M2, C3 Biological Molecules Flashcards
what are all living things primarily made of
carbon
hydrogen
oxygen
nitrogen
phosphorus and sulphur are also important
whats a covalent bond
when two atoms share a pair of electrons. present in the outer orbitals of the atoms
what are the bonding rules for carbon, nitrogen, oxygen and hydrogen?
carbon - 4 bonds
nitrogen - 3 bonds
oxygen - 2 bonds
hydrogen - 1 bond
whats the displayed formula for:
a) carbon dioxide
b) hydrogen
c) water
a) O=C=O
b) H-H
c) H-O-H
what’s a cation
when an atom or molecule loses one or more electrons and it gets a net positive charge
what’s an anion
when an atom or molecule gains electrons and it gets a net negative charge
what are ions in solutions called
electrolytes
what is an ionic bond
when an atom loses or gains electrons
forms positive or negative ions
held together because of the attraction of opposite charges
what are the uses of calcium ions?
nerve impulse transmission
muscle contraction
what are the uses of sodium ions?
nerve impulse transmission
kidney function
what are the uses of potassium ions?
nerve impulse transmission
stomatal opening
what are the uses of hydrogen ions?
catalysis of reactions
pH determination
what are the uses of ammonium ions?
production of nitrate ions by bacteria
what are the uses of nitrate ions?
nitrogen supply to plants for amino acid and protein formation
what are the uses of hydrogen carbonate ions?
maintenance of blood pH
what are the uses of chloride ions?
balance positive charge of sodium and potassium ions in cells
what are the uses of phosphate ions?
cell membrane formation
nucleic acid and ATP formation
bone formation
what are the uses of hydroxide ions?
catalysis of reactions
pH determination
define polymer
long chain molecules made by linking monomers.
give examples of monomers
glucose, amino acid, nucleotide
give examples of polymers
glycogen, protein, DNA, starch
what does it mean saying a water molecule is polar
the oxygen atom is slightly more negative and the hydrogen atoms are slightly more positive
this means it forms hydrogen bonds
what are the 9 properties of water
universal solvent liquid at room temp specific capacity latent heat of vaporisation latent heat of fusion density capillarity surface tension wetness
what does the universal solvent property in water mean
water can dissolve many substances
enables many chemical reactions to occur in the cell cytoplasm. And enables substances to be transported eg. xylem