Phototropism And Location In Brassica Narinosa Lab Report
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Phototropism and Location in Brassica narinosa
Background
Phototropism is the tendency for a plant to react to the light in its surrounding environment. In plant shoots, this effect is created by the synthesis and transport of Auxin, a hormone that stimulates the growth of cells. Photoreceptors called phototropins sense certain wavelengths of light, and they cause the auxin to move away from the lit side of the plant. The auxin causes the cells on the dark side of the cell to grow larger than the lit side, causing the shoot to bend towards the light source. This adaptation allows plants to optimize the amount of light that they receive. Experiments done by Charles Darwin have shown the tips of coleoptiles to be especially photosensitive.
Aim
The aim of this lab is to explore the roles of different locations on the plant Brassica narinosa , commonly known as tatsoi, in the plant’s overall photosensitivity and phototropic tendency. Research Question
What is the relative importance of the leaves, apical meristem, and stem of Brassica narinosa in phototropic reactions?
Prediction
The leaves and the apical meristem of the plant will both play a role in phototropism, and the stem will not. The plants will be exposed to a light source coming from an angle, and the extent of each plants phototropic response will be measured by their curvature. The plants without leaves will have fewer photoreceptors to react to the angled light source, hence will be less phototropic. The plants