Mod 2 Topic 2 Flashcards
- biological medium here on Earth
- most abundant substance in living systems
- making up 70% or more of the weight of most organisms
water
Water has four emergent properties:
- Cohesion and Adhesion of Water Molecules
- Moderation of Temperature by Water
- Evaporative Cooling of Water
- Water as the Solvent of Life
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- are macromolecules that exist as polymers called polynucleotides
- they store, transmit, and help express hereditary information
nucleic acid
- a nucleotide is composed of three parts
a nitrogenous base, a five-carbon sugar, and one or more phosphate groups
- has one six-membered ring of carbon and nitrogen atoms
pyrimidine
members of
pyrimidine are
cytosine, thymine, and uracil
- are larger, with a six-membered ring fused to a five-membered ring
adenine, and guanine
_______, ________, _________are found in both DNA and RNA
__________ in DNA
__________ in RNA
Adenine, guanine, cytosine
Thymine (DNA)
Uracil (RNA)
two sugar phosphate backbones run in arrangement called ________
antiparallel
- a biologically functional molecule that consists of one
or more polypeptides (polymers of amino acids), each folded and coiled into a specific three-dimensional structure
proteins
roughly spherical proteins
shaped like long fibers
globular proteins
fibrous proteins
folding of proteins are done by
chaperonins
unravels and loses its native shape by a process called
denaturation
it is a linked series of amino acids with a unique sequence
Primary structure
This is collectively referred to as coils and folds, which are the result of hydrogen bonds between the repeating constituents of the polypeptide backbone
Secondary structure
a delicate coil held together by hydrogen bonding between every fourth amino
acid
a- helix
two or more strands of the polyopeptide chain lying side by side (called b strands) are connected by hydrogen bonds between parts of the two parallel polypeptide backbones
b pleated sheet
It is the overall shape of a polypeptide resulting from interactions between the side chains (R groups) of the various amino acids
Tertiary structure
caused by the exclusion of nonpolar substances by the
water molecules
Hydrophobic interaction
_____________ are between polar side chains and ____________ are between positively and negatively charged side chains
Hydrogen and ionic bonds
are formed when two cysteine monomers which have sulfhydryl groups (-SH) on their side chains are brought closer together by the folding of protein
Disulfide bridges
It is the overall protein structure that results from the
aggregation of these polypeptide subunits
Quaternary structure
Proteins function as
enzymes
storage of amino acids
coordinator of an organism’s activities
movement
protection against disease
transport of substances
response of cell to a chemical stimuli
support
- are the one class of biomolecules that does not include true polymers, and they
are generally not big enough to be considered as macromolecules - They are grouped together
because they mixed poorly with water
Lipids
These are not polymers but are large molecules assembled from smaller molecules by
dehydration reaction
Fats
A fat is constructed from two kinds of smaller molecules:
glycerol and
fatty acids
an alcohol; each of its three carbons bear a hydroxyl group
Glycerol
has a long carbon skeleton, having a carbon at one end which is a part of the carboxyl group
fatty acid
These are formed if there are no double bonds between
carbon atoms composing a chain, then as many hydrogen atoms as possible are
bonded to the carbon skeleton.
Saturated fatty acid
It has one or more double bonds , with one fewer
hydrogen atom on each double-bonded carbon. Its double bonds are cis which has
kinks to prevent the molecules from packing together closely enough to solidify at
room temperature
Unsaturated fatty acid
is similar to a fat molecule but has only two
fatty acids attached to glycerol rather than three. The two ends of phospholipids show
different behavior toward water.
Phospholipids
When phospholipids are added to water, they self-assemble
into double-layered structures called
bilayers
These are lipids characterized by a carbon skeleton consisting of four fused rings.
Different steroids are distinguished by the chemical groups attached to the rings
Steroids
a steroid, is a crucial molecule in animals since it is a component of animal cell membranes
and is also the precursor from which other steroids are synthesized, such as the sex
hormones
Cholesterol
include both sugars and polymers of sugars
Carbohydrates
the monomers from
which more complex carbohydrates are constructed
monosaccharides, or simple sugars
double sugars,
consisting of two monosaccharides joined by a covalent bond
Disaccharides
polymers composed of many sugar building blocks
polysaccharides
these are simple sugars which generally have formulas that are some
multiple of the unit CH2O
Monosaccharides
the most common monosaccharide, is of
central importance in the chemistry of life
Glucose (C6H12O6)
consists of two monosaccharides joined by a glycosidic linkage, a
covalent bond formed by a dehydration reaction
Disaccharides
are macromolecules, polymers with a few thousand monosaccharides
joined by linkages
Polysaccharides
