Chapter 1 - intro to biochemistry

biochemistry is the study of

molecules and chemical reactions of life

biochemistry uses principles and language of - to explain processes of living cells at the -

chemistry, molecular level

organic chemistry studies the reactions of

organic compounds in test tubes

biochemistry studies reactions in

living cells

enzymes in living cells increase reaction rates without violating the fundamental

reaction mechanisms of organic chemistry

Friedrich Wohler showed that there was no vital force when he synthesized

urea from inorganic ammonium cyanate

Eduard Buchner showed that extracts of yeast cells could catalyze fermentation of

glucose to EtOH and CO2

Emil Fisher proposed

lock-and-key theory

Avery, MacLeod and McCarty extracted DNA transformed a

non-toxic strain of S. pneumonia

James Watson and Francis Crick deduced 3D shape of DNA as

double helix

structure of helix suggested how DNA could replicate and transmit biological information encoded in

DNA to succeeding generations

central dogma: information flows from

DNA - RNA - protein

enzymes and nucleic acids are central to the

chemistry of life

some important techniques include

ultracentrifugation, chromatography, electrophoresis, radioactive tracers

six elements make up over 97 percent of biological matter

chops

carbon is much more abundant in living organisms than the

rest of the universe

water is also a major component of

cells

forming an ester linkage includes

an acid and an alcohol

forming phosphate anhydride includes

two phosphoric acids

biopolymers are macromolecules created by joining many smaller organic molecules,

monomers, via condensation/dehydration reaction

polymers have directionality, one end is always -

chemically different from the other

genetic information is stored in the

nucleotide sequences of nucleic acids

polynucleotides are composed of monomers called

nucleotides

there are two types of nucleotides,

deoxyribose nucleic acid and ribose nucleic acid

each nucleotide consists of

five carbon sugar, phosphate group, and nitrogenous base

each nitrogenous base is either a

purine or pyrimidine

ATP structure

adenine base linked to sugar via glycosidic bond, with three phosphoric groups

phosphoester linkage is between

POC

phosphoanhydride linkages is between POP

ATP is a building block of

nucleic acids and central energy carrier

nucleic acids are linear polymers of nucleotides linked by a -, a phosphate group linked to two adjacent nucleotides via -

3’ 5’ phosphodiester bridge, two phosphodiester bonds

the polynucleotide formed by this process has a directionality with a 5’ - group at one end and a 3’ - group at the other

phosphate, hydroxyl

nucleotides are only added to the free

3’ end of a polynucleotide

nucleotide sequences are conventionally written in the

5’ to 3’

between A and T, there are

two hydrogen bonds

between C and G, there are

three hydrogen bonds

DNA has high

fidelity replication

DNA stores information and has sequence specific

interactions with proteins

proteins are the most - of macromolecules

functionally and structurally diverse

protein functions also include:

structural, storage, transport, hormonal, receptors, contractile, defence, enzymes

proteins are polymers made of monomers called

amino acids

amino acids have a

hydrogen group, amino group, carboxyl group, and an R group

amino acids join together in - reactions to form -

condensation, peptide bonds

sequence of amino acids determines the folding of

linear polypeptides

many proteins are enzymes, containing a characteristic cleft that contains the

active site

excessive quantities of wrongly folded proteins collect in the form of uncontrolled piles of - (ex. -)

molecular rubbish, amyloidosis

mad cow disease is caused by -, which can’t be destroyed by -

prions, heat

prions are the only known infective agents that do not contain

genetic material

prions cause brains of victims to degenerate and become

porous

the infectious prion triggers a - in healthy prions, forcing them to adopt its -

domino effect, incorrectly folded form

carbohydrates consist of

monosaccharides and their polymers

all carbohydrates are

polyalcohols, and are polar and hydrophilic

carbohydrates are the direct product of

photosynthesis

carbohydrates are the most - of the biomolecules and serve as precursors to all other -

abundant, biomolecules

major functions of carbohydrates

storage structural, metabolic intermediates, components of other molecules, cell-signalling

aldosugars have a - carbonyl group

terminal

ketosugars have an - carbonyl group

internal

glucose is the most - hexose

abundant

sugar forms are designated

alpha or beta

alpha sugar means the hydroxyl group is - and beta sugar means the hydroxyl group is -

downward, upward

glucose is the manometrical structural unit of

dissacharides and polysaccharides

dissaccharides

maltose, lactose, sucrose

polysaccharides

cellulose, starch, glycogen

carbohydrates are residues joined by

glycosidic bonds

starch and glycogen consist of alpha-D-glucose units that are linked by

alpha 1,4 - glycosidic bonds

in starch and glycogen, occasionally -form, allowing for the formation of ,

alpha 1,6 - glycosidic bonds, side chains

cellulose is composed of repeating beta-D-glucose monomers linked by

beta 1,4-glycosidic bonds

different enzymes are required to break

alpha vs beta linkages

mammals cannot digest

cellulose

\- can be attached to proteins on the surface of a cell

oligosaccharides

oligosaccharides play an important role in

cell recognition and interactions

lipids are -, not polymers

aggregates

lipids are still regarded as macromolecules because of their -, importance in cellular structures, especially -, and are made by

high molecular weight, membranes, condensation reactions

lipids are

structurally diverse

all lipids are - in nature and - in water

hydrophobic, insoluble

all lipids are readily soluble in - solvents

non polar

lipids have relatively few polar groups, but some are -, having both polar and non polar regions

amphipathic

lipids store -, provide -, or specific biological functions such as -

energy, membrane structure, signal transmission

lipids are a major component of cell membranes because the - of lipid aggregate gives the membrane unique characteristics

insolubility and flexibility

fatty acids are building blocks of

several classes of lipids

fatty acids are described as long -, unbranched hydrocarbon chain with a -

amphipathic, carboxyl

fatty acids have a variable

number of carbons

saturated fatty acids do not have

double bonds

unsaturated fatty acids at least have one -, liquid at -

double bond, RT

triglycerides are made up of

glycerol and three fatty acids, linked by ester

the main function of triacylglycerols is

energy storage

some animals store triacylglycerols under the - as protection against cold

skin

phosphoglycerides are the predominant

phospholipids in most membranes

the basic components of phosphoglycerides is phosphatidic acid, which has

two hydrophobic fatty acids and a phosphate group attached to a glycerol

membrane phosphoglycerides have a - linked to the phosphate by an -

small hydrophilic head group, ester bond

phospholipid: the presence of both hydrophilic and hydrophobic regions makes this an

amphipathic molecule

hydrophilic portions face the -, hydrophobic portions face the -

aqueous environment, lipid-rich environment

the lipid bilayer acts as a barrier separating - or compartments from -

cells, environment

the lipid bilayer is impermeable to most

water-soluble compounds

the lipid bilayer is

flexible

steroids are derivatives of a - skeleton, which distinguishes them from other -

four-ringed hydrocarbon, four-ringed hydrocarbon

steroids are synthesized from

cholesterol

cholesterol is important in regulating

membrane fluidity

steroid hormones include

sex hormones, glucocorticoids, and mineralcorticoids

sex hormones include

estrogen, testosterone, and androgen