in the link reaction

8.2.U6:  In the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon dioxide (names of intermediate compounds are not required)

8.2.U7:  Energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD

8.2.U8:  Transfer of the electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping

8.2.U9:  In chemiosmosis protons diffuse through ATP synthase to generate ATP

8.2.U10:  Oxygen is needed to bind with the free protons to maintain the hydrogen gradient, resulting in the formation of water

8.2.U11:  The structure of the mitochondrion is adapted to the function it performs

SKILLS 2.8.S1:  Analysis of results from experiments involving measurement of

respiration rates in germinating seeds or invertebrates using a respirometer (students should know that an alkali is used to absorb CO2 so reductions in volume are due to O2 use.  Temperature should be controlled to avoid volume changes due to temperature fluctuations.

8.2.S1:  Analysis of diagrams of the pathways of aerobic respiration to decide where  decarboxylation and oxidation reactions occur

8.2.S2:  Annotations of a diagram of mitochondrion to indicate the adaptations to its function

APPLICATIONS8.2.A1:  Electron tomography used to produce images of active mitochondria

NATURE OF SCIENCE 2.8.NOS:  Assessing the ethics of scientific research- the use of invertebrates

in respirometers experiments 8.2.NOS:  Paradigm shift-chemiosmotic theory led to a paradigm shift in the

field of bioenergetics

THEORY OF KNOWLEDGEPeter Mitchell’s chemiosmotic theory encountered years of opposition before it was finally accepted.  For what reasons does falsification not always result in an immediate acceptance of new theories or a paradigm shift?

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UNIT 2: PHOTOSYNTHESIS Estimate of timing:  10 days

COURSE BOOK: TOPICs 2.9 (129 - 140) and 8.3 (389 - 402)

ESSENTIAL IDEAS:  Photosynthesis uses the energy in sunlight to produce the chemical energy needed for life / Light energy is converted into chemical energy

UNDERSTANDINGS (CORE) 2.9.U1:  Photosynthesis is the production of carbon compounds in cells using

light energy 2.9.U2:  Visible light has a range of wavelengths with violet the shortest

wavelength and red the longest (400-700 nm = visible light.  Don’t need to know specific wavelength for each color)

2.9.U3:  Chlorophyll absorbs red and blue light most effectively and reflects green light more than other colours

2.9.U4:  Oxygen is produced in photosynthesis from the photolysis of water 2.9.U5:  Energy is needed to produce carbohydrates and other carbon

compounds from carbon dioxide 2.9.U6:  Temperature, light intensity and carbon dioxide concentration are

possible limiting factors on the rate photosynthesis

SKILLS (CORE) 2.9.S1:  Drawing an absorption spectrum for chlorophyll and an action

spectrum for photosynthesis 2.9.S3:  Separation of photosynthetic pigments by chromatograph (Practical 4)

UNDERSTANDINGS (HL) 8.3.U1:  Light-dependent reactions take place in the intermembrane space of

the thylakoids 8.3.U4:  Absorption of light by photosystems generates excited electrons 8.3.U5:  Photolysis of water generates electrons for use in the light-

independent reactions 8.3.U6:  Transfer of excited electrons occurs between carriers in thylakoid

membranes Aim 6:  Hill’s method of demonstrating electron transfer in chloroplasts by

observing DCPIP reductions 8.3.U3:  Reduced NADP and ATP are produced in the light-dependent reactions 8.3.U9:  Excited electrons from Photosytem I are used to reduce NADP 8.3.U7:  Excited electrons from Photosytem II are used to contribute to

generate a proton gradient 8.3.U8:  ATP synthase in thylakoids generates ATP using the proton gradient 8.3.U2:  Light –independent reactions take place in the stroma 8.3.U10:  In the light-independent reaction a carboxylase catalyses the

carboxylation of ribulose-bisphosphate 8.3.U11:  Glycerate 3-phosphate is reduced to triose phosphate using a

reduced NADP and ATP 8.3.U12:  Triose phosphate is used to regenerate RuBP and produce

carbohydrates 8.3.U13:  Ribulose bisphosphate is reformed using ATP 8.3.U14:  The structure of the chloroplast is adapted to its function in

photosynthesis

SKILLS 2.9.S2:  Design an experiment to investigate the effect of limiting factors on

photosynthesis 8.3.S1:  Annotation of a diagram to indicate the adaptations of a chloroplast to

its function

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APPLICATIONS 2.9.A1:  Changes to the Earth’s atmosphere, oceans and rock deposition due

to photosynthesis 8.3.A1:  Calvin’s experiment to elucidate the carboxylation of RuBP

NATURE OF SCIENCE 2.9.NOS:  Experimental design- controlling relevant variables in

photosynthesis experiments is essential (3.1)Utilization:  the Global Artificial Photosynthesis (GAP) project aims to create an artificial “leaf” within the next decade.  An electronic version of the leaf that creates oxygen and hydrogen from water and sunlight has already been invented and will be developed for use in the next decade. 8.3.NOS: Developments in scientific research follow improvements in

apparatus- sources of 14C and autoradiography enabled Calvin to elucidate the pathways of carbon fixation (1.8)

THEORY OF KNOWLEDGEThe lollipop experiment used to work out the biochemical details of the Calvin Cycle shows considerable creativity.  To what extent is the creation of an elegant protocol similar to the creation of a work of art?

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UNIT 3: PLANT SCIENCETRANSPORT IN THE XYLEM OF PLANTS Estimate of timing:  5 daysCOURSE BOOK: TOPIC 9.1 ( 403 – 411)ESSENTIAL IDEA: Structure and function are correlated in the xylem in plants

UNDERSTANDINGS 9.1.U1:  Transpiration is the inevitable consequence of gas exchange in the

leaf 9.1.U2:  Plants transport water from the roots to the leaves to replace losses

from transpiration 9.1.U5:  Active uptake of mineral ions in the roots causes absorption of

water by osmosis 9.1.U3:  The cohesive property of water and the structure of the xylem

vessels allow transport under tension 9.1.U4:  The adhesive property of water and evaporation generate tension

forces in leaf cell walls

SKILLS 9.2.S1:  Identification of xylem and phloem in microscope images of stem and

root 9.1.S1:  Drawing the structure of primary xylem vessels in sections of stems

based on microscope images 9.1.S3: Measurement of transpiration rates using potometers.

(Practical 7) 9.1.S4: Design of an experiment to test hypothesis about the effects of

temperatures or humidity on transpiration rates.

APPLICATIONS 9.1.A1: Adaptations of plants in deserts and in saline soils for water

conservation 9.1.2:  Models of water transport in xylem using simple apparatus including

blotting or filter paper, porous pots and capillary tubing

NATURE OF SCIENCE 9.1.NOS:  Use models as representations of the real world-mechanisms involved in water transport in the xylem can be investigated using apparatus and material that show similarities in structure to plant tissues. ( 1.10)

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TOPIC 9.2: TRANSPORT IN THE PHLOEM OF PLANTS Estimate of timing: 3 daysCOURSE BOOK: TOPIC 9.2 (412 - 421)

Essential idea:  Structure and function are correlated in the phloem in plants.

UNDERSTANDINGS 9.2.U1:  Plants transport organic compounds from sources to sinks 9.2.U3:  Active transport is used to load organic compounds into phloem sieve

tubes at the source 9.2.U4:  High concentrations of solutes in the phloem at the source lead to

water uptake by osmosis 9.2.U2:  Incompressibility of water allows transport along hydrostatic pressure

gradients 9.2.U5:  Raised by hydrostatic pressure causes the contents of the phloem to

flow toward sinks

SKILLS 9.2.S2:  Analysis of date from experiments measuring phloem transport rates

using aphid stylets and radioactively-labelled carbon dioxide

APPLICATIONS9.2.A1:  Structure-function relationships of phloem sieve tubes

NATURE OF SCIENCE9.2. Developments in scientific research follow improvements in apparatus-experimental methods for measuring phloem transport rates using aphid stylets and radioactively-labelled carbon dioxide were only possible when radioisotopes became available ( 1.8)

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TOPIC 9.3: PLANT GROWTH:  Estimate of timing:  4 daysCOURSE BOOK: TOPIC 9.2 ( 422 -428 )ESSENTIAL IDEA: Plants adapt their growth to environmental conditions. UNDERSTANDINGS 3.U1:  Undifferentiated cells in the meristems of plants allow indeterminate

growth 9.3.U2:  Mitosis and cell division in the shoot apex provide cells needed for

extension of the stem and development of leaves 9.3.U3:  Plant hormones control growth in the shoot apex (auxin is the only

named hormone expected) 9.3.U4:  Plant shoots response to the environment by tropisms 9.3.U5:  Auxin efflux pumps can set up concentration gradients of auxin in

plants tissue 9.3.U6: Auxin influences cell growth rates by changing the pattern of gene

expression

APPLICATIONS 9.3.A1:  Micropropagation of plants using tissue from shoot apex nutrient agar

gels and growth hormones 9.3.A2:  Use of micropropagation for rapid bulking up of new varieties,

production of virus-free strains of existing varieties and propagation of orchids and other rare species

NATURE OF SCIENCE9.3.NOS:  Developments in scientific research follow improvements in analysis and deduction-improvements in analytical techniques allowing the detection of trace amounts of substances has led to advances in the understanding of plant hormones and their effect on gene expression (1.8)

THEORY OF KNOWLEDGEPlants communicate chemically both internally and externally.  To what extent can plants be said to have language?

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TOPIC 9.4 PLANT REPRODUCTION:  Estimate of timing:  3 daysCOURSE BOOK: TOPIC 9.3 ( 429 - 438 )Essential idea: Reproduction in flowering plants is influenced by the biotic and abiotic environments.

UNDERSTANDINGS 9.4.U1:  Flowering involves a change in gene expression in the shoot apex 9.4.U2:  The switch to flowering is a response to the length of light and dark

periods in many plants 9.4.U3:  Success in plant reproduction depends on pollination, fertilization and

seed dispersal (know differences between, but not details of) 9.4.U4:  Most flowering plants use mutualistic relationships with pollinators

in sexual reproduction Utilization:  87 of the 115 leading global crops depend to some degree upon

animal pollination.  This accounts for 1/3 of crop production globally. 3.5.U6:  Many plants species and some animal species have natural methods

of cloning

SKILLS 3.5.S1:  Design of an experiment to assess one factor affecting the rooting of

stem-cuttings (in water or solid medium) 9.4.S1:  Drawing internal structure of seeds 9.4.S2:  Drawing of half-views of animal-pollinated flowers 9.4.S3:  Design of experiments to test hypothesis about factors affecting

germination

APPLICATIONS9.4.A1:  Methods used to induce short-day plants to flower out of season

NATURE OF SCIENCE9.4. Paradigm shift-more than 85% of the world’s 250,000 species of flowering plant depend on pollinators for reproduction. This knowledge has led to protecting entire ecosystems rather than individual species (2.3)

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UNIT 4: ECOLOGYTOPIC 4.1: SPECIES, COMMUNITIES AND ECOSYSTEMS ECOLOGY: Estimate of timing:  3 days

COURSE BOOK: TOPIC 4.1 ( 201 - 212 )ESSENTIAL IDEA: The continued survival of living organisms including humans depends on sustainable communities.

UNDERSTANDINGS 4.1.U7:  A community is formed by populations of different species living

together and interacting with each other 4.1.U8:  A community forms an ecosystem by its interactions with the abiotic

environment 4.1.U11:  Ecosystems have the potential to be sustainable over long periods of

time SKILLS 4.1.S2:  Setting up  sealed mecocosms to try to establish

sustainability (Practical 5) 4.1.S3:  Testing for association between two species using the chi-squared test

with data obtained from quadrat sampling (students should obtain data themselves; in each quadrat, the presence or absence of the chosen species should be recorded)

NATURE OF SCIENCEInternational Mindedness: The need for sustainability could be discussed and the methods needed to promote this

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TOPIC 4.1: ENERGY FLOW:  Estimate of timing:  7 daysCOURSE BOOK: TOPIC 4.1 (213 - 219)ESSENTIAL IDEA: Ecosystems require a continuous supply of energy to fuel life processes and to replace energy lost as heat.

UNDERSTANDINGS 4.1.U3:  Species have either an autotrophic or heterotrophic method of

nutrition (a few species have both methods) 4.2.U1:  Most ecosystems rely on a supply of energy from sunlight 4.2.U2:  Light energy is converted to chemical energy in carbon compounds by

photosynthesis 4.2.U3:  Chemical energy in carbon compounds flows through food chains by

means of feeding 4.2.U4:  Energy released from carbon compounds by respiration is used in

living organisms and converted to heat 4.2.U5:  Living organisms cannot convert heat to other forms of energy 4.2.U6:  Heat is lost from ecosystems 4.2.U7:  Energy losses between trophic levels restrict the length of food chains

and the biomass of higher trophic levels

SKILLS 4.1.S1:  Classifying species as autotrophs, consumers, detrivores or

saprotrophs from a knowledge of their mode of nutrition 4.2.S1:  Quantitative representations of energy flow using pyramids of energy

(drawn to scale, stepped, not triangular.  Use terms producer, primary consumer, secondary consumer.  Pyramids of numbers and biomass are not required, however students should know that biomass decreases along food chains due to loss of CO2, H20 and urea).

NATURE OF SCIENCE4.1.NOS: Looking for patterns, trends and discrepancies- plants and algae are mostly autotrophic but some are not (3.1)4.2.NOS:  Use theories to explain natural phenomena- the concepts of energy flow explains the limited length of food chains International Mindedness:  the energetics of food chains is a factor in the efficiency of food production for the alleviation of world hunger.

TOPIC 4.3: CARBON AND NUTRIENT CYCLES:  Estimate of timing:  6 daysCOURSE BOOK: TOPIC 4.3 (220 - 228 )ESSENTIAL IDEA: Continued availability of carbon in ecosystems depends on carbon cycling.

UNDERSTANDINGS 4.1.U10:  The supply of inorganic nutrients is maintained by nutrient

recycling (distinction between energy flow and nutrient cycling should be stressed)

4.3.U2:  In aquatic ecosystems carbon is present as dissolved carbon dioxide and hydrogen carbonate ions

4.3.U3:  Carbon dioxide diffuses from the atmosphere or water into autotrophs 4.3.U1:  Autotrophs convert carbon dioxide into carbohydrates and other

carbon compounds 4.3.U4:  Carbon dioxide is produced by respiration and diffuses out of

organisms into water or the atmosphere 4.3.U5:  Methane is produced from organic matter in anaerobic conditions by

methanogenic archaeans and some diffuses into the atmosphere or accumulates in the ground

4.3.U6:  Methane is oxidized to carbon dioxide and water in the atmosphere

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4.3.U7:  Peat forms when organic matter is not fully decomposed because of acidic and/or anaerobic conditions in waterlogged soils

4.3.U8:  Partially decomposed organic matter from past geological eras was converted either into coal or into oil and gases that accumulate in porous rocks

4.3.U9:  Carbon dioxide is produced by combustion of biomass and fossilized organic matter

4.3.U10:  Animals such as reef-building corals and Mollusca have hard parts that are composed of calcium carbonate and can become fossilized in limestone

SKILLS4.3.S1:  Construct a diagram of the carbon cycle

APPLICATIONS 4.3.A1:  Estimation of carbon fluxes due to processes in the carbon cycle (in

gigatonnes) 4.3.A2:  Analysis of data from air monitoring stations to explain annual

fluctuations

NATURE OF SCIENCE4.3: Making accurate, quantitative measurements-it is important to obtain reliable data on the concentrations of carbon dioxide and methane in the atmosphere (3.1)

TOPIC 4.4: CLIMATE CHANGE:  Estimate of timing:  5 days

ESSENTIAL IDEA: Concentrations of gases in the atmosphere affect climates experienced at the Earth’s surface.

COURSE BOOK: TOPIC 4.4 ( 229 - 240 )

UNDERSTANDINGS 4.4.U1:  Carbon dioxide and water vapour are the most significant

greenhouse gases 4.4.U2:  Other gases including methane and nitrogen oxides have less

impact 4.4.U3:  The impact of a gas depends on its ability to absorb long wave

radiation as well as on its concentration in the atmosphere 4.4.U4:  The warmed Earth emits longer wavelength radiation (heat). 4.4.U5:  Longer wave radiation is absorbed by greenhouse gases that retain

the heat in the atmosphere 4.4.U6:  Global temperatures and climate patterns are influenced by

concentrations of greenhouse gases 4.4.U7:  There is a correlation between rising atmospheric concentrations of

carbon dioxide since the start of the industrial revolution 200 years ago and average global temperatures

4.4.U8:  Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter

APPLICATIONS 4.4.A1:  Threats to coral reefs from increasing concentrations of dissolved

carbon dioxide 4.4.A2:  Correlations between global temperatures and carbon dioxide

concentrations on Earth Aim 7:  databases can be used to analyze concentrations of greenhouse gases 4.4.A3:  Evaluating claims that human activities are not causing climate

change

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NATURE OF SCIENCE 4.4: Assessing claims- assessment of the claims that human activities are

producing climate change (5.2) International Mindedness:  release of greenhouse gases occurs locally but has

global impacts, so international cooperation to reduce emissions is essential. TOK:  the precautionary principle is meant to guide decision making in

conditions where a lack of certainty exists.  Is certainty ever possible in the natural sciences?

Aim 8:  there are interesting parallels between humans that are unwilling to reduce their carbon footprint and cheating in social animals when the level of cheating arises above a certain level social behavior breaks down.

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