BIOLOGICAL MOLECULES PMT Qs

UNFINISHED, GOT: monomers and polymers, water

Galacto-oligosaccharides (GOS) are polymers of galactose.

Explain why GOS are described as polysaccharides [2]

1. galactose is a monosaccharide/monomer

2. (Polysaccharide is) carbohydrate polymer

3. several monosaccharides/monomers/galactose joined by condensation reactions OR by glycosidic bonds

Give two differences between GOS (polymer of galactose) and lactose [2]

1. lactose contains (alpha) glucose, GOS does not

2. Lactose is a disaccharide and GOS is a polysaccharide

3. lactose has one glycosidic bond and GOS has many/more than one glycosidic bonds

Explain why amylase produced in the human digestive system does not digest GOS (polymer of galactose) [2]

1. active site (only) complementary to starch

2. due to tertiary structure

(GOS is a polymer of galactose)

[3]

1. provides galactose/sugar

2. bacteria uses galactose/sugar for respiration

3. bacteria uses galactose/sugar for binary fission

Explain how this conclusion is supported by the experiment in the figure [3]

1. evaporation/transpiration from the porous pot

2. tension created moves water upwards

3. cohesion maintains the column of water OR cohesion is due to hydrogen bonds between water molecules