Plant nutrition- Photosynthesis LO: define and write the balanced equation for photosynthesis annotate the structure of a leaf and explain how it is adapted for photosynthesis TASK: Discuss with your partner, Where did the increase in mass of this oak tree come from? Hint think of the photosynthesis equation

Wood from oak treeI all comes from carbon dioxide in the air!!!

New photosynthesis song Q’s 1. What does photosynthesis make? 2.Write and balance the photosynthesis equation _H 2 O + _CO 2 C 6 H 12 O 6 + _O 2 3. Where does the water come from? 4. Where does the carbon dioxide come from and into the leaves? 5. What absorbs the suns energy?

What is photosynthesis (light making)…really? plants make sugar (glucose) from carbon dioxide and water using energy from light.” Then make more complex materials like carbohydrates, lipids and proteins Fascinating story of photosynthesis

Chlorophyll You can’t just shine light on CO 2 and water to make glucose! The green pigment Chlorophyll traps the sun’s light energy, This energy makes CO 2 combine with H 2 O (enzymes help too!) To produce glucose (chemical energy) Chloroplast close up

Uses of glucose

Equations You must know both of these!! Chlorophyll light

How is a leaf adapted for photosynthesis? Intro to leaves

Leaf- adaptations for Photosynthesis

Microscope drawings 1.Carefully stick the nail vanished leaf to the tape. 2.Carefully separate the leaf and the tape ( the vanish should stick to the tape). 3.Set up your microscope and focus on the surface of the leaf imprint. 4.Draw a high power diagram of the one or 2 stomata. Label your diagram Label your diagram and note down the magnification used. No shading, clear lines and label with a ruler

Homework Read pages 49 to 54 Answer questions Q on Pg54 Answer questions Q on Pg56

Structure of Leaves Summary questions 1. Leaves are adapted for… a) pollinationb) photosynthesisc) photography 2.Stomata are... a) holes in a leaf that can open and close to let gases in and out b) the cells that carry out photosynthesis c) small stones found in your stomach. 3. Leaves are covered with a thin waterproof layer called the… a) popsicleb) cuticlec) waxicle 4. Leaves have a large surface area to... a) increase the rate of reactions b) catch the maximum amount of sunlight c) look pretty in parks and gardens. 5. Palisade mesophyll is in the upper part of the leaf because… a) it needs to capture as much sunlight as possible b) the lower areas were already full c) it stops the upper surface from collapsing. 6. Spongy mesophyll has large air spaces between the cells to... a)allow veins into the leaf b) cut down the amount of cellulose needed to build new cell walls c) give room for gases to move more easily.

Without light energy, the reactions of photosynthesis cannot work. TRUE! 1. Photosynthesis only happens in the light.2. Plants make food from oxygen and sunlight.3. Photosynthesis and respiration work in opposite directions. 4. Plants look green because they contain the chemical chlorophyll. 5. Roots carry out half the photosynthesis that takes place in a healthy oak tree. 6. Plants give out carbon dioxide when they are photosynthesising. True or false? 9C Photosynthesis myths? They take in carbon dioxide. Oxygen is produced by photosynthesis. FALSE! Photosynthesis produces glucose and oxygen, while respiration breaks them down to make carbon dioxide and water. TRUE! Chlorophyll absorbs all the colours in light except green – we see the green light because it is reflected from the plant. TRUE! They are vital to the plant but roots cannot carry out photosynthesis – they’re underground in the dark. FALSE! Plants need carbon dioxide from the air and water from the soil to build sugars. Oxygen is produced in photosynthesis. FALSE!

Drawing Leaf Structure Draw a labelled picture and note down the magnification used. No shading, clear lines and label with a ruler 1.View prepared slides of the lower epidermis of the leaf, and a leaf cross section 2.LOWER EPIDERMIS: drawing at 400x magnification 3.LEAF CROSS-SECTION: drawing at 100x magnification

Leaves specialised for photosynthesis

Structure of a Leaf Cuticle and upper epidermis- waterproof and transparent Lower epidermis- stomata (pores) for gas exchange Palisade mesophyll cells with many chloroplasts for photosynthesis Spongy mesophyll large air spaces for gas exchange, chloroplasts Collenchyma thickened cell walls for extra support Vascular bundle xylem transports waters phloem transports food Parenchyma unspecialised cells