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Banjos to biodiesel – linking products to photosynthesis Teaching notes
Working in pairs/groups, students are given all the 'structure', 'use' and 'function' words all jumbled up together. They are asked to sort the words into three groups. Suggested groupings:
Plant structures: bark, bulbs, corms, flowers, fruit, leaves, nuts, phloem, roots,
seeds, sprouting seeds, stems, thorns, trunk, tubers, xylem.
Uses of plants: adhesives, biofuels, bioplastics, boats, construction, cosmetics,
decorations, dyes, food, fuel, medicines, musical instruments, paper, perfumes, rope,
sports, textiles, tools, varnish.
Functions of plant cells, tissues and organs: absorption, growth, photosynthesis,
protection, reproduction, respiration, storage, support, transport.
They are asked to discuss what might be a connection between all the words. From plants we can make all these materials as well as eating them. Move the discussion on to what process/product is at the heart of all these things. Photosynthesis and glucose. www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Explain that they are going to decide how glucose is linked to the wide range of 'uses' by giving examples of many of the uses: e. g. Lavender is used in perfume. What part of the plant is used? How does this link to glucose? The plant uses glucose to make the chemicals in the perfume. To stimulate their ideas, 6 examples are provided which give some unusual and contemporary uses of plants. Groups can work on this for a few minutes before being introduced to the 'fact cards' which provide more detailed information about certain parts of the plant. Cellulose makes up cell walls and so relates to all parts of the plant; lignin occurs where strength and/or water resistance is needed; plant saps are found in and around plant cells and in xylem and phloem; plant proteins are required for growth so are found in growing tips and seeds and are stored; plant oils and starch are stores of energy for the plant, although fats are an essential part of cell membranes. www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Cut out the keywords and sort them into three groups. Discuss the connections between the words in each group. www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Task 2

Plants photosynthesise to produce glucose. How is glucose linked to the wide range of
uses of plants?
Choose six plants and their uses and fil in the table below. There are some information
cards to help.
Part of plant used How does this link to glucose Plant uses glucose to make the chemicals in perfume. www.teachitscience.co.uk 2014

Banjos to biodiesel – linking products to photosynthesis Information cards – plants and their uses
Galantamine is a drug used to treat Alzheimer's disease. It is found in plant sap in the leaves Daffodil
and bulbs of daffodils and is thought to protect the plant from grazing animals. Daffodils are grown on farms in the Black Mountains, Wales. 10 tons of bulbs yield 1 kg of galantamine. Aloe vera has been used for more than 3 000 years. It is cultivated worldwide, primarily as a crop for "Aloe gel", which comes from the leaf. Today, it is used in: food - as a natural flavouring, cosmetics, food supplements and herbal remedies. Aloe latex contains anthraquinones, compounds that are used in healing and reducing pain because of their natural anti-inflammatory A study published in General Dentistry reported that Aloe vera in tooth gel is as effective as toothpaste in controlling cavity-causing oral The botanical name of abaca is Musa Textilis, a tree-like herb which is of the same genus as the common banana which it closely resembles. It is indigenous to the Philippines. Car manufacturers have used a mixture of polypropylene thermoplastic and abaca yarn in car body parts. Production of abaca fibre from cellulose and lignin uses an estimated 60% less energy than production of glass fibre and is Cherrie Mio Rhodes 2011 biodegradable over time. www.teachitscience.co.uk 2014

Banjos to biodiesel – linking products to photosynthesis Evening primrose oil is extracted from seeds of the evening primrose plant (Oenothera biennis) - a wild flower that grows in eastern and central Originally, evening primrose was used by Native Americans to make poultices and heal wounds. It was also traditionally eaten and used as a leaf primrose
Nowadays evening primrose is mainly used for the production of its oil, which is commonly used to help reduce the pains associated with menstruation and for its therapeutic benefits for David Short 2011 https://flic.kr/p/acy1qT the skin of the face. Why cut down a 40 to 100 year old tree when bamboo stems can provide one of the hardest building materials there is and grow an average of 50 centimetres a day? Indeed, bamboo is the fastest growing woody plant in the world. Some species can grow as much as 121 centimetres in a 24-hour period. Stronger than steel, bamboo grows like a weed and can be a very viable building material. Soya bean oil is used to produce flexible foam. Such foams were first used in automobile seating, then upholstered furniture and then mattresses and pillows. The first generation of these foams had an odour and, unlike petrochemicals, plant–based oils can turn rancid. Second and third generations products have been modified at the molecular level to produce odourless foams. ricoeurian 2006 https://flic.kr/p/r5TV9 www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Read the information cards about the different chemical substances that are found in plants. Complete the table to show the structures in plants that they relate to. Part of plant substance is found in Properties of substance Cell walls throughout the plant Link the uses of plants cards from Task 1 to the properties of the chemical substances that make them suitable for what they are used for. Plant chemical substance Construct a mind map with ‘photosynthesis and glucose' at the centre. It should show the connections between chemical substances in plants, plant structures and functions and the uses of plants. www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Information cards – substances in plants
Cellulose
The plant cell wall surrounds the cell membrane. It is made up of multiple layers of cellulose which are arranged into primary and secondary walls. Cellulose is the most common organic compound on Earth. About 33% of al plant matter is cellulose - the cellulose content of cotton is 90% and wood is 50% cellulose. Cellulose is a polymer made of repeating glucose molecules attached end to end. A cellulose molecule may be from several hundred to over 10,000 glucose units long. The cell walls of all vascular plants also contain a polymer called lignin. Lignin is water-resistant. It reinforces cell walls, keeping them from collapsing. This is particularly important in the xylem, because the column of water in the hollow xylem cells is under tension (negative pressure) and without the lignin reinforcement the cells would collapse. Lignin provides the structural strength needed by large trees to reach heights in excess of 100 m. Without lignin these trees would collapse on themselves. Also, lignin along with other cell wall constituents provides resistance to diseases, insects, cold temperatures, and other stresses. Lignin plays a crucial part in conducting water in plant stems. Plant oils
Oils produced by plants are found in seeds, nuts and some fruits. They represent a store of energy. Aromatic plant oils have evolved to attract insects. Vegetable oils consist of molecules of fatty acids and glycerol and are formed from the elements carbon, hydrogen and oxygen. These elements also make up molecules of glucose. www.teachitscience.co.uk 2014 Banjos to biodiesel – linking products to photosynthesis Plant proteins
The glucose in the leaves reacts with nitrates and other salts to form amino acids. These are then combined to make proteins that are used to form enzymes and chlorophyll in the cells. Excess amino acids are either stored in the leaves or are carried to the growing parts of the plant. Sap is the name given to fluids found in plants. There are different types of sap e.g. cell sap, xylem sap and phloem sap. Each contains different concentrations of dissolved substances. Saps are involved in the transport of sugars, amino acids and other chemical substances around the plant. Another form of sap is involved in protecting the plant from herbivores especially herbivorous invertebrates, examples include plant resins and latex. Starch is the main form in which plants store carbon. It occurs as semi‐crystalline granules composed of two polymers of glucose, called amylose and amylopectin. Starch is insoluble in water and can act as a store of carbon for a few hours, for example in leaves, or for many years as in dormant seeds. There is enormous variation in granule size and shape between plant organs, and between plant species. Starch is the major carbohydrate of nutritional importance in the diet: it is degraded to glucose by amylases in the mouth and small intestine. When cooked in water, starch forms gels or pastes that have a wide range of industrial applications in food and other industries. www.teachitscience.co.uk 2014

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