ch. 3 biological macromolecules Flashcards
what are macromolecules?
usually larger molecules constructed from smaller subunits
what is a monomer?
a single subunit
what is a polymer?
many units
what are anabolic reactions?
they take simpler molecules and build bigger ones; usually requires energy; “build things up”
what are catabolic reactions?
They break down complex molecules into simpler ones; usually release energy
what is dehydration synthesis?
the formation of bonds by production of water (opposite of hydrolysis) (requires OH- and H+)
what is hydrolysis?
the breaking of bonds by the addition of water (opposite of dehydration synthesis) (complex molecules broken down)
what are carbohydrates?
sugars; structural and energy storage
what are lipids?
fats, oils, cell membranes, energy storage
what are proteins?
coded for by DNA, carry out most cellular functions
what are nucleic acids?
dna and rna; code for proteins
what is the ratio of C:H:O in carbohydrates?
1:2:1
if it ends in -one, it is a ____
sugar
what are CHOs good for?
energy storage and transfer
what is glucose?
monosaccharides; important for intracellular energy storage and respiration
what is fructose?
a structural isomer of glucose
what is galactose?
a structural stereoisomer of glucose
sugars are typically in what structure?
a ring structure
sucrose =
glucose + fructose
what are disaccharides?
2 monosaccharides linked together by dehydration synthesis
What are disaccharides used for?
sugar transport or energy storage (esp. in plants)
what are sucrose, lactose, and maltose examples of?
disaccharides
what are polysaccharides?
long polymers of sugars
what are polysaccharides used for?
long term energy storage
what is the common polysaccharide found in most plants?
starch
what is the common polysaccharide found in most animals?
glycogen
what polysaccharide is used in some plants for structural support?
cellulose
what polysaccharide is used in some animals for structural support?
chitin
humans store 20 to 30 min worth of energy from what?
glycogen
What polysaccharide do we need to first use up in order to start losing weight?
glycogen
are lipids soluble or insoluble in water? why?
insoluble because they lack charge polarity
what causes lipids to be hydrophobic?
a high proportion of non-polar C-H bonds
What are the two main types of lipids?
fats and phospholipids
what are triglycerides composed of?
1 glycerol and 3 fatty acids
what are fatty acids?
long hydrocarbon chains that can be saturated or unsaturated
What vitamins are lipid soluble?
A, D, E, and K
What does it mean when a lipid is saturated?
it is saturated with hydrogen
what makes a lipid unsaturated?
two hydrogens are missing and there is a double bond between two carbons
what can happen to an unsaturated fat to make it saturated?
if the double bond between carbons is broken
What is the function of triglycerides?
long-term energy storage
What stores twice as much energy as CHOs?
triglycerides
what are typically characteristics of animal fats at room temperature?
saturated and solid
what are typically characteristics of plant fats at room temperature?
unsaturated and liquid
what makes a lipid more liquid?
more double bonds
when a lipid is more saturated, what effect does that have?
the lipid becomes more solid
what does an unsaturated, C=C bind do to a fatty acid chain?
causes a kink in the chain
what are phospholipids made of?
1 glycerol, 2 fatty acids, and a phosphate group
when do you produce cortisol?
when stressed
what are proteins?
polymers of amino acids
what are the functions of proteins?
enzymes, defense, transport, support, motion, regulation, cell metabolism, storage
what is the structure of an amino acid?
central carbon atom surrounded by an amino group, carbonyl group, single hydrogen, and a variable “R” group
how many different amino acids are there?
20
in what ways can “R” groups differ?
polar, non-polar, positive, negative, charged, aromatic, special function, etc.
what dictates the chemical properties of an amino acid?
structure of the R group
how are amino acids linked?
dehydration synthesis (creates a peptide bond between them)
what is a peptide?
a string of amino acids
what is a primary structure?
sequence of amino acids
what is a secondary structure?
interactions of groups in the peptide backbone (dictated by primary structure)
what are alpha helixes and beta pleated sheets?
motifs; secondary structures
what are tertiary structures?
folded shape of a polypeptide chain
in what structure do proteins typically find their functions?
tertiary
what are quaternary structures?
interactions between polypeptide subunits (tertiary structures that did not already find their purpose)
what are motifs?
common elements of secondary structures seen in many polypeptides
what are domains?
the functional regions of a polypeptide
what happens when a protein denatures?
the shape of the protein changes, usually causing loss of function (may involve complete unfolding; caused by things like pH and temp)
