Leaves We Are Learning To (WALT) Explain how different cells and tissues in a leaf are adapted for their functions Appreciate the wide range of adaptations of leaves for different purposes What I’m Looking For (WILF) Is for you to be able to explain why a leaf is good at carrying out photosynthesis

Macroscopic

Light Microscope – like STAC’s

Electron microscope Close up of a stoma on the under side of a leaf

Another electron microscope image

Leaves On the underside of the leaf are small openings or pores called the stomata. The stomata serve as the lungs of the leaf allowing air to enter. The stomata allow the evaporation of water and the release of oxygen during the night. The outer layers of the leaf are covered with a waxy layer which prevents the leaf from drying out.

Stoma is a small hole Its size is controlled by 2 guard cells closed open

Stoma function is for gas exchange in the leaf oxygen Guard cell Provided plant is photosynthesising Carbon dioxide

Stomata open and close at different times of the day When it is light the plant needs CO2 for photosynthesis so the stoma open At night (darkness) they close

Key points Leaves are usually very thin so that sunlight and carbon dioxide can pass through easily Broad, flat surface of a leaf increases the surface area, allowing more sunlight and carbon dioxide to reach cells Stomata allow carbon dioxide to diffuse into the leaf and oxygen to diffuse out of the leaf Veins carry water and minerals around the plant

1 minute for every question! Questions – 5 minutes 1 minute for every question!

Structure of a leaf - label Palisade layer Upper epidermis Lower epidermis Waxy cuticle Mesophyll layer

Unusual leaves – Pitcher Plant It is a carnivorous plant Deep tube with slippery slides Produces a sugary nectar to attract insects Plant digest insects using enzymes – source of nitrogen which is used to make proteins

Video clips Private Life of Plants - David Attenborough New Scientist Pitcher Plant Research

Where does the sugar made in photosynthesis get its carbon atoms from? 1 2 3 Where does the sugar made in photosynthesis get its carbon atoms from? By what process do roots take up water from the soil? What are the two functions of the waxy cuticle on the upper side of a leaf? 4 5 6 What chemical does a plant cell store glucose as? Name a cell which does not contain chloroplast? Explain why? Which dilute solution is stored in the cell vacuole? For this task you need to change the questions to cover the topic you have taught as this is used as an AfL tool in the lesson. Each pupil is given a sheet and they have to go and ask different people in the room if they know the answer to the question. If they know the answer, they write down there name but not the answer yet. They cannot have the same person answer more than two questions on the sheet. When the task is finished choose random pupils to give the names of the person who knows the answer then get that pupil to share this with the class. If the class agree, write down the answer in the box. This task promotes the pupils interpersonal skills through communication and peer teaching. 7 8 9 What does this picture show? What solution do we drop on a leaf to prove the presence of starch? What change will you see? When a plant cell is full of fluid it becomes firm to support the plant. What’s another word for a plant cell full of fluid

Where does the sugar made in photosynthesis get its carbon atoms from? 1 2 3 What are the two functions of the waxy cuticle on the upper side of a leaf? Where does the sugar made in photosynthesis get its carbon atoms from? By what process do roots take up water from the soil? Water runs off leaf onto soil Prevent evaporation From carbon dioxide in the air Osmosis 4 5 6 Name a cell which does not contain chloroplast? Explain why? Which dilute solution is stored in the cell vacuole? What chemical does a plant cell store glucose as? Root hair cells, it is underground so cannot photosynthesize Cell sap Starch For this task you need to change the questions to cover the topic you have taught as this is used as an AfL tool in the lesson. Each pupil is given a sheet and they have to go and ask different people in the room if they know the answer to the question. If they know the answer, they write down there name but not the answer yet. They cannot have the same person answer more than two questions on the sheet. When the task is finished choose random pupils to give the names of the person who knows the answer then get that pupil to share this with the class. If the class agree, write down the answer in the box. This task promotes the pupils interpersonal skills through communication and peer teaching. What solution do we drop on a leaf to prove the presence of starch? What change will you see? 7 8 9 What does this picture show? When a plant cell is full of fluid it becomes firm to support the plant. What’s another word for a plant cell full of fluid 2 guard cells which make up the stoma Iodine. Change from brown to blue/black Turgid

Where is your learning going? New learning I already knew Questions I need to ask The new ofsted framework for outstanding lessons wants pupils to know what they have learned, what they already knew and where their learning is going. By using this, the questions I need to task can be used as a dialogue for written feedback in pupils books and is a great AfL example.