How can carbon dioxide produce chips?

What is happening here?

Carbon dioxide Sunlight Glucose Oxygen Water

Photosynthesis

Limiting factors What can affect the rate of photosynthesis?

Limiting factors What can affect the rate of photosynthesis? Less light = plant photosynthesises slowly Even if there is a lot of water and carbon dioxide More light = faster photosynthesis Less carbon dioxide = slower photosynthesis Even if there is a high light intensity More carbon dioxide = faster photosynthesis Too cold/too hot = slower photosynthesis Even if other variables are there Optimum temperature = faster photosynthesis

Limiting factors What can slow the rate of photosynthesis? Light Intensity Graph: Description: Carbon dioxide Graph: Description: Temperature Graph: Description:

What does the plant do it for? Glucose: -Used in respiration and growth -Stored as starch (insoluble) Oxygen: -By product (waste) -Let back out into atmosphere

Glucose 1.Energy 2.Cellulose in cell walls 3.New chlorophyll Stored as starch as it is insoluble TUBER

Create a story board to explain the journey from carbon dioxide to a chip State the word equation for photosynthesis Describe the limiting factors of photosynthesis Explain how plants use the glucose they produce in photosynthesis

Your Task Over the Christmas holidays create an exploration for the following experiment: -Investigate limiting factors on photosynthesis Choose one of the three we have learnt about Use the exploration criteria to complete this, also look at the exploration you completed for enzymes – how could you improve? Due: Tuesday 6 th January Make sure you also revise for your SAW test

2.9 Photosynthesis Understanding: -Photosynthesis is the production of carbon compounds in cells using light energy -Visible light has a range of wavelengths with violet the shortest wavelength and red the longest -Chlorophyll absorbs red and blue light most effectively and reflects green light more than other colours -Oxygen is produced in photosynthesis from photolysis of water -Energy is needed to produce carbohydrates and other carbon compounds -Temperature, light intensity and carbon dioxide concentration are possible limiting factors on the rate of photosynthesis Applications: -Changes to the Earth’s atmosphere, oceans and rock deposition due to photosynthesis Skills: -Design of experiments to investigate limiting factors on photosynthesis -Separation of photosynthetic pigments by chromatography -Drawing an absorption spectrum for chlorophyll and an action spectrum for photosynthesis Nature of science: -Experimental design: controlling relevant variables in photosynthesis experiments is essential

Photosynthesis Plants are able to make their own energy using sunlight and simple carbon compounds. Carbon dioxide + water  glucose + oxygen Energy converts from light energy to chemical energy

Wavelengths of light Light is made up of many wavelengths Some wavelengths are invisible to us

Wavelengths of light Too short to see: X-rays, UV rays Too long to see: Infrared Visible light range from 400 to 700 nanometres

Photosynthesis Wavelengths of light detected by human eye also used in photosynthesis They are the most abundant wavelengths on earth so plants have adapted to use these

Pigments Pigments are substances that absorb light – therefore appear coloured to us If a pigment absorbs all colours, it appears black as it emits no light Some pigments only absorb certain wavelengths of light

Pigments Gentian flower absorbs all colour except blue So it appears blue This part of sunlight is reflected and can pass into our eye.

Chlorophyll There are various forms of chlorophyll but they all appear green to us They absorb red and blue light Green light is absorbed less effectively so is reflected This is why plants look green!

Spectra Action Shows rate of photosynthesis at each wavelength of light Absorption Percentage of light absorbed at each wavelength of each pigment

Rules to draw spectra ActionAbsorptionBoth Y-axis should be used for rate of photosynthesis – often given as a percentage of the maximum rate (0- 100%) Y-axis should be labelled % absorption (0-100%) Horizontal axis should have label: wavelength (nm) Scale from nm for wavelength

Separating Photosynthetic pigments Chloroplasts have many types of chlorophyll and other accessory pigments Because they absorb different wavelengths of light they look different colours to us We can separate these pigments by chromatography

Separating Photosynthetic pigments A spot containing leaf pigments is placed near one end of the strip of chromatography paper A solvent is allowed to run up the strip This separates out the different types of pigment – your experiment on Tuesday

Exploration Finish exploration ready to hand in (hard copy) tomorrow in the lesson If you have already finished this – revise for your SAW exam

Revise Once you have completed your practical and your worksheet complete revision ready for your SAW test Wednesday – Test and mark during lesson (marks not taken in – for your revision!) Photosynthesis and respiration Thursday – Your own revision so bring in any resources you need