Carbohydrates and Lipids Flashcards
what are the 4 most important molecules of life?
carbohydrates
lipids
proteins
nucleic acids
what are macromolecules?
polymers built from monomers
how do macromolecules possess unique properties?
the arrangement of their atoms
what are polymers?
long molecules consisting of monomers linked by covalent bonds
how are polymers synthesized?
enzymes - monomers connect through a dehydration reaction (polymerisation)
what breaks down the bonds between monomers?
hydrolysis
what gives polymers diversity?
the different combos of monomers and lengths of polymers
what do carbohydrates include?
sugars and polymers of sugars
what are monosaccharides?
simple sugar monomers from which complex carbohydrates can be built
what are disaccharides?
2 monosaccharides covalently joined by a glycosidic link
what are polysaccharides?
carbohydrate macromolecules
what is the pattern of monosaccharide formulae
multiples of C6H12O6 with a =O group and multiple hydroxyl groups
what differentiates a ketose or aldose sugar?
the location of the =O group
what shape do pentoses and hexoses typically take?
rings
what is the major role of monosaccharides?
major nutrients for living cells
what is the major role of polyssacharides?
storage or building material
what is an example of a disaccharide?
maltose used in brewing beer
what are the main characteristics of starch?
starch molecules are helical for efficient storage
starch molecules are branched
what are the main characteristics of cellulose?
cellulose is straight and never branched
in plant cell walls, parallel cellulose molecules held together via H-bonds are grouped into microfibrils like cables.
what is cotton made from ?
cellulose microfibrils
what are the most important biological lipids?
fats
phospholipids
steroids
t/f lipids are hydrophilic?
f - hydrophobic
what is a fat constructed from?
a glycerol and 3 fatty acid molecules
what is a fatty acid constructed from?
a long carbon skeleton and a carboxyl group
what is a more efficient energy storage - fat or polysaccharides?
fat
what are phospholipids made from
2 fatty acids attached to a glycerol and a negatively charged phosphate group
how do cell membranes form?
the hydrophilic head and hydrophobic tails form a phospholipid bilayer
what are steroids made of?
lipids with a carbon skeleton made up of 4 fused rings
what is cholesterol?
a steroid
a precursor for other steroids e.g. vertebrate sex hormones
how does diversity occur in steroids?
the different groups attached to the rings
