Carbohydrates Flashcards Preview

Biology A Level > Carbohydrates > Flashcards

Flashcards in Carbohydrates Deck (13):
1

Carbohydrates

A group of molecules containing C, H, O

2

What about monosaccharides make them good sources of energy?

Large number of carbon-hydrogen bonds

3

Maltose
Lactose
Sucrose

2 α-glucose
α + β
α + fructose

4

Condensation reaction removes water from…

2 hydroxyl groups (-OH)

5

Why are polysaccharides good stores of energy?

Less soluble because large + parts that could H bond are hidden

Chains branched so easily snipped off by hydrolysis when energy required

Branched so compact and don't take up space

6

Cellulose properties/structure

Tough
Fibrous
Insoluble
long chains + straight

7

What prevents cellulose chains from spiralling?

Bonding

Every other β-glucose rotated

β 1-4 glycosidic bond

H bonds between molecules/chains give strength

8

Cell wall from…

Macrofibrils from microfibrils from
cellulose chains

9

Cell wall structure

Macrofibrils in all directions, criss-cross walls

Space between macrofibrils make wall permeable to water/mineral ions

10

Cell wall function

Prevents cells bursting when turgid

Difficult to digest

Support plant like skeleton (turgid cells press against each other)

Protect cell membrane

11

What prevents cells from bursting when turgid?

High tensile strength

From glycosidic and hydrogen bonds

12

Bacterial cell wall made from

Peptidoglycan

Long polysaccharide chains in parallel

Short peptide chains cross-link

13

glycosidic bond

bond formed between 2 monosaccharides by a condensation reaction