Week 2: Atomic Structure & Biomolecules Flashcards
atoms are made up of
protons, neutrons, and electrons
4 most important atoms for living things
hydrogen, carbon, nitrogen, and oxygen
atomic number
the number of protons in an atom’s nucleus
atomic mass
the sum of protons and neutrons in the nucleus
the closer an electron is to the nucleus
the more tightly it is held to the atom, making it more stable
the chemical reactivity of an atom depends on the state of
it;s outermost electron shell
electron affinities
how strongly an atom can attract an electron
ionic bonds
occurs when a positively and negatively charged ion attract one another
covalent bons
occur when two atoms share an electron to complete their shells
non-polar covalent bonds
share electrons equally between the atoms that make up the bond bc of identical electron affinities
polar covalent bonds
share electrons unequally bw the atoms that make up the bond bc of different electron affinities
the unequal sharing of electrons in polar covalent bonds results in
molecule that has a slight charge difference across the individual molecule (hydrogen bonding)
the polarity of a molecule will define its ability to
interact with water
hydrophilic
polar and ionic compounds
hydrophobic
non polar compounds
four main classes of biomolecules important for all living things
carbohydrates, lipids, proteins, nucleic acids
carbs are responsible for
energy storage and structural molecules
lipids are responsible for
energy storage
proteins are responsible for
numerous biological processes
nucleic acids are responsible for
directing the synthesis and assembly of proteins
what are the subunits that make up larger carbohydrates
monosaccharides
lipids are used by cells for two main purposes
cell membrane structure, energy storage
main structure of a lipid molecule consists of
glycerol & 3 fatty acid chains
what defines the lipid molecule
variability in the fatty acid chain
saturated fatty acid
all carbons have single bonds bw them allowing them to bond with the maximum potential of H atoms
unsaturated fatty acids
have one or more locations where a double bond exists between carbon molecules
amino acids are
the individual subunits that make up protein molecules
amino acids are made up of
amino group, carboxyl group, and R group
the _________ gives amino acid molecules its unique properties
R group
bond that forms between two amino acids is called
peptide bond
what can make a protein denatured
pH level & high temps
what are enzymes
protein molecuels that reduce the activation energy of a chemical rxn
nucleotides are
the individual monomers that make up nucleic acid molecules (DNA & RNA)
3 main components of nucleotides
5 carbon sugar, phosphate group, nitrogenous base
pyrimidines
cytosine, thymine, and uracil
single ring structure
purines
adenine, guanine
double ring structure
DNA structure
double stranded molecule, arranged in helical shape
RNA structure
single stranded
