monomers, polymers + carbohydrates Flashcards
define monomers. give examples.
- smaller units that join together to form larger molecules
-monosaccharides (glucose, fructose + galactose)
-amino acids
-nucleotides
define polymer. give examples.
- molecules formed when many monomers join together.
-polysaccharides
-proteins
-DNA/RNA
what happens in a condensation reaction?
- a reaction where 2 compounds join together, with a formation of new chemical bond + a water molecule released when bond formed.
what happens in a hydrolysis reaction?
- a water molecule is used to break a chemical bond between 2 molecules.
name the 3 hexose monosaccharides .
- glucose
- fructose
- galactose
all have molecular formula C6H12O6
define what is meant by carbohydrates + how is it formed?
- made up of carbon, hydrogen and oxygen only.
- long chains of sugar molecules (poly) formed from lots individual sugar molecules (monosaccharides) joining together.
name the type of bond formed when monosaccharides react.
- (1,4 or 1,6) glycosidic bond.
- 2 monomers = 1 chemical bond = disaccharide
- multiple monomers = many chemical bonds = polysaccharide
explain the difference between alpha-glucose and beta-glucose.
- the hydrogen atom in alpha is above the hydroxyl group but the hydrogen atom is below the hydroxyl for beta
- glucose is hexose sugar which exists in “alpha” and “beta”
- position of hydrogen and hydroxyl group on the right hand carbon differs .
name 3 disaccharides. describe how they form.
condensation reaction forms glycosidic bond between 2 monosaccharides .
- maltose: glucose + glucose.
- sucrose: glucose + fructose.
- lactose: glucose + galactose
all have molecular formula: C12H22O11
what are the 2 diff forms that exist in starch?
- amylose + amylopectin.
describe the structure + function of amylose (starch).
- amylose = unbranded spiralling chains of a-glucose molecules .
- angle of glycolic bond gives coiled structure means its compact so lots amylose packed into cell /storage .
- (1,4 glycosidic bond) - helix with intermolecular H-bonds = compact.
describe the structure and function of amylopectin (starch) .
- branched chains of a-glucose molecules -> branches high surface area .
- side branches allow enzymes that break down molecule to her at glycosidic bonds quick = glucose released quick for respiration = (1,4 + 1,6) glycosidic bonds)
- many terminal ends - hydrolysis into glucose.
what are the features of starch
- storage polymer of a- glucose in plant cells
- insoluble = no osmotic effect on cells
- large = does not diffuse out of cells
describe the structure and functions of glycogen.
- main storage polysaccharide of a- glucose in animal cells (but also found in plant cells,)
- 1,4 + 1,6 glycosidic bonds
- branched = many terminal ends for hydrolysis
- insoluble = no osmotic effect + does not diffuse out of cells
- compact —> more stored in a cell .
describe the structure and functions of cellulose.
- long unbranded chains of b-glucose - multiple chains linked together by hydrogen bringing to form strong structures called microfibrils. =
strong micro in cell wall help give plant shape/structural support - rigidity to plant cell walls (prevent bursting under turgor pressure)
- 1,4 glycosidic bonds
- alternate glucose molecules rotated 180•
- H-bond cross links between parallel strands form microfibrils - high tensile strength .
