Investigating+transport+systems+in+a+flowering+plant

= Orientacions per al professorat =

= = Aquesta pràctica es pot fer servir quan s'estudia la nutrició vegetal com a complement sobre la nutrició dels vegetals. Es pot fer com es mostra aquí, de forma que és una pràctica investigadora on els alumnes han de proposar diverses hipòtesis sobre com es produirà el transport del colorant o bé en format demostratiu explicant com es produeix el transport a través del xilema monitroritzant-lo gràcies al colorant alimentari. Com en totes les pràctiques en anglès, cal considerar l'opció de fer un vocabulari (no té perquè fer referència només als termes científics) abans, durant o després de la pràctica.

=Guió per a l'alumnat=

1. Introduction
It is your mother's birthday, you want to give her a special gift. Blue is her favourite colour, so you are considering to buy her a blue flower. But blue flowers are very rare and expensive. That is why you are wondering if you could make a white flower turn blue using some kind of blue dye.

2. Problema
The problem is you don't know if using a blue dye you could turn a whole flower blue or it will keep some white petals of pieces of petals with the original colour.

3. Hipothesis
Think about the things that might happen when you dye the flower. Will it change colour or will it remaing white? Will it change the colour for every part of the flower or only some parts will change their colour? According to what you have learnt during previous lectures write and hipothesis about what you should observe.

4.1. Material

 * Chrysanthemum or carnation, white, one per working group.
 * Measuring cylinders, 10 cm3, 2
 * Scalpel, 1 per working group
 * Tile (or other suitable cutting board)
 * Beaker, 100 cm3, to collect coloured water
 * Beaker, 100 cm3, to collect water
 * Plastic tray
 * Sticky tape
 * 500cm3 of water with a food dye added to it.

4.2. Procedure

 * 1) Take a white flower with a long stalk – for example, chrysanthemum or carnation. Cut the stalk carefully lengthwise; either all the way along the stalk to the base (or //receptacle//) of the flower or just part way up the stalk.
 * 2) Put each half of the stalk into a measuring cylinder containing either plain water or water to which food dye has been added.
 * 3) Tape the measuring cylinders to a plastic tray so that they don’t fall over.
 * 4) Leave for a few hours or days and observe the changes.

5.Results
In this part you will have to explain what you have observerd after the experiment. To help you a bit, try to answer this questions before using what you know from previous lectures on plant nutrition: Water and dye are passing through certain structures as they travel up the plant. Which structures are they? When they reach the flower petals, what happens to: i) the water? ii) the dye? What is the consequence of the difference in the behaviour of water and dye? What commercial applications can you think of for this procedure?

6.Discussion
In this part you will have to decide if this is a good strategy to create blue flowers for your mother's birthday.

=Referències=

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**1 **Water and dye are passing through certain structures as they travel up the plant. Which structures are they? **2 **When they reach the flower petals, what happens to: i) the water? ii) the dye? **3 **What is the consequence of the difference in the behaviour of water and dye? <span style="display: block; height: 1px; left: -40px; line-height: normal; margin: 0cm 0cm 0cm 1cm; overflow: hidden; position: absolute; text-indent: -1cm; top: 1036px; width: 1px;">**<span style="font-family: 'Arial','sans-serif';">4 **What commercial applications can you think of for this procedure? <span style="display: block; height: 1px; left: -40px; line-height: normal; margin: 0cm 0cm 0cm 1cm; overflow: hidden; position: absolute; text-indent: -1cm; top: 1036px; width: 1px;">**<span style="font-family: 'Arial','sans-serif';">5 **Use suitable methods of research to find the names of plants with blue flowers. How many can you find?