Date | November 2018 | Marks available | 1 | Reference code | 18N.3.SL.TZ0.9 |
Level | Standard level | Paper | Paper 3 | Time zone | TZ0 / no time zone |
Command term | Outline | Question number | 9 | Adapted from | N/A |
Question
The starch found in potato tubers (Solanum tuberosum) is normally a mixture of 80 % amylopectin and 20 % amylose. The Amflora potato is genetically modified to alter this ratio. The modified potato is not suitable for human consumption but is grown for industrial uses.
Compare and contrast amylose with amylopectin.
Outline how the composition of starch differs in the Amflora potato compared to a normal potato.
State one industrial use of the Amflora potato.
Suggest one reason for concerns about growing GM crop varieties such as the Amflora potato on farms.
Markscheme
a. amylopectin is «more» branched/has 1,6 bonds
OR
amylopectin is less soluble in water ✔
b. both made up of glucose
OR
both are polysaccharides
OR
both are helical in shape
OR
both contain glycosidic bonds ✔
Accept converse statements
amflora contains «almost» no amylose/«almost» all amylopectin ✔
used in the paper/glue/textile/concrete industry ✔
a. encourages monocultures/reducing biodiversity ✔
b. may reduce natural resistance to pests/disease ✔
c. may cross-pollinate with non-GM crops ✔
d. disruption of practices of farming/agricultural land not being used for food production ✔
e. crop-to-crop gene flow ✔