BIOL 1951: Biomolecules

Covalent bond

A chemical bond in which two atoms share a pair of electrons

Polar covalent bond/polar bond

A covalent bond between two atoms that have different electronegativities

hydrogen bond

A weak chemical attraction between a partially positive hydrogen atom of a polar molecular and a partially negative atom of another polar molecule

Organic molecule

A carbon-containing molecule found in living organisms

isomer

Two structures with an identical molecular formula but different structures and characteristics

functional group

A group of atoms with chemical features that are functionally important

monomer

An organic molecule that can be used to form larger molecules consisting of many repeating units of the monomer

polymer

A large molecule formed by linking many smaller molecules called monomers

monosaccharide

A single sugar molecule

polysaccharide

many monosaccharides linked to form long polymers

amino acid

The building blocks of proteins

peptide bond

The covalent bond formed between amino acids in a polypeptide

polypeptide

A linear sequence of amino acids

triglyceride

A molecule composed of three fatty acids linked by ester bonds to a molecule of glycerol

phospholipid

A class of lipids that are similar in structure to triglycerides, but the third hydroxyl group of glycerol is linked to a phosphate group instead of a fatty acid

amphipathic

Molecules containing a hydrophobic region and a hydrophilic region

lipid

A molecule composed predominantly of hydrogen and carbon atoms

carbohydrate

An organic molecule containing carbon including starches, sugars and cellulose

protein

A functional unit composed of one or more polypeptides

nucleic acid

An organic molecule composed of nucleotides

nucleotide

An organic molecule with one or more phosphate groups, a five-carbon sugar, and a single or double ring of carbon and nitrogen atoms known as a base

ribose

A five-carbon sugar found in RNA

sugar-phosphate

Make up the backbone of DNA or RNA

base

A component of nucleotides that is a single or double ring of carbon and nitrogen atoms

antiparallel

the arrangement in DNA where one strand runs in the 5' to 3' direction while the other strand is oriented in the 3' to 5' direction

DNA

The genetic material that provides a blueprint for the organization, development, and function of living things

RNA

One of two classes of nucleic acids that consists of a single strand of nucleotides

Lipids

Nonpolar molecules that are primarily composed of carbon and hydrogen, with some oxygen

glycosidic linkage

A covalent bond formed between two monosaccharides by a dehydration reaction

structural isomers

same atoms but different bonding relationships

stereoisomers

identical bonding relationships but different spatial relationships

enantiomers

Pair of molecules that are mirror images

Enzymes

Molecules that catalyze rates of chemical reactions

Condensation reaction

Two smaller molecules combine to form a polymer through this process, which produces a polymer and loses a water molecule

Hydrolysis reaction

Polymer broken down into monomers and a molecule of water is added back in

Monosaccharides

These can be broken down to ATP for energy

starch, glycogen, cellulose

examples of polysaccharides

Triglycerides

a lipid formed by bonding glycerol to three fatty acids

saturated fatty acid

All carbons in fatty acid are linked by single covalent bonds

Unsaturated fatty acid

Fatty acid with one or more double carbon bonds

Phospholipids

Third hydroxyl group of glycerol is linked to phosphate group instead of a fatty acid

Steroids

Formed by four fused rings of carbon atoms

Waxes

Contain one or more hydrocarbons, provide barrier to water loss

N-terminus

end of an amino acid

C-terminus

the carboxyl end of an amino acid

Primary structure

the amino acid sequence for a protein

secondary structure

certain sequences of amino acids form hydrogen bonds causing it to fold

Tertiary structure

Secondary structure and coiled regions fold into 3D shape

Quaternary structure

2 or more polypeptides bind to form a functional protein

protein subunits

individual polypeptides

cellulose

... is a polymer of glucose

polysaccharide

The largest molecule of the following (monosaccharide, disaccharide, glucose, polysaccharide)

a backbone of alternating phosphate and sugar groups, with nitrogenous bases protruding from the sugars

A single strand of DNA consists of

Sulfhydral:DNA

Which of the following functional groups is not paired with a molecule that can possess it?

-SH

The functional group that forms covalent bonds between R groups within a polypeptide and that stabilizes tertiary strcture is

Starch

Glycogen is to animal cells as ... is to plant cells

steroids

Subunits sometimes build up to form a macromolecule. Which molecule is least likely to be a subunit of a macromolecule?

2; 3

A phospholipid has ... fatty acids attached to glycerol, wheras a fat has ...

20%

If a specimen contains 30% adenine in its DNA, how much cytosine will it contain?

True

True or False: While nucleic acids have monomers that share a similar structure, lipids lack monomers and are in fact a diverse class of biological macromolecules