Bio Molecules Flashcards
What does tertiary structure determine
Function
Polypeptide chain will fold up differently due to interactions between r groups
What does temp and ph change affect
Temp-ionic + hydrogen bonds + h and h interactions
Ph - ionic bonds and hydrogen bond
=change in 3d shape
Why is starch + glucose good as storage molecules
INSOLUBLE - don’t affect WP
COMPACT - coiled shape (amylose) less space needed to fit m glycogen more coiled can fit more into less space , highly branched , more free ends where glucose can be added/ removed (released quickly)
BRANCHED - free ends where glucose can be added/ removed , amylopectin - 1,4+1,6 g bonds
Why is cellulose suitable to be plant wall
Forms HB w neighbouring chains , microfibrils
Flexible
Insoluble
Cholesterol
Insoluble
CHO
Lipid
Between phospholipid membranes, regulates fluidity
Makes steroids
Structure of collagen
Peptide bonds between wmino acids
Every 3rd amino acids is GLYCINE, small amino acid, allows 3 chains to be arranged close together in TRIPLE HELIX
few hydrophilic R groups (insoluble)
Adjacent molecules joined by CROSSLINKS ( cross links between chains),- strong fibres
Haemoglobin
Globular , hydrophilic R groups on outside
4 subunits , 2 alpha 2 beta
Haem- iron , as each oxygen binds alters quanterysnry structure to make binding of 02 molecules easier
Subunits joined by disulphide bonds
Tertiary structure - ionic , hydrogen , H+H interactions / bonds , secondary structure undergoes further coiling
Primary - chain of amino acids joined by peptide bonds
Secondary -alpha helix, small regions of beta pleated sheet , H bonds
How water properties help orgsjniks
High specific heat capacity - thermally stable environment , enzymes function correctly
Ice is less dense than water - water beneath ice is insulated
Solvent - medium for reactions , transport medium
Cohesion/adhesion - transpiration, surface tension - pondskaters
Uses of lipids
Thermal + electrical insulation (myelin sheath), makes up adipose tissue , protection around organs
Low density -buoyancy
Energy store/ source - insoluble can be stored no WP change , has a lot of C-H bonds when oxidised release lot of energy , release twice as much energy per gram as carbohydrate
Formation of bilayer
Metabolic water
Peptide bond formation
Bwteen amine group + carboxyl group
Condensation reaction ,water produced
Protein contains
C H O N
Primary structure
Sequence of amino acids in polypeptide chain , specific for each protein
Change in amino acid , change structure of whole protein
Test for lipids
Add ethanol + shake then add to water
Turn milky - present
Test for sugars
Reducing - copper sulfate gets oxidised to brick red copper oxide
Add Benedict’s solution , blue - yellow - green - orange-brick red , red = highest conc
Non -reducing - add HCL , break glycosidic bonds back to monosaccharide then add Benedict’s solution
For unknown conc- serial dilution and then use colorimeter get an absorbsnce value for each solution , calibration curve
Or jus compare colour or diff solutions to unknown to estimate conc
Test for protein
Biurets reagent
Blue-purple
Secondary structure
How to calibrate colorimeter
Set to zero absovrwnce using blank b distilled water
So all values are measured tk same standard , valid
