polysaccharides

Question 1

how are polysaccharides formed

Answer 1

many monosaccharides units joined by condensation reactions that form glycosidic bonds

Question 2

oligosaccharides

Answer 2

molecules with 3-10 sugar units

Question 3

true polysaccharides

Answer 3

molecules with more than 11 sugar units or 11

Question 4

why do polysaccharides make good storage molecules

Answer 4

-they can form very compact molecules so large numbers can be stored in a cell
-glycosidic bonds broken down easily rapid release of energy
-not soluble in water so dont disturb osmotic potential

Question 5

how is a glycosidic bond broken

Answer 5

by a hydrolisis reaction

Question 6

what is hydrolisis

Answer 6

the opposite of condensation where water is added

Question 7

what happens when polysaccharides break down

Answer 7

they turn into smaller and shorter chains and eventually a simple sugar aka a monosaccharide

Question 8

where does hydrolisis reaction take place

Answer 8

in the gut
-muscle and liver cells when carbs stored are broken down to release sugars for use in cellular respiration

Question 9

what carbon bond is hydrolisis of alpha glucose and alpha glucose

Answer 9

1-4 bond

Question 10

why is starch important in plants

Answer 10

sugars produced by photosynthesis rapidly converted to starch which is insoluble and compact

Question 11

what monosaccharide is starch made of

Answer 11

alpha glucose

Question 12

what 2 mixtures is starch made of

Answer 12

amylose
amylopectin

Question 13

what is amylose

Answer 13

a branched polymer made of between 200 to 5000 glucose molecules

Question 14

what happens to amylose as the chain lengthens

Answer 14

it spirals making it more compact for storage

Question 15

what is amylopectin

Answer 15

branched polymer of glucose molecules

Question 16

whats special about amylopectin

Answer 16

branching chains have terminal glucose molecules which can be broken of easily for quick energy

Question 17

what carbon bond does amylose have

Answer 17

1-4 pure alpha glucose bonds which are why they are unbranched

Question 18

what carbon bonds does amylopectin have

Answer 18

1-4 but a few 1-6 bonds which is why the molecule is branching which change the properties of the molecule

Question 19

why are starchy foods good for sports and athletes

Answer 19

starch has a combination of straight chained and branched chain molecules
amylopectin releases glucose rapidly and amylose releases it slowly to keep you going longer

Question 20

what energy store of carbs is found in animals

Answer 20

glycogen

Question 21

what is glycogen an important storage molecule in (2)

Answer 21

fungi and animals

Question 22

glycogens chemical structure

Answer 22

similar to amylopectin molecules and made up of lots of alpha glucose units

Question 23

physical structure of glycogen

Answer 23

its has more 1-6 bonds giving it many side branches so it can be broken down rapidly
-this makes it an ideal source for glucose in active tissues with high cellular respiration rates

Question 24

starch in plants

Answer 24

main source of energy

Question 25

what are plant cell walls made of

Answer 25

insoluble cellulose

Question 26

structure of cellulose

Answer 26

long chains of glucose joined by glycosidic bonds

Question 27

monosaccharides in cellulose

Answer 27

they are beta glucose units joined by 1-4 glycosidic bonds where one of the monomer is inverted
-linking of beta glucose molecules means OH group sticks out on both sides of the molecule

Question 28

what is cross linking

Answer 28

linking of beta glucose means OH groups stick out on either side
-hydrogen bonds form between partially positive charged hydrogen atoms of hydroxyl groups and partially negative charged oxygen atoms of other areas
holds neighouring chains closely together

Question 29

physical structure of cellulose

Answer 29

it doesnt branch and is a long chain straight molecule

Question 30

why dont animals have cellulose

Answer 30

because they dont have the enzymes to break down the 1-4 beta bonds and have starch instead

Question 31

what do cows and sheep have that allows them to digest cellulose

Answer 31

they have fungi and bacteria that make digestive enzymes which break down cellulose

Question 32

effects of cross linking

Answer 32

high tensile strength

Question 33

calcium pectate

Answer 33

found in middle lamella
cell walls together