Download Chapter 3: Molecules of Life The molecules of life contain a high

Chapter 3: Molecules of Life
The molecules of life contain a high proportion of ____________________:
____________________, ____________________, ____________________,
____________________
Molecules that have primarily hydrogen and carbon atoms are said to be
____________________
Carbon’s importance to life arises from its versatile ______________________________
Carbon has ______________________________
Many organic molecules have a backbone: _____________________________________
____________________: consists only of carbon and hydrogen atoms
____________________: an atom (other than hydrogen) or small molecular
group bonded to a carbon of an organic compound; imparts a specific chemical
property
____________________: subunits of larger molecules (simple sugars, fatty acids, amino
acids, and nucleotides)
____________________: consist of multiple monomers (complex carbohydrates, lipids,
proteins, RNA / DNA)
Cells build ____________________ from ____________________, and break down
____________________ to release____________________; these processes of
molecular change are called ________________________________________
____________________: chemical reaction in which an enzyme builds a large
molecule from smaller subunits; water is formed during condensation
____________________: chemical reaction in which an enzyme uses water to
break a molecule into smaller subunits
____________________: all enzyme-mediated chemical reactions by which cells acquire
and use energy
____________________: organic molecule that speeds up a reaction without
being changed by it
____________________: organic compound that consist of carbon, hydrogen, and
oxygen in a 1:2:1 ratio
Three main types of carbohydrates in living systems: _____________________________,
______________________________, ______________________________
____________________ (one sugar) are the simplest type of carbohydrates
Common monosaccharides have a backbone of ___________________________
________________________________________
Six-carbon monosaccharides: ____________________, ____________________,
____________________
Five-carbon monosaccharides: ____________________, components of the
nucleotide monomers of DNA and RNA
Cells use monosaccharides for ______________________________; breaking the
bonds of sugars releases energy that can be harnessed to power other cellular
processes
Monosaccharides are also used as precursors for other molecules and structural
materials to build larger molecules
______________________________are short chains of covalently bonded
monosaccharides
____________________ consist of two monosaccharide monomers
Examples: ____________________: composed of glucose + galactose
____________________: composed of glucose + fructose
____________________: composed of galactose + fructose
______________________________: chains of hundreds or thousands of
monosaccharide monomers
____________________: main structural component of plants; tough and
insoluble; composed of chains of glucose monomers stretched side by side,
________________________________________
____________________: main energy reserve in plants; stored roots,
stems, leaves, seeds, and fruits; composed of a series of glucose monomers
that form a chain that coils up, ______________________________
____________________: main energy reserve in animals; very abundant
in muscle and liver cells; ______________________________
____________________: fatty, oily, or waxy organic compounds
Many lipids incorporate ______________________________: consist of a long
hydrophobic hydrocarbon tail with a hydrophilic carboxyl group head
__________________________________________________have only
single bonds linking the carbons in their tails; they are flexible and wiggle
freely
__________________________________________________have some
double bonds linking the carbons in their tails; their flexibility is limited
____________________: lipid that consists of a glycerol molecule with one, two, or
three fatty acid tails
______________________________: a fat with three fatty acid tails
______________________________: triglycerides with saturated fatty
acid tails; solid at room temperature
______________________________: triglycerides with unsaturated fatty
acid tails; liquid at room temperature
____________________: main component of cell membranes; contains __________
__________________________________________________and
__________________________________________________
In a cell membrane, phospholipids are arranged in two layers called a
______________________________
One layer of ______________________________are dissolved in
________________________________________
Other layer of ______________________________are dissolved in the
________________________________________
______________________________are sandwiched between the
hydrophilic heads
____________________: complex, varying mixture of lipids with long fatty acid tails
bonded to alcohols or carbon rings
Molecules pack tightly, so waxes are ___________________________________
________________________________________
Plants secrete waxes to ____________________________________________and
keep out parasites and other pests
Other types of waxes ____________________, ____________________, and
____________________ skin and hair
____________________: lipids with no tails; contain a rigid backbone that consists of
twenty carbon atoms arranged in a characteristic ______________________________
____________________
______________________________attached to the rings define the type of
steroid
Examples: estrogen and testosterone; both dictates many sex characteristics
____________________: large biological molecules, or macromolecules, consisting of
one or more long chains of amino acid residues
Cells can make thousands of different proteins from only
______________________________of monomers called amino acids
An ______________________________contains: an amine group (—NH2), a
carboxyl group (—COOH, the acid), and a side chain called an “R group”;
defines the kind of amino acid
The covalent bond that links amino acids in a protein is called a ____________________
A short chain of amino acids is called a ____________________
As the chain lengthens, it becomes a ____________________
Proteins consist of polypeptides that are hundreds or even thousands of amino
acids long
Proteins function in ____________________, ____________________, and
_______________________________________ (example: enzymes)
A protein’s biological activity arises from and depends on its ____________________
______________________________: linear series of amino acids; defines the
type of protein
____________________: polypeptide chain that forms twists and folds
______________________________: nonadjacent regions of protein adjoin to
create compact domains
______________________________: two or more polypeptide chains that are
closely associated or covalently bonded together
Enzymes often attach sugars to proteins (____________________) or lipids to proteins
(____________________)
Heat, some salts, shifts in pH, or detergents can denature (unravel) a protein by breaking
______________________________
____________________ causes a protein to lose its function
______________________________: chains of nucleotides in which the sugar of one
nucleotide is bonded to the phosphate group of the next
____________________: consists of a sugar with a five carbon ring bonded to a
nitrogen containing base and one, two, or three phosphate groups
Example: ATP (adenosine triphosphate); an energy carrier in cells
________________________________________: single-stranded chain of nucleotides;
important for protein synthesis
________________________________________: consists of two chains of nucleotides
twisted into a double helix; holds information to build a new cell