hey, just a quick question. how does betalain enter the vacuole?
biology betalain Watch
- Thread Starter
- 07-01-2015 20:04
- 08-01-2015 06:31
Um I found this answer, do check if it helps
In Beetroot cells, the vacuoles also contain pigments called, ‘betalain’ which are red pigments, whose function is not entirely clear. They replace pigments called ‘anthocyanins’ in higher plant species such as the beetroot. When the beetroot cylinders are heated, it is this pigment that leaks out of the cell giving an indication of the cell’s permeability in relation to temperature, as measured by the colorimeter. In the experiment, at low temperatures of below 40 C, the cell membrane is intact and effectively carries out its task of controlling the entry and exit of molecules into and out of the cell. On the graph, this is shown by the small gradient of the line below 40 C. As the temperature increase however, the proteins in the membrane begun to denature and no longer function appropriately. The protein is held together by hydrogen bonds and disulphide bridges between the amino acids. Excess heat causes an increase in the kinetic energy given to these molecules making them vibrate and eventually breaking the bonds. The rise in temperature also causes the water within the membrane to expand putting pressure on the membrane from within. As a result, the lipid component of the membrane liquefies. The denaturation of the proteins and liquefaction of the phospholipid bilayer greatly increases the permeability of the cell membrane. A similar effect on the tonoplast of the vacuole causes a leakage of the ‘betalain’ pigments out of the vacuole and eventually out of the cell itself through the cell membrane into the surrounding water used in the experiment. One explanation for the movement of betalain pigments out of the cell is diffusion. The higher concentration of betalain pigments inside the cell means that they will diffuse into the surrounding water where their concentration is low. The kinetic energy generated by heat will also facilitate this process as the betalain pigments will have a higher energy, making them move faster.