Core Concept: Chemical elements are joined together to form biological compounds Flashcards
What gives water its properties
its a polar molecule which allows hydrogen bonds between molecules
Properties of water and their function
five points
solvent - Can dissolve polar substances
is a metabolite - Water is a reactant in photosynthesis and hydrolysis, produced in aerobic respiration and condensation.
high specific heat capacity - means aquatic enviroments are stable and not susceptible to high temperature changes
high latent heat of vaporisation -allows evapoouration for cooling
high surface tention - support small light organisms on its surface
General formula of amino acids
NH2CH(R)COOH
How many amino acids are there and What makes each amino acid different
20 the varable group (R) is different
What is 2 amino acids linked together called
dipeptide
What bonds hold amino acids together
peptide bonds
What is a polypeptide
multiple amino acids joined together to form a long chain
Primary structure of proteins and bonds
polypeptide sequence
peptide bonds
Secondary structure of proteins and bonds
alpha helicas and beta pleated sheets
peptide and hydrogen bonds
Tertiary structure of proteins and bonds
the attraction of the R groups causes a tertiary structure which is either globular or fibrous
peptide, hydrogen, ionic, disulphide bonds and hydrophobic interactions
Quaternary structure of proteins
when more than one polypeptide chain in the protein eg Haemoglobin
Describe Fibrous proteins
provide an example
structural function and have long thin molecules and are insoluble they are parallel chains or sheets with many cross links making them strong, tough and stable
collegen
Describe globular proteins
provide an example
metabollic function compact and spherical shape they are soluble and function as enzymes and hormones
enzymes
Name the Test for proteins
buiret test
Describe the test for proteins and state any observations
buiret reagent is added
solution turns blue to purple if present
Define organic
containing a high Proportion of carbon atoms
Define monosaccharide
And its general formula
an individual sugar molecule they are the building block for comlex carbohydrates
(CH2O)n
Define triose, pentose and hexose
And an example of each
Triose has 3 carbons - triose phosphate
pentose has 5 carbons - ribose
hexose has 6 carbons - glucose
Functions of monosaccharides
four
source of energy
monomer in polypeptides
constituent in nucleic acids and ATP
Intermediate in respiration and photosynthesis
Define Disaccharides
two monosaccharides joined together in a condensation reaction to form a glycosidic bond
Name three disaccharides, their biological role and their monosaccharide constituents
maltose- glucose and glucose - in germinating seeds
sucrose - fructose and glucose - transport in the phloem of plants
lactose - galactose and glucose - in mammalian milk
Define Polysaccharides
multiple monosaccahride monomers joined by glycosidic bonds to form a long chain carbohydrate
Name four polysaccharides
starch
cellulose
glycogen
chitin
describe the function, structure and bonds of Starch
name its monomers
used in plants as energy storage as it is insoluble compact and stored in a small place and can be hydrolysed to release high ammounts of energy in its C-H and C-C bonds.
startch contains amylose and amylopectin
amylose is unbranched snd has a alpha helicas stucture with 1,4-glycosidic bonds
amylopectin which is a highly branched straight chain molecule
that has 1,4-glycosidic bonds and 1,6-glycosidic bonds causing the branching (means more quickly hydrolysed)
describe the function, structure and bonds of glycogen
name its monomers
used as energy storage in animals as its hydrolysed quickly and is able to be compact and have a high energy stored in the many C-C and C-H bonds
they have shorter 1,4-glycosidic bonds than amylopectin and so are more branched with and 1,6-glycosidc bonds
describe the function, structure and bonds of cellulose
name its monomers
monomers are b-glucose
used in cell walls of plants
each b gllucose is rotated 180 degrees to allow the formationof hydrogen bonds between layers (cross linked)1,4 glycosidic bonds only
describe the function, structure and bonds of chitin
name its monomers
b-glucose
in exoskeletons of insects and in fungal cell walls
some OH groups replaced with acetylamine glucose rotatated 180 degrees between bonds so H bonds enable cross linkage between chains chitin is strong, waterproof and lightweight
1,4-glycosidic bonds only
Describe the Test for starch
iodine is added
solution turns from brown/orange to it blue/black
Describe the Test for reducing sugar
heat with benedicts reagent
goes from blue to green to orange to brick red depending on concentration
Define inorganic
molecule or ion contining no more than one carbon atom
Function of Mg2+,Fe2+,PO(4)3- and Ca2+
Mg2+ - component in chlorophyll
Fe2+ - component in haemoglobin
PO(4)3- - component in phospholipids and nucleic acids
Ca2+ - component in bones and teeth
Describe the components bonds and formation of Triglycerides
glycerol and three fatty acid tail
condensation reaction forming ester bonds between each fatty acid tail and the glycerol
Describe the components, formation and properties of a phospholipid
glycerol, phospahte group and 2 fatty acid tails
hydrophillic phosphate head
hydrophobic fatty acid tails
Define saturated ( fat or oil)
containing no C=C bonds only C-C
fat (solid)
Define unsaturated ( fat or oil)
containing one (monounsaturated) or two or more (polyunsaturated) C=C bonds (Oil)
Roles of phospholipids
and Structure
2 points
component in cell membranes
electrical insulation in the myelin sheath
have a polar hydrophillic phosphate head and two non polar hydrophobic fatty acid tails
Roles of triglycerides
4 points
thermal insulation
protection
metabolic water
energy storage
Roles of waxes
waterproofing
Test for lipids (fats and oils)
Emulsion test
add ethanol and water
shake and emulsion appears (cloudy white)
Describe complications of a poor high density saturated fat diet
Atherosclerosis and heart failure
What are LDL
low density lipoproteins
cause build up of solid fats (Atheroma) in arteries
made after digestion
saturated lipid+proteins
What are HDL
high density lipoproteins
carry LDLs away to the liver for disposal
made after digestion
unsaturated lipid+proteins
