chemical and cellular basis of life - definitions Flashcards
Polarity
polarity is an uneven charge distribution within a molecule.
Hydrogen Bonds
Weak attractions between the slightly polar hydrogen atom of one water molecule and the slightly polar oxygen atom of the adjacent water molecule are known as hydrogen bonds.
Cohesion
Attraction between water molecules due to hydrogen bonding is known as cohesion
Adhesion
Attraction between water molecules and other substances
Carbohydrates
Carbohydrates are the most abundant group of organic compounds on earth with a major elemental composition of C, H, and O.
Hydrates of carbon contain the same proportion of H:O which equals to 2:1 as in water.
The general formula of carbohydrates is Cx(H20)y
Monosaccharides
The simplest form of carbohydrates having the general molecular formula of (CH2O)n are monosaccharides.
Disaccharides
They are the sugars formed by joining two monosaccharides by a glycosidic bond
Glycosidic Bond
A glycosidic bond is formed by the removal of a water molecule from two adjacent monosaccharides by a condensation reaction.
Polysaccharides
They are macromolecules and biopolymers made up of a few hundred to a few thousand monosaccharide subunits.
Lipids
Lipids are a diverse group of large hydrophobic molecules which are biological molecules but not considered as polymers or macromolecules.
They consist of C,H,O and H:O ratio is not 2:1. Comparatively more H is present.
Saturated Fats
Fats are made up of saturated fatty acids (fatty acids with hydrocarbons having no double bonds)
Unsaturated Fats
Fats are made up of unsaturated fatty acids (fatty acids with hydrocarbons having one more more double bonds)
Phospholipids
Phospholipids are major components of cells membranes composed of two fatty acids and one phosphate group attached to one glycerol molecule.
Proteins
Proteins are made up of amino acids and has an elemental composition of C, H, O, N and S
Primary Structure of Proteins
The unique sequence of linearly arranged amino acids linked by peptide bonds is the primary structure of proteins.
Secondary Structure of Proteins
When the primary structure of a single polypeptide chain coils and folds, as a result of intra molecular hydrogen bonds between the oxygen atoms and hydrogen atoms attached to the nitrogen atoms of the same poly peptide chain backbone to form the secondary structure.
Tertiary Structure of Proteins
Usually the secondary polypeptide chain bends and golds extensively forming a precise compact unique, functional and three-dimensional shape resulting from the interactions between the side chain/R-group of amino acids.
Quaternary Structure of Proteins
The aggregation of two or more polypeptide chains involve in the formation of one functional protein. Separate chains are called sub units which were held together by inter and intra-molecular bonds.
Denaturation of Proteins
Denaturation of proteins is the loss of its specific chemical three dimensional shape due to the alteration of weak chemical bonds and interactions.
Nucleic Acids
Nucleic acids are polymers that exist as polynucleotides made up of monomers called nucleotides containing C,H,O,N and P
Base Pair Rule
Always a purine base, pairs with a specific pyrimidine base
