Carbohydrates

Question 1

Type of reactions for polymer

Answer 1

Condensation- removal of water to form large molecules
Hydrolysis- addition of water break down large molecules

Question 2

Monosaccharides

Answer 2

(CH2O)n
glucose,fructose,galactose
glucose- a-glucose
b-glucose
all are reducing sugars

Question 3

Test for reducing sugars

Answer 3

2cm^3 of liquid solution
equal volume of Benedict solution
boil
+ result=brown colour solution

Question 4

Disaccharides

Answer 4

Glycosidic bonds
Most are non-reducing sugars
same as reducing test
if - add HCL and boil
add sodium hydrogen carbonate to neutralize
re-test
if positive reducing sugar from non-reducing

Question 5

Polysaccharides

Starch

Answer 5

large amounts in seed and storage
major energy source of many diets
Made from chains of a-glucose
can be branched and unbranched
unbranched chain is tightly wound
Main function is energy storage

Question 6

structure suited for role due to(starch)

Answer 6

• insoluble( does not affect water potential, water is not drawn by osmosis)
• Large and insoluble(does not diffuse out pf cell)
• compact(stored in a small space)
• when hydrolysed become a-glucose,easily transported and readily used in respiration
• branched ends aid enzymes to release glucose molecules rapidly

Question 7

Glycogen

Answer 7

• found in animals and bacteria
  -similar to starch but with shorter chains and more branched
  -stored as small granules in muscles
  used as a storage

Question 8

structure suitable to role due to(glycogen)

Answer 8

Insoluble(does not draw water in through osmosis)
does not diffuse out of cells
compact
more highly branched(rapidly break down of a-glucose)

Question 9

Cellulose

Answer 9

made form b-glucose
straight, unbranched chains
run parallel to one another allowing H bonds to form
the weak strength of H bonds, the high amount of bonds gives strength
grouped together to form microfibrils
major component of cell wall
prevents cell from bursting
exerts pressure to stop influx of water
maintaining stems and leaves in turgid state
it is a structural component and gives support and rigidity

Question 10

structure suitable to role due to(cellulose)

Answer 10

form long straight unbranched chains
chains run parallel to each otherand linked by H bonds which add collective strength
chains form microfibrils and then fibres which adds to strength.