Biological Molecules

Flashcard maker : Lily Taylor
Polymers
A large molecule consisting of many identical or similar molecular units, called monomers, covalently joined together in a chain
monomer
A chemical sub-unite that serves as a building block of a polymer
Dehydration reaction
A chemical process in which two molecules become covalently bonded to each other with the removal of a water molecule
Hydrolysis
A chemical process in which polymers are broken down by the chemical addition of water molecules to the bonds linking their monomers; and essential part of digestion
enzyme
a protein that serves as a biological catalyst, changing the rate of a chemical reaction without itself being changed into a different molecule in the process
Carbohydrates
Member of the class of biological molecules consisting of simple single- monomer sugars (monosaccharides), two monomer sugars (disaccharides) and other multiunit sugars (polysaccharides)
monosaccharide
The simplest carbohydrate, a simple sugar with a molecular formula that is generally some multiple of ch6o. the building blocks for disaccharides and polysaccharides
Disaccharides
A sugar molecule consisting of two monosaccharides, linked together by a dehydration reaction
Polysaccharide
A carbohydrate polymer consisting of hundereds to thousands of monosaccharides linked by dehydration synthesis
Starch
a storage polysaccharide found in the roots of plants and certain cells; polymer of glucose
Glycogen
an extensively branched polysaccharide of many glucose monomers; serves as an energy-storage molecule in liver and muscle cells; the animal equivalent of starch
cellulose
A large polysaccharide composed of many glucose monomers linked into cable-like fibers that provide structural support in plant cells
lipid
An organic compound consisting mainly of carbon and hydrogen atoms linked by non polar covalent bonds making the compound mostly hydrophobic. Include fats, phospholipids, and steroids and are insoluble in water
hydrophobic
“water- fearing” non polar molecules that do not dissolve in water
fat
A large lipid molecule made from an alcohol called glycerol and three fatty acids; most function as energy storage molecules
unsaturated
Pertaining to fats and fatty acids whose hydrocarbon chains lack the maximum number of hydrogen atoms and therefore have one or more double covalent bonds. do not solidify at room temperature
Saturated
Pertaining to fats and fatty acid whose hydrocarbon chains contain the maximum number of hydrogens and therefore have no double covalent bonds. solidify at room temperature
phospholipids
A lipid made up of glycerol joined to two fatty acids and phosphate group, giving the molecule a non polar hydrophobic tail and a hydrophilic head- bilayers that function as biological membranes
steroid
A type of lipid whose carbon skeleton is in the form of four fused rings with various chemical groups attached examples are cholesterol, testosterone, and estrogen
cholesterol
A steroid is an important component of animal cell membranes and that acts as a precursor molecule for the synthesis of other steroids and molecules
Proteins
A functional biological molecule consisting of one or more polypeptides folded into a specific three-dimensional structure
amino-acids
An organic molecule containing a carboxyl group and an amino group; serves as the monomer of proteins
peptide bonds
The covalent linkage between two amino acid units in a poly-peptide; formed by a dehydration reaction
Poly-peptide
A polymer (chain) of amino acid linked by peptide bonds
Denaturation
A process in which a protein unravels, losing its specific structure and hence function; can be caused by changes in pH or salt concentration or by high temperature. Also refers to the separation of the two strands of the DNA double helix, caused by similar factors.
Primary Structure
The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain.
Secondary structure
The second level of protein structure; the regular local patterns of coils or folds of a polypeptide chain.
Alpha Helix
The spiral shape resulting from the coiling of a polypeptide in a protein’s secondary structure.
pleated sheet
the folded arrangement of a polypeptide in a protein’s secondary structure
Tertiary structure
The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain.
quaternary structure
The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits.
nucleic acids
A polymer consisting of many nucleotide monomers; serves as blueprint for proteins and, through the actions of proteins, for all cellular structures and activities. DNA, RNA
Gene
a discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses)
DNA
A double stranded helical nucleic acid molecule consisting of nucleotide monomers with deoxyribose sugar and nitrogenous base adenine (A), Cytosine (C), Guanine (G), and Thymine (T)- capable of replicating, it is an organism’s genetic material
RNA
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
Nucleotides
A dense region of DNA in a prokaryotic cell
Double helix
The native form of DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape

Get instant access to
all materials

Become a Member