exam q

Question 1

Explain why glycogen makes a good storage molecule.

Answer 1

insoluble ;
does not , change / affect , water potential / Ψ , of cell ;
can be , broken down / hydrolysed / built up ,
quickly / easily ;

lots of branches for enzymes to attach ;
compact ;
(therefore) high energy content for mass / energy dense

Question 2

colorimetry
a colorimeter is a piece of equipment used to quantitatively measure the transmission and absorbance of light by a coloured solution
the more concentrated the solution is, the more light it will absorb and the less light it will transmit
explain how to carry out a investigation to determine the concentration of a solution of glucose:

Answer 2

1) first a filter is placed on the colorimeter (red filter)
2)the colorimeter is callibrated using distilled water
3) benedicts test us performed on the solutions of known concentrations of glucose.
4)the solutions are then filtered to remove the red precipitate.
5) the percentage transmission of each of the solutions of glucose is measured using a colorimeter.
6) a callibration curve is drawn using the results
steps 3 to 6 are repeated using an unknown concentration of glucose