Essay On Gibberellin

Introduction: Gibberellin is a plant hormone that is involved in the production of amylase which is vital for the conversion of starch into maltose into glucose molecules required for the embryo to grow. It does this by “regulating the genes that are involved in the synthesis of amylase. In barley seeds, it has been shown that the application of gibberellin causes an increase in the transcription of mRNA coding for amylase”. 1(Jones, p.120)
Below is Diagram 1 showing the longitudinal section through a barley seed, outlining the process undertaken for the conversion of starch into maltose, by the action of seed embryo synthesis initiating germination, and the production of gibberellin. 2(Jones, p. 120).
Diagram 1:
Aim:

Gloves must be worn as well, especially on preparation of the Petri dishes as any skin contact with the agar immediately transfers micro bacteria and these bacteria may start to grow and contaminate the dish. Extreme care must also be taken whilst using the scalpel as they are incredibly sharp, as found from my preliminary work.
Method: 1) First make up 11 separate solutions in the 11 beakers, using the measuring cylinders and following Table 1 below. Label the beakers 1-11, in correspondence to the concentration of gibberellin in each. Add 3-4 barley seeds to each beaker and leave in a water bath overnight at a temperature of around 30 ̊C. From my preliminary work I realised that the seeds come in all different shapes and sizes so it is quite important to select seeds of a similar size and width to ensure as accurate as possible

(Jones, p.46-47) So the more gibberellin present, (i.e. the seeds that soaked overnight in the highest concentration of gibberellic acid solutions), should have produced the most amylase (the most enzymes). This means that with a greater number of enzymes there should be more starch broken down and therefore those seeds with the highest concentrations of gibberellin should have the greatest clear area around each half seed.
6) If the area around the seed is regular, a ruler can be used to measure the radius of the circle in mm. This can be used to calculate the area of the circle using the formula πr2. If the area around the seed is irregular, the acetate graph paper can be used to count the number of 1mm x 1mm squares around each half seed. From my preliminary work I found out that using 0.5mm x 0.5mm acetate meant that the squares were too small to calculate with the naked eye, and that the 1mm x 1mm acetate was suitable enough to