atoms to macromolecules Flashcards
1
Q
what is biological chemistry
A
- determines the structure of all components of life
- structure determines the function
2
Q
what is the structure of an atom
A
- composed of subatomic particles (protons, neutrons, electrons)
- protons and neutrons inhabit nucleus
- electrons surround nucleus in shells (2, 8, 8, 8)
3
Q
describe the distribution, chemical behaviour and electronegativity of electrons
A
- electron shells
- chemical behaviour: determined by distribution of electrons in electron shells
- electronegativity: value that denotes how tightly atoms hold onto their electrons, how easily electrons are given up / taken away
- increased value = increased electronegativity = stronger pull of shared electrons = valence shell
4
Q
why is water important
A
- biological unit of life
- absence of water = lack of activity, shape is important
5
Q
what are covalent bonds (types) and water as an example
A
- strong double bond formed by the SHARING of electrons between elements
- non polar covalent bond: even sharing of e-
- polar covalent bond: uneven sharing of e- (partial charges ẟ -ve and ẟ +ve)
- O is more electronegative than H, shared e- pulled more toward O
6
Q
what are ionic bonds
A
- weak bond formed by the transfer of electrons, loss / gain of electrons
- forms ions, cation and anion bonded by opposite charges
7
Q
what are hydrogen bonds
A
- attractive interaction between partial positive chart on the hydrogen atom and an electronegative atom (F, O, N)
8
Q
what are hydrophobic interactions of the cell membrane
A
- organised in a way that the molecules are orientated in a certain way (heads hydrophilic and tails hydrophobic)
- water is polar, no H bond it would be swapped around
9
Q
how does water dissociate
A
- 2H2O H3O+ + OH-
- reversible reaction
- form naturally, high H+ then = acidic solution, high OH- = basic
- determines chemical nature, pH scale
- water is in a state of equilibrium in which water molecules dissociate at the same rate at which they are being reformed
10
Q
what are acids, bases and pH
A
- pH: concentration of H ions in solution, logarithm scale (-log10)
- acid: increased H conc. (HCl)
- base: decreased H conc. / increased OH conc. (NaOH)
- concentrations of H and OH are equal in pure water
11
Q
what are macromolecules
A
- nucleic acid, lipids, carbohydrates, proteins
- monomer: repeated units, building blocks, chains of monomers make polymers
- C-H = core, functional groups attached
- dehydration reaction (create, produces water)
- hydrolysis reaction (break, reacts with water)
12
Q
what are carbohydrates
A
- components: C, H, O
- bond: glycosidic linkage
- monomers: monosaccharides (simple sugar, glucose), disaccharides, polysaccharides (microfibrils / membrane)
- characteristic feature: energy storage, structure, 1:2:1
13
Q
what are lipids
A
- components: C, H, O, P / N
- bond: ester linkage bond
- monomers: glycerol / fatty acid
- characteristic feature: simple (wax, triglyceride), membrane (phospholipids), complex (steroid / cholesterol, cell wall)
- saturated (no double bond, dense), unsaturated (double bonds, bending, loose)
14
Q
what are proteins
A
- components: C, H, O, N
- bond: peptide bond
- monomers: amino acids (NH2 and COOH bonded to C with H and R groups)
- characteristic feature: P (chain), S (H bond, alpha helices, beta pleated sheets), T (side chain interactions, 3D folding), Q (multiple polypeptides, interaction of S)
- enzymes (amylase), structural (keratin), contractile (myosin), hormones (insulin), transport (haemoglobin), defence (antibodies
15
Q
what are nucleic acids
A
- components: C, H, O, N, P
- bond: polynucleotide / phosphodiestar, H between N groups
- monomers: nucleotides (N base, pentose monosaccharide, P group)
- characteristic feature: store, transmit, express genetic info
- DNA (double helix, A,C,G,T)
- RNA (single strand, A,C,G,U)
