Definitions Flashcards
Covalent Bonds
Electrostatic attraction between the nucleus and shared pair of electrons
Ionic Bonds
When atoms donate or receive electrons from another atom
Cation
Positive ion that has more protons than electrons and has lost electrons
Anion
Negative ion that has more electrons than protons and has gained electrons
Polar
Has regions of negativity and positivity
Hydroxyl Group
A bond between an oxygen and hydrogen atom, is covalent (O-H)
Hydrogen Bond
The relatively weak attractions between molecules with a partially positive region and partially negative region.
Carbohydrates
Contain carbon, hydrogen and oxygen. Are hydrated carbons
Monosaccharide
One sugar unit e.g. glucose, fructose, ribose
Disaccharide
Two monosaccharides linked together e.g. sucrose, maltose, lactose
Polysaccharide
When multiple monosaccharides link together e.g. glycogen, cellulose and starch
Glycosidic Bond
The covalent bond between two glucose molecules
Condensation Reaction
When two hyroxyls in alpha glucose molecules join together
Isomers
Have the same molecular formula but a different structure
Ester Bonds
When hydroxyl groups between glycerol and fatty acids bond
Esterificiation
When ester bonds are made from glycerol and fatty acids to make triglycerides and water
Hydrophilic
Attracted to water
Hydrophobic
Repelled by water
Peptides
Polymers made up of amino acids which are the monomers
R-groups
The variable groups that are in the centre of amino acids and can make different amino acids
Peptide Bonds
The bonds between the hydroxyl group in the carboxyl group of one amino acid and the hydrogen in the amine group of the other amino acid
Alpha Helix
Shape of secondary structure of proteins when hydrogen bonds bend the amino acid chains
Beta Pleated Sheets
Other shape of secondary structure of proteins when there are hydrogen bonds between parallel amino acid chains
Disulfide bonds / Disulfide Bridges
Covalent bonds between two R-groups that have sulfur atoms in them
Nucleotide
Monomers of nucleic acids, have a base,phosphate group and pentose sugar
Phosphodiester Bond
The covalent bond between the phosphate group of the 5th carbon of one pentose sugar in one nucleotide and the hydroxyl group of the 3rd carbon of another pentose sugar in an adjacent nucleotide
Pyrimidine
Smaller bases which contain a single carbon ring structure e.g thymine,cytosine
Purine
Larger bases which contain a double carbon ring structure e.g adenine, guanine
RNA
Ribonucleic acid, it’s relatively short section of the large DNA molecule that can leave the nucleus to partake in protein synthesis
DNA
Deoxyribose nucleic acid it’s a large molecule that is in a double helix strand and contains all the genetic information.
Semi-conservative replication
When DNA is replicated there will always be one old strand from the parental DNA and one newly synthesised strand
Genetic code
A sequence of DNA bases that code for amino acids which in turn code for proteins
Codon
Three bases are called a codon and each codon can code for a specific amino acid
Gene
A section of DNA that contains the complete sequence of bases to code for an entire protein
Degenerate code
Many codons will code for one specific amino acids as there are 64 codons and 22 amino acids
mRNA
Messenger RNA which is a short section of DNA that has been transcripted so that it can leave the nucleus and travel to the ribosome for protein synthesis.
tRNA
Transfer RNA is the RNA which is needed for the translation to make proteins. It has 3 bases called an anticodon which binds to the codon of mRNA and it also carries an amino acid
Anticodon
Three bases that form complementary pairs with the codons of mRNA
ATP
Adenosine Triphosphate which is the universal energy currency as it transfers energy very easily and efficiently
