In Seeds to Provide Food for Germination of Offspring (Young Embryos)

Storage organs

Plants store food

 In Seeds to provide food for germination of offspring (young embryos)

 In fruits to be used as a means to disperse mature seeds away from parent plants. Fruits when ripe contain mature seeds. Mammals - humans, bats, other primates and birds consume fruits away from the parent plant thus dispersing seeds.

 In storage organs (leaves, stems and roots)to:

o Survive adverse periods (drought)

o Be a form of asexual reproduction (quick Growth and development into a new plant genetically identical to parent plants) specially termed vegetative propagation)

 How does all of this happen?

o During favourable periods or times of plenty (wet season or spring time)

. growth is rapid (mitotic cell division) using food from storage organs no process of germination

. food produced by photosynthesis is used to form new stores of food in new special storage organs until another unfavourable period (drought, dry season or winter) Types of storage organs and compounds

1. Bulbs - swollen leaves example onions

Onions are leaves packed with disaccharides hence their sweet taste

Longitudinal section of an onion Growing red onions

2. Fruits – these are swollen ovaries of flowers and in the case of the case of a false fruit a swollen receptacle (apple)

The storage compounds are disaccharides usually sucrose 3. Seeds

:these are fertilized ovules (eggs within the flower ovary) made up of two main parts a.i. an embryonic plant a.ii. storage tissue cotyledons and or endosperm as a food source for germination until leaves are formed and the young plant Monocot seed: like can photosynthesise any grass and Dicot seed like red grains they mainly bean: they mainly use endosperm use cotyledonous storage storage

The storage compounds of seeds in

1. cotyledons (mono or dicot) or 2. endosperm tissue:

Range from starch and lipids in most to some using protein like soya bean peas and other legumes

Special lipid stores are found in nuts and palm seeds are use by man as cooking oils, peanut butter and as scented oils.

4. roots – swollen roots packed with polymers of carbohydrates commonly the polysaccharide is starch

Carrot cortex swollen with disaccharides and Carrot swollen root complex carbohydrates forming fibre Cassava swollen roots of starch and protein

Sweet Potato swollen root tuber

5. stems – swollen underground vertical and horizontal stems usually packed with starch

a. stem tubers – irish potatoes b. corms – vertical underground stems e.g. dasheen

c. rhizome – horizontal stem e.g. ginger

a. Stem tuber b. Corms

Corm cycle e.g. dasheen

Leaves and stems used to make calallo, saheena,

Corm used as a ground provision rich in iron C. Rhizome e.g. ginger Summary view

Many plants that survive winter or dry season in a dormant state form storage organs below the ground which store nutrients during these unfavourable periods, the rest of the plant withering away. Storage organs come in a variety of forms, including tap roots, bulbs, corms, rhizomes, root tubers and stem tubers as shown in the Figure below. The carrot, the root is greatly enlarged into a fleshy tap root; the bulbs of onions are modified leaves; crocus corms, iris rhizomes and dahlia tubers are modified stems, and the tubers of potatoes are modified tips of underground stems.

(a) ______(Daucus carota, (b) ______(Allium sp.); (c) ______,

(d) ______, (e) ______(f) ______(Solanum The latest on the use of storage organs of the compound starch by humans is not for food but fuel:

1.5 gen ethanol to be China's mainstream biomass fuel Posted: October 31, 2011

 Chinese biochemical diesel target to drop, replaced by biomass fuel  University don suggests government drive biofuels development China has upped its annual consumption target for ethanol fuel to 5 million tonnes while dropping that of biochemical diesel to 1 million tonnes for the next five years. A spokesman for the National Energy Administration says this is an increase of 2 million tonnes and a drop of 500,000 tonnes, respectively, from the targets disclosed at an earlier national rural energy working conference. Director and professor at the Institute of Applied Chemistry, Department of Chemical Engineering at Tsinghua University, Liu Dehua, says when the Chinese government last set targets five years ago, the annual consumption target for non-grain ethanol fuels was set at a modest 2 million tonnes. However, even that target was difficult to reach as only 1.8 million tonnes of the fuel was consumed last year.

Cassava roots: Sweet potato, sugar grass and cassava are raw materials for 1.5- generation ethanol (photo credit: istockphoto) As for biochemical diesel, the country revised its annual consumption target for the next five years downward, mainly due to supply shortage of raw materials, especially that of waste grease. Furthermore, as the country imports 70% of its edible oils and 55% of its petroleum, it becomes much more difficult for the country to aggressively drive the development of the biochemical diesel oil sector, due to its reliance on imported raw materials. According to Liu, it is difficult to predict what the consumption patterns for 1.5- generation and second-generation grain ethanol in the country will be in the next five years. In China, cassava or sweet sorghum-based bioethenal is termed “1.5- generation ethanol”, indicating the use of starch crops in contrast to second-generation ethanol, which is produced from cellulosic raw material. However, as second-generation technology has not been industrialised in China, it is not likely to develop as the mainstream technology within the next five years. Meanwhile, 1.5-generation ethanol is expected to become the mainstream biomass fuel over the next five years. Liu also says he expects the Chinese biomass fuel sector to grow faster in the next five years compared with the previous five, and listed the following reasons: • Both domestic and foreign pressure to address climate change issues will force the Chinese government to prioritise the development of renewable energies including biomass. • The fact that fossil fuels are being consumed faster than they can be replenished alerts mankind to the necessity to develop renewable energies. • As both the government and general public pay more attention to renewable energy, a substantial amount of capital, including government subsidies and private investment, is expected to flow into the research and development (R&D) of biomass fuel-related technologies, which will directly drive technological improvement across the sector. • With these technological improvements leading to sustainable decreases in biomass fuel costs, consumers will start to choose the more affordable fuel. Accordingly to Liu, the Chinese government should drive the development of the country’s biomass fuel sector with these steps: • Reinforce policy guidance efforts and increase financial subsidies, and put in place mandatory standards. • Increase capital investment, both at the government level as well as from the private sector, in technology R&D and in pilot projects to industrialise the process. • Open the market to imports of biomass fuels, as that would help build and expand China’s biomass fuel market, and promote development across the sector. – Nanjing Shanglong Communications - See more at: http://www.greenprospectsasia.com/content/15-gen-ethanol-be- chinas-mainstream-biomass-fuel#sthash.2nW9f0TE.dpuf