Lecture 1: Introduction to Biochemistry Flashcards
showed that urea, a substance of biological origin, could be be synthesized in the laboratory
Friedrich Wöhler
within the living thing
in vivo
happening outside the living organism
in vitro
urea could be synthesized from the inorganic compound
ammonium cyanate
turned his attention to fermentation in order to help the French wine
industry
French chemist Louis Pasteur
Pasteur recognized that wine could be spoiled by the accidental
introduction of ___ during the fermentation process
bacteria
___ cells alone posssess the ability to convert sugars in grapes to ethanol in wine
yeast
___ was introduced to prevent spoilage of wine by heating the beverage to kill the bacteria
Pasteurization
held that biological reactions took place only through the action of a mysterious “life force” rather than physical or chemical processes.
vitalism
vitalism dogma was shattered by two brothers ___ and __
Eduard and Hans Buchner
found that extracts from ____could carry out the entire process of
fermentation of sugar into ethanol.
dead yeast cells
Buchner brothers’ study lead to the biochemical analysis in ___
vitro (in glass)
biological
catalysts,
enzymes
showed that an enzyme from jack beans,
called ____, could be crystallized like any organic
compound and that it consisted entirely of protein
james B.
Sumner,,, urease
the discovery of ___ marked the downfall of vitalism
urease
control
synthesis of the enzymes involved
gene expression
a unit of hereditary information discovered by Gregor Mendel
gene
genes must be
found in ___
chromosomes
Nucleic acids had been recognized
as cellular constituents since their discovery in 1869 by ____
Friedrich
Miescher
the early 1900s nucleic acids were thought to be simple substances,
fit only for _____ in the cell. Most biochemists believed that
only _____ were sufficiently complex to carry genetic information.
structural roles’’’’ proteins
Experiments in the 1940s
and early 1950s proved conclusively that ____ is the primary bearer of genetic information
deoxyribonucleic acid
DNA
____ is also an informational molecule
ribonucleic
acid, RNA,
described the doublehelical
structure of DNA
James Watson and Francis Crick
Evolution of biochemistry summary
doctrine of vitalism > wohler’s synthesis of urea > discovery of fermentation > cell-free enzymatic reactions > elucidation of enzyme structure > existence of genes > discovery of DNA > DNA as a genetic material > DNA double helix > Central dogma of molecular biology > rise of biotechnology
the most abundant elements are called ___
1st tier elements
____, 1st tier elements, are important
to life because of their strong tendencies to form ___ bonds
C H O N ,,,, covalent
the ____ of carbon–carbon bonds and the possibility of
forming single, double, or triple bonds give carbon the versatility to be
part of an enormous diversity of chemical compounds
stability
___ of essential elements includes sulfur and phosphorus,
which form covalent bonds, and the ions Na+, K+, Mg2+,
Ca2+, and Cl-.
“second tier”
Second tier element includes ___
sulfur and phosphorus
Sulfur is a constituent of nearly all ____,
proteins
phosphorus
plays essential roles in ___ and the structure
of ___.
energy metabolism,,, nucleic acids
third- and fourth-tier elements are metals, some of which serve as
aids to the ____
catalysis of biochemical reactions
Many
biochemists believe that the earliest primitive systems, capable of self-replication
and some form of metabolism, were based on ____.
ribonucleic
acid (RNA)
___ are giant molecules made up of smaller
organic molecule subunits
Biological macromolecules
in living organisms there are ___ major
classes of macromolecules,
four
list the major classes of macromolecules
proteins, nucleic acids, carbohydrates, and lipids
if the DNA molecules in a single human cell
were stretched end to end, they would reach a length of about __
2 meters
These biopolymers are made by joining
together prefabricated units, called ____
monomers
Of the four classes of
macromolecules, ___ of them are biopolymers
three
list the biopolymers
proteins, nucleic acids,
and carbohydrates
true or false: lipids are not biopolymers
true
simple example is the carbohydrate
___, a major constituent of the cell walls of plants.
cellulose
Cellulose is a polymer made by joining thousands of molecules of
_____
glucose
Covalent links between glucose
units are formed by removing a water molecule between two adjoining
glucose molecules, ____
condensation
true or false: all chemical linkages in this molecule are identical
NAMED: ___
true;; glycosidic linkage
Because cellulose is a polymer
of a simple sugar, or saccharide, it is called a ___
polysaccharide
a type of polymer that is constructed from identical monomeric units is called a ____
homopolymer
many polysaccharides—and
all nucleic acids and proteins—are ____, a type of polymer
heteropolymers,
Nucleic acids are polymers made up of four
___
nucleotides
nucleic acids are also called ___
polynucleotides.
proteins are assembled from combinations of
20 different ____
amino acids.
Protein chains are called ___, a
term derived from the ____ that joins two amino acids
together.
polypeptides;; peptide
bond
list protein diverse biological functions and site an example
Structural- keratin and collagen Transport- hemoglobin Signalling- hormones, receptors Immunity- antibodies Catalysis- enzymes
___catalyzes
the joining of nucleotide molecules to synthesize RNA
RNA polymerase
nucleotides are connected by ____ bonds
phosphodiester bonds
true or false: lipids have low solubility in the aqueous
environment of the cell.
true
lipids function is to serve as the major ___ element
of the membranes that surround cells and partition them into
various compartments
structural
___ formerly called triglycerides, are esters
Triacylglycerols
Triacylglycerols are formed by condensation between the three hydroxyl groups of
__and three long-chain ___
glycerol ;;; fatty acids
Phospholipids are ____meaning that they have both hydrophobic
and hydrophilic functional groups
amphipathic
phospholipids have ____, cluster on the outside, in contact with the watery milieu.
polar head
