Lecture 4 Flashcards
all living things are made up of which classes of biological molecules?
- carbohydrates
- proteins
- nucleic acids
- lipids
describe a monomer
a single biomolecule
describe a macromolecule
a large biomolecule made of smaller subunits that may or may not be identical. don’t have to be attached end to end.
describe a polymer.
long molecule made up of several similar or indentical subunits (monomers)
which biomelecules form polymers
carbohydrates
proteins
nucleic acids
how do two or more biomolecules form a polymer
dehydration synthesis.
- short polymer looses an H. unlinked monomer looses an OH. this forms water.
- a bond forms between the short polymer and the unlinked monomer.
How do you break down a polymer into monomers
hydrolysis
adds a water molecule, breaking a bond.
1 water = break 1 bond.
what is the function of carbohydrates?
energy source OR building material
what are the monomers of carbohydrates called?
monosaccharides
includes sugars
monosaccharides function
major fuel for cells and as a raw material for building molecules and as a raw material for building larger organic molecules.
what is the formula/ration of monosaccharides?
CH2O
1 carbon: 2 H: 1 O
What shape do the molecules of monosaccharides have?
drawn as a linear skeleton.
In aqueous solutions they form rings
what are the types of monosaccharides?
alpha glucose and beta glucose
describe alpha glucose structure
OH on the right (carbon 1) points down. matches the left side (carbon 4)
describe beta glucose structure.
OH on right (carbon 1) points up. opposite the the left side (carbon 4)
describe disaccharides
forms when a dehydration reaction joins two monosaccharides.
the bond between them is called a glycosidic linkage
what is the bond between monosaccharides caleed
glycosidic linkages
what are long chains of linked monosaccharides called?
polysaccharides
what is the formula for polysacharrides
a factor of CH2O
what are polysaccharides
long chains of linked monosaccharides
what are the function of polysaccharides?
energy storage OR structural support
describe the energy strorage function of polysaccharides
- storage polysaccharides in plants are called starches (amylose and amylopectin)
- storage in polysaccharide in animals and fungi is called glycogen
- all made of ALPHA GLUCOSE
describe the structural support function of polysaccharides
- structural polysaccharide in plants is called cellulose
- structural polysaccharide in fungi is called chitin
- all made of BETA GLUCOSE
what happens when plants produce more alpha glucose (by photosynthesis) than they can use?
they store the excess in the form of starch
what is a starch polymer
formed by alpha glucose monomers linked through glycosidic bonds
Name the types of starch
amylose
amylopectin
describe amylose
starch.
linear, unbranched, helical polymer
describe amylopectin
starch
branched polymer
what happens when fungi and animals absorb/ingest more alpha glucose than they can use?
they store some excess in the form of glycogen
what is a glycigen polymer formed of
alpha glucose monomers
what is a major component of the tough wall of plant cells
cellulose
what is cellulose
i a major component of the tough wall of plant cells
- polymer of glucose, different glycosidic linkages
- difference is because it is made of BETA GLUCOSE
describe cellulose structure
unbranched. long strands layered and linkedd by H-bonds.
how does cellulose pass through the digestive tract? why?
as insoluble fiber
bc enzymes that hydrolyze alpha linkages in starch cannot hydrolyze beta linkages in cellulose
- some microbiomes have enzymes that digest cellulose
- herbivores have symbiotic relationships with these microbes
describe structural support in fungi and animals.
chitin, a structural polysaccharide, is found in the exoskeleton of arthropods (insects and crustaceans) and fungal cell walls
describe structure on chitin molecule
beta glucose with a NHCOCH3 attached to carbon 2
