SBI4U: Biochemistry

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isotonic
when the concentrations of ECF (extracellular fluid) are the same as the ICF (intracellular fluid)
hypotonic
there is more water than solute in the environment
hypertonic
there is more solute than water in the environment
ATP
adenosine triphosphate
carbohydrates, lipids, proteins, and nucleic acids
4 compounds of life required by our cells in order to complete the functions of life
oxidation
loss of an electron: substance losing the electron is oxidized and called the reducing agent
reduction
gain of an electron- substance gaining the electron is reduced or called the oxidizing agent
dehydration synthesis
a reaction where a molecule of water is removed and small molecules are assembled into larger ones (requires energy)
hydrolysis
a reaction where a molecule of water is added, breaking macromolecules into micromolecules (produces energy)
functional group
a specific arrangement of atoms that take part in a chemical reaction (the reactive part). Everything else is considered ‘boring’ and is called an R group.
hydroxyl
have an OH group, general formula R-OH
ketones
double bonded O to two or more other carbons
carboxyl
carbonyl group and a hydroxyl group
esters
derivatives of carboxylic acids in which the OH of the carboxyl group is replaced by an OR from an alcohol (an O sandwiched between two carbons)
amino
organic compound with an amin- group (NH2)
sulfhydryl
sulfur bonded to a hydrogen, R-SH
phosphate
contains P, common to many biological compounds
monomers
small, similar molecular units
polymers
longs chains of monomers; can be a straight chain or branched
carbohydrates
an organic compound made up of sugar molecules; used as an energy source, can be stored within minutes for later use
glycogen
storage form in animals
starch
storage form in plants
sugars
contain C, H and O in a 1:2:1 ratio; most molecules in nature have a ring shape
monosaccharides
simple sugars containing just one sugar unit (e.g glucose, fructose, galactose, 3 isomers)
disaccharides
using a dehydration synthesis reaction, cells put together 2 monosaccharides to form this (e.g. sucrose, lactose, maltose)
polysaccharides
long polymer chains made up of simple sugar monomers (e.g. starch, glycogen, cellulose), held together by glycosidic bonds (alpha/beta)
cellulose
a building material in plants, protect cells; stiffens plant so it doesn’t fall over, made up glucose monomers, multiple chains form H bonds
lipids
non-polar, hydrophobic biological molecules
functions of lipids
store energy, form cell membranes, make hormones, insulate and protect organs
fatty acids
single hydrocarbon chain with a carboxyl functional group
saturated triglycerides
tend to be more solid, obtained from animals (e.g. butter and lard), difficult to break down, linked with single bonds
unsaturated triglycerides
liquid at room temperature, derived from plants (e.g. olive oil), easier to break down, linked with double bonds
fats
lipids made of two molecules (fatty acid, glycerol)
phospholipids
phosphate containing lipids; primary lipids of cell membranes. They have a hydrophilic head and a hydrophobic tail
steroids
large lipids (consist of four carbon rings) functional groups attached to the rings distinguish one from another
cholesterol
steroid that is an important component of the plasma membrane; diet rich in it can lead to atherosclerosis
waxes
large lipid molecules made of long fatty acid chains linked to alcohols or carbon rings
proteins
polymers that have many subunits a into three dimensional structures that determine its functions
amino acids
the building blocks of proteins
peptide bonds
link amino acids together via dehydration synthesis, creating polypeptides
primary structure
linear sequence of amino acids, changing one amino acid will change protein’s structure, therefore its function
secondary structure
hydrogen bonding causes them to spiral/coil, form either beta pleated sheets or an alpha helix, gives protein strength
tertiary structure
hydrophobic interactions causes protein to fold
quaternary structure
2 or more polypeptides come together forming complexed structures, create globular shapes
denaturation
(the breakdown of a polypeptide) can be caused by a change in temperature, change in pH, change in ionic concentration, exposure to chemical agents
enzyme
a protein that acts as a catalyst (speeds up the rate of the reaction without changing the products)
enzyme inhibitor
decrease enzyme activity
competitive inhibitor
similar to the enzyme substrate, enter the active site preventing the normal substrate from entering, therefore blocking normal binding
non-competitive inhibitor
attach to enzyme changing its shape therefore its function
3 main parts of a nucleotide
5 carbon sugar (deoxyribose or ribose), nitrogenous base, phosphate group
purine
double ring structure (adenine and guanine)
pyrimidine
single ring structure (thymine, uracil, cytosine)
polynucleotide
chain of nucleotides, curves to form a double helix
Categories: Biochemistry