2.1.2 bio molecules + water Flashcards
define a monomer
a monomer is a single individual unit which can be linked together
define a polymer
long chain molecules of repeating units (monomers) in a repeating pattern
what is polymerisation?
the process of making a polymer
which elements are most living things made from?
Carbon, Hydrogen, Oxygen, Nitrogen, Sulphur, Phosphorus
what are the benefits of the important positive electrolytes?
Ca = nerve impulse transmission, muscle contraction
Na = nerve impulse transmission, kidney function
K = nerve impulse transmission, stomatal opening
H = catalysis of reactions, pH determination
NH4 = involved in production of nitrate ions by bacteria
what are the benefits of the important negative electrolytes?
NO3 = supply nitrogen to plans to make proteins + amino acids
HCO3 = maintain blood pH
Cl = balance positive charge of Na and K
HPO4 = cell membrane, bone, nucleic acid, and ATP formation
OH = catalysis of reactions, pH determination
explain the structure of water?
formed by covalent bonds between O and H
electron pulled slightly more to O2 and slightly away from H2
causes uneven distribution of e- = POLAR MOLECULE
why do water molecules form hydrogen bonds?
polar molecules interact w/ each other
δ+ H attracts δ- O
causes molecules to stick together
causes properties which make water essential for life
explain why water is a good solvent?
splits apart ionic compounds so they dissolve
δ- O attracts +ive ions
δ+ H attracts -ive ions
e.g glucose, amino acids
explain why water is a good temperature buffer?
high energy is needed to raise temp of 1g of water by 1 degree = high specific heat capacity
due to high no. of hydrogen bonds
reduces temp fluctuations + gives stable habitat
what are the benefits of water having high SHV
high boiling point
use evaporation to cool off
e.g sweating and panting
why is water a good habitat?
stable environment due to SHC
forms a low density solid at low temps
creates an insulating layer so life can continue below
ice also gives habitat e.g polar bears
why is water a good transport medium?
water molecules are highly cohesive and adhesive (cause high surface tension)
allows water to flow in columns and through tubes
e.g blood vessels and xylem
good solvent = transport dissolved substances
what does ‘water is a metabolite’ mean?
it is involved in many reactions in organisms
hydrolysis and condensation reactions = use water it build or break bonds
photosynthesis = raw material
