module 2- biological molecules Flashcards
which 4 elements are the most important in living organisms ?
- hydrogen
- oxygen
- carbon
- nitrogen
which 2 elements are also really important for living organisms ?
- phosphorous
- sulfur
what is bonding determined by ?
- the number of unpaired electrons present in the outer orbitals of different elements
how many bonds to carbon atoms from with other atoms ?
4
how many bonds can nitrogen atoms form with other atoms ?
3
how many bonds can oxygen atoms form with other atoms ?
2
how many bonds can hydrogen atoms form with other atoms ?
1
what is a covalent bond ?
a strong bond where 2 atoms share a pair of electrons
what is an ionic bond ?
1 atom in a pair donates an electron and the other receives it forming 1 positive ion and 1 negative ion, held together by opposite charges
what is an ion ?
an atom/molecule where the total number of electrons isn’t equal to the total number of protons
what type of ion is positively charged and what type of atom is negatively charged ?
cation - positive
anion - negative
what are hydrogen bonds ?
a slightly negatively charged atom binds to a slightly positively charged hydrogen atom
what are molecules contained carbon described as ?
organic
which elements are in water ?
hydrogen
oxygen
what elements are in a carbohydrate ?
carbon
hydrogen
oxygen
what elements are in a lipid ?
carbon
hydrogen
oxygen
what elements are in a protein ?
carbon
nitrogen
hydrogen
sulfur
oxygen
what elements are in nucleic acid ?
- carbon
- nitrogen
- oxygen
- hydrogen
- phosphorus
what happens when mineral ions are dissolved in solution ?
they are electrolytes
what are calcium ions used for ?
nerve impulse transmission
muscle contraction
what are sodium ions used for ?
nerve impulse transmission
kidney function
what are potassium ions used for ?
nerve impulse transmission
stomatal opening in leaves
what are hydrogen ions used for ?
catalyzing many reactions
ph regulation
what are ammonium ions used for ?
used by bacteria to make nitrate ions
used by plants to make up proteins
what are nitrate ions used for ?
the form plants take up nitrogen
used by plants to make proteins
what are hydrogen carbonate ions used for ?
to maintain blood plasma pH
what are chloride ions used for ?
to balance positive charges of sodium and potassium ions in cells
what are phosphate ions used for ?
cell membrane and formation
formation of nucleic acids
bone formation
what are hydroxide ions used for
- catalyzing reactions
- pH regulation
what is an anabolic reaction ?
where smaller molecules join to form larger ones
what is a catabolic reaction ?
where larger molecules are broken down into smaller ones
what is a monomer ?
a small single molecule which joins together to make a polymer
what is a polymer (macromolecule )
a large molecule made up of monomers
what is a condensation reaction ?
when 2 molecules join together involving the removal of water
what is a hydrolysis reaction ?
when a molecule is split apart involving the addition of water
what is a hydrolysis reaction ?
when a molecule is split apart involving the addition of water
what is starch used for ?
an energy store for plants
how is starch formed ?
alpha glucose molecules joined by glycosidic bonds to form 2 different polysaccharides
what are the 2 types of starch ?
amylopectin
amylose
what substance in plants is stored by starch
glucose
how is amylose formed ?
by alpha glucose molecules joined together by 1-4 glycosidic bonds
give properties of amylose
- helix shape ( formed by long chains of glucose which twist ) - these are stabalised by hydrogen bonds
how does the helix shape of amylose help with its function ?
it makes the polysaccharide more compact and less soluble than the glucose molecules used to make it
how is amylopectin formed ?
by 1-4 glycosidic bonds between alpha glucose molecules and glycosidic bonds between carbon 1-6 via condensation reaction
what type of shape / structure does amylopectin form ?
a branched structure
what is glycogen used for ?
in animals and fungi it is used as an energy storage molecule
glycogen forms more branches than amylopectin, how is this useful ?
it makes it more compact, needs less space to be stored
animals are more mobile so use more energy so need more energy storage space
how does branching help with glycogen ?
there are lots of free ends where glucose can be added or removed which speeds up the process
of storing or releasing glucose
what similar properties do amylopectin and glycogen have which makes them good for storage ?
insoluble branches and compact
why is starch a good energy store ?
it isn’t soluble so doesn’t affect the water potential of a cell
it is unreactive
it is compact and doesn’t take up much space to store
it releases energy quickly as there are lots of end points to release glucose from via hydrolysis using enzymes
why is glycogen a good energy store ?
-it is insoluble
-it has a branched structure = quick energy release
- doesn’t effect water potential of cell
- 1-4 glycosidic bonds = easy to make and break
- coiled up shape, easy to store
-
glucose is stored as starch or glycogen until it is needed for what process ?
respiration
to release glucose molecules from starch/glycogen, what reaction needs to occur ?
a hydrolysis reaction
what does a hydrolysis reaction do ?
addition of water molecules
this reverse the condensation reaction which forms the glycosidic bond
how is the hydrolysis reaction catalyzed ?
by enzymes
how is the hydrolysis reaction catalyzed ?
by enzymes
what is cellulose used for ?
in plant cell walls for structure and support
how is cellulose formed ?
by beta glucose which are joined together by every other molecule being flipped 180 degrees
in between each molecule a hydrogen bond links them
what type of chain molecule is formed in cellulose
a straight chain molecule
cellulose molecules are linked together by hydrogen bonds forming strong fibres
called what ?
microfibrils
microfibrils join to form what in cellulose ?
macrofibrils
what do macrofibrils join together to form what ?
fibres
how are macrofibrils strong ?
- they combine to produce forbes which are interwoven
- they are embedded in a gel like structure called pectin
why is cellulose ideal for the structure of cell walls ?
- microfibrils have high tensile strength due to glycosidic bonds betweeen individual glucose molecules and hydrogen bonds holding cellulose chains together
- macrofibrils are criss crossed ( in different directions )
- cellulose is embedded in pectin
why is cellulose hard to digest ?
most animals don’t contain enzyme cellulose
cellulose usually passes through digestive system and is used as a source of fibre
what are polysaccharides
large polymers made by joining lots of monosaccharides together by condensation reactions making long chains
how are monosaccharides joined (bonds)
glycosidic bonds
how do you test for simple sugars (all monosaccharides and most disaccharides )
benedict’s test
how do you test for non reducing sugars (sucrose)
modified benedict’s test
how do you test for starch ?
iodine test
what are lipids ?
molecules containing hydrogen carbon and oxygen
generally fats/oils
what state are fats at room temperature ?
solid
what state are oils at room temperature ?
liquid
what are the properties of lipids ?
- they are soluble in organic solvents
- they are NOT soluble in water
- they are non polar molecules
- hydrophobic
what does non polar mean ?
the electrons of the molecule in outer orbitals are evenly distributed so there are no positive or negative areas so don’t form hydrogen bonds
what does hydrophobic mean ?
repels water
what are simple lipids known as ?
triglycerides
how many glycerol molecules to fatty acids are there in a triglyceride ?
1 glycerol molecule : 3
fatty acids
what chemical group is glycerol in ?
alcohols
what chemical group are fatty acids in ?
carboxylic acids (-COOH)
what type of bonds form between glycerol and fatty acids ?
ester bonds
known as esterification
forming a triglyceride is a condensation reaction, how are 3
water molecules formed ?
both glycerol and fatty acids have hydroxyl groups forming 3
water molecules and bonds between glycerol and fatty acids
what is needed for a triglyceride to break down ?
3 water molecules
then hydrolysis can take place
what does a saturated lipid mean ?
there are no double bonds between carbon atoms in fatty acid chains
what does an unsaturated lipid mean ?
there is 1 double bond between carbon atoms in a fatty acid
what does a polyunsaturated lipid mean ?
there is more than 1 double bond between carbon atoms
how are double bonds less compact ? if
double bonds cause the molecule to kink
why are unsaturated fats often liquid at room temp ?
there is a kink at double bonds which makes them less compact in arrangement
what can lead to obesity ?
excess fat
what are phospholipids ?
modified triglycerides which contain phosphorus carbon oxygen and hydrogen
where are phosphate ions (PO43-) found ?
cytoplasm of cells
how are phosphate ions soluble in water ?
they have extra electrons which caused them to be negatively charged
what is replaced with a phosphate group to form a phospholipid ?
1 fatty acid
the phosphate end of the phospholipid is charged and can therefore dissolve in water, how could we describe this as ?
it is hydrophilic
the fatty acid end of a phospholipid is non polar and a long chain of hydrocarbons, what could we call this ?
the hydrophobic end
the phospholipid had two ends, what are these 2 ends ?
the tail which is non polar, repelling water and called hydrophobic
the head which is charged, attracting water, and called hydrophilic
what does hydrophobic mean ?
repels water
what does hydrophilic mean ?
attracts water
how to phospholipids work with water ?
they form a layer on the surface of water
phosphate heads are in the water with the fatty acid tails sticking out
what are surface active agents/surfactants ?
phospholipids in water
describe how phospholipids form a bilayer in water
phospholipids form a 2 layered sheet arrangement with the hydrophobic tails pointing inwards with the hydrophilic heads protecting them from water ?
how does the bilayer phospholipids form help with cells ?
- they help to form cell membranes
- they are able to separate the aqueous environment in which cells usually exist from the aqueous cystol within cells
how does the bilayer phospholipids form help with cells ?
- they help to form cell membranes
- they are able to separate the aqueous environment in which cells usually exist from the aqueous cystol within cells
what are sterols ?
a type of lipid known as steroid alcohols
found in cells
how are sterols structured ?
- complex alcohol molecules based on a 4 ring carbon structure with a hydroxyl group at one end
- have hydrophilic and hydrophobic characteristics
how are sterols structured ?
- complex alcohol molecules based on a 4 ring carbon structure with a hydroxyl group at one end
- have hydrophilic and hydrophobic characteristics
what part of sterols is hydrophobic and what part is hydrophilic ?
hydroxyl group = hydrophilic
rest of molecule = hydrophobic
give an example of a sterol ?
cholesterol
where is cholesterol made ?
liver
intestines
what does cholesterol do ?
plays a role in the formation of cell membranes
what does cholesterol do ?
plays a role in the formation of cell membranes
adds stability and regulates fluidity of cell membranes
where is cholesterol positioned ?
between phospholipids with a hydroxyl group at the periphery of the cell membrane
how does cholesterol regulate the fluidity of cell membranes !
it keeps them at low temperatures and stops them being too fluid at high temperatures
give examples of what cholesterol manufactures
vitamin d
steroid hormones
bile
give the roles of lipids ?
- membrane formation and creation of hydrophobic barriers
- hormone production
- electrical insulation needed for impulse transmission
- waterproofing
- long term energy storage
how are lipids used as a long term energy storage ?
- for thermal insulation to reduce heat loss
- cushioning to protect
vital organs - adds buyancy for aquatic animals e.g whales
how do you test for lipids ?
emulsion test
describe how to carry out the emulsion test
- mix sample with ethanol
- mix solution with water
- shake
- if white emulsion forms at the top a lipid is present
what is food synergy ?
where nutrients don’t work in isolation, they work as part of the combined effect of a whole range of nutrients
which type of fat is healthier and why ?
unsaturated
which type of fats do plants generally contain ?
- unsaturated triglycerides, normally as oils
what type of fats do animals generally contain ?
saturated triglycerides normally as solids
why would people want to find a substitute for butter ?
it his high in saturation as it is made from cows milk
how have scientists tried to make butte healthier in the past ?
using vegetable oils and using hydrogen to remove double bonds to make it a solid = MARGARINE
why did the initial method of making margarine / healthier butter not work ?
when breaking the double bonds a by product called trans fat was produced
what is an advantage of trans fat ?
it increases shelf life
what is a disadvantage of trans fat ?
it is linked to corornary heart disease
what do scientists now use when making a substitute for butter ?
they use mono/poly saturated plant oils
what is an advantage of using mono/polysaturated plant oils in butter substitutes ?
it reduces high cholesterol levels which reduce the development of coronary heart disease
what are carbohydrates ?
molecules which contain hydrogen carbon and oxygen
what is the formula for carbohydrates ?
(CH2O)n
what are carbohydrates also known as ?
saccharides/sugars
what are carbohydrates also known as ?
saccharides/sugars
what are monosaccharides ?
single, simple sugars
give an example of monosaccharides ?
glucose
i
what are disaccharides ?
complex sugars, 2 monosaccharides joined together
give an example of a disaccharide ?
maltose
what is a polysaccharide ?
NOT a sugar
2+ monosaccharides joined together
give an example of a polysaccharide
glycogen
what is the formula of glucose ?
C6H12O6
describe the structure of glucose ?
- it is a monosaccharide composed of 6 carbons
- contains 5 OH groups
- has a C:O ratio of 1:1
what is a hexose monosaccharide ?
a monosaccharide composed of 6 carbons
what are the 2 variations of glucose ?
alpha
beta
what are the 2 variations of glucose ?
alpha
beta
what is the difference between alpha and beta glucose ?
the OH groups are switched
what is the difference between alpha and beta glucose ?
the OH groups are switched
glucose molecules are polar, what does this mean ?
they are soluble in water and have hydrogen bonds which from between the hydroxyl groups and water molecules
how does glucose being polar a good thing ?
it allows glucose to be dissolved in the cytosal of a cell
describe a condensation reaction between 2 glucose molecules ?
2 alpha molecules are side by side and the 2 hydroxyl groups react so the bonds are broken and new bonds are reformed in different places forming new molecules
what type of bond is formed between the 2 OH molecules when glucose reacts in a condensation reaction ?
glycosidic bond
why is the glycosidic bond in aloha glucose molecules known as a 1,4 glycosidic bond ?
the bond happens between carbon 1 and 4
describe the formation of maltose ?
2 hydrogen and 1
oxygen atom are removed form the glucose monomers and join to form water
a bond forms between C1 & C4 forming maltose
what is a product of a condensation reaction ?
water
what do fructose + glucose make ?
sucrose
what type of sugar is sucrose ?
a non reducing sugar
what does galactose + glucose make ?
lactose
what are pentose monosaccharides ?
sugars which contain 5 carbon atoms
give 2 examples of a pentose monosaccharide ?
ribose
deoxyribose
where is ribose present ?
RNA nucleotides
where is deoxyribose found ?
DNA nucleotides
water is a polar molecule, what does this mean ?
it has regions of positivity and negativity
where are the regions of positivity in a water molecule ?
the hydrogen atoms with a + charge
where are the regions of negativity in a water molecule ?
the oxygen atom
why do polar molecules interact with each other ?
the positive and negative regions attract each other
how to hydrogen bonds form between water molecules ?
the water molecules attract each other forming hydrogen bonds
what are hydrogen bonds ?
bonds which form between molecules
they are weak but occur in high numbers
why does water have a high boiling point and is liquid at room temperature ?
- they move around so constantly make and break hydrogen bonds
- it takes a lot of energy to increase the temperature and turn water to gas because of this
why is water less dense when solid ?
- it turns to ice when frozen
- the polar nature of water molecules means water makes 4 hydrogen bonds to other molecules forming a spaced out lattice structure which is rigid and open
why is water being less dense when solid a good thing ?
it creates a good habitat
it insulated water below
what is cohesion ?
when molecules are attracted to each other
how are water molecules cohesive ?
their polar nature
how is water being cohesive a good thing ?
- it makes it easy to flow
- it helps plants draw water up their roots
- helps when drinking up a straw
how does water get a skin of surface tension ?
- the molecules are more cohesive to each other than air
- the surface of water molecules contract resisting the force
what does adhesion mean ?
molecules are attracted to other materials
water molecules are attracted to other materials, how is this helpful ?
water is attracted to the sides of xylem vessels
water can act as a solvent, how is this helpful ?
many solutes in an organism can be dissolved, e.g proteins/amino acids
molecules in blood plasma can be dissolved
helps to transport dissolved compounds in and out of cells
water is a solvent and a polar molecule, what does this mean ?
anything polar can dissolve in it
anything polar can dissolve in water, why is this helpful ?
cellular reactions can take place in a solution
how can water help dissolve things (biological ionic reactions) ?
it is polar so the slight + end attracts the - ion and the slight - end attracts the + ion so ions can fully dissolve in water
water has a high specific heat capacity, what does this mean ?
it takes a lot of energy to raise 1 gram of it by 1 degree celsius
how is water having a high specific heat capacity helpful ?
- if doesn’t change state or temperature
- it provides a stable environment and a good habitat
- it acts as a coolant as it helps to buffer temperature changes during reactions in cells
- it provides a stable temperature for enzyme controlled reactions
water has a high latent heat of vaporization what does this mean ?
it takes a lot of energy to break all the hydrogen bonds between the molecules for it to go from a liquid to a gas (takes lots of energy)
why is water having a high latent heat of vaporization helpful ?
it can be used as a cooling mechanism , e.g sweating
why is water having a high latent heat of vaporization helpful ?
it can be used as a cooling mechanism , e.g sweating
what are peptides
polymers made up of amino acid molecule s
what are proteins
consist of one or more polypeptides arranged as macromolecules with specific biological functions
what elements to proteins have ?
carbon
hydrogen
oxygen
nitrogen
what are amino acids structure ?
basic structure - have an amine group
r group
carboxylic acid group
how many amino acids are found in cells ?
20
how many non essential amino acids are there ?
5
how many essential amino acids are there ?
9
how many conditionally essential amino acids are there ?
6
what is the synthesis of peptides ?
amino acids join when amine and carboxylic acid groups connect to the central carbon atom
what is the synthesis of peptides ?
amino acids join when amine and carboxylic acid groups connect to the central carbon atom
how exactly are proteins synthesized
hydroxyl in carboxylic acid group of one amino acid reacts with a hydrogen in the amine group of another amino acid
what bonds form between amino acids ?
peptide bonds
what kind of reaction happens between amino acids ?
condensation reaction
what is produced as a result of amino acids joining together ?
water
what kind of compound is 2 amino acids joined together called ?
dipeptic compound
what forms when many amino acids are joined together by peptide bonds ?
polypeptide
how is the reaction of amino acid joining together (peptide bonds) catalysed ?
enzyme peptidyl transferase which is present in ribosomes
how do different proteins differ from each other ?
different r groups of amino acids which make up a protein interact, forming different types of bonds which fold polypeptides into proteins
different sequence of amino acids = different structures = different shapes
why are proteins specific shapes ?
they carry out specific functions in living organisms
what are the different levels of protein. structures ?
primary
secondary
tertiary
quaternary
what is the primary structure in proteins ?
it is the sequence in which amino acids are joined
only peptide bonds involved
directed by information carried in dna
particular amino acids in a sequence influences how the polypeptides told to give the protein it’s final shape = determines function
what is the secondary protein structure ?
oxygen, hydrogen, nitrogen atoms of basic structure interact forming hydrogen bonds which pull the amino acid unto different shapes
what 2 different shapes do the polypeptides make in secondary structure ?
alpha helix
beta pleated sheet
what is the tertiary structure ?
- folding of a protein into its final shape
- coiling/folding of sections of proteins in their secondary structure brings r groups of different amino acids closer together to interact and fold more
what interactions /bonds are involved in the tertiary structure ?
- hydrophobic / hydrophilic interactions
- hydrogen bonds
- ionic bonds
- disulfide bonds
what is the quaternary protein structure ?
- results from the association of 2 or more proteins called subunits
- interactions between subunits are the same as the territory structure except they are between individual molecules
give examples of proteins which are in the quaternary structure ?
hormones
enzymes
how do hydrophobic and hydrophilic interactions in the quaternary structure occur ?
- proteins are assembled in an aqueous environment
- the way a protein fold depends on whether the r groups are hydrophilic or hydrophobic
- hydrophilic groups are on the outside
- hydrophobic groups are on the inside
how are peptides broken down ?
- protease enzymes reverse the reaction - turning peptides back into their amino acids
what type of reaction breaks proteins down ?
- hydrolysis reaction -
water added
what are globular proteins ?
- compact, soluble in water usually spherical
how do globular proteins form ?
when proteins fold into their tertiary structures
hydrophobic r groups are kept away from aqueous environment
hydrophilic r groups are on outside as they are soluble in water
what are globular proteins used for ?
regulating processes needed for life such as chemical reactions
give 3 examples of globular proteins ?
- insulin
- haemoglobin
- protease
what is the function of insulin ?
regulates blood concentration
hormone that fits into specific receptors in cell surface membrane
what is the function of insulin ?
regulates blood concentration
hormone that fits into specific receptors in cell surface membrane
what are features of insulin
soluble
precise shape
what are conjugated proteins ?
globular proteins which constrain a non protein prosthetic group
what are proteins without a prosthetic group known as ?
simple proteins
give examples of a conjugated protein ?
haemoglobin
lipoprotein
glycoprotein
lipid + protein
lipoprotein
carbohydrate + protein
glycoprotein
what is the structure of haemoglobin ?
quaternary protein made from 4 polypeptides - 2 alpha + 2 beta subunits
- each subunit has prosthetic haem group
how is haemoglobin structured to help it carry oxygen around the body ?
the iron ion in the haem group can combine reversibly with oxygen
what is the structure of catalase ?
quaternary protein containing 4 haem prosthetic groups
presence of iron II ions in prosthetic groups allow catalase to interact with hydrogen peroxide + speed up its breakdown
what does catalase do in terms of hydrogen peroxide ?
hydrogen peroxide is damaging to cells and a common byproduct of metabolism - catalase helps to break this down to make sure cell damage doesn’t occur
what is a fibrous protein ?
organized strong long molecules which aren’t folded into complex 3-D shapes
how are fibrous proteins formed ?
from long insoluble molecules due to presence of high proportion of amino acids with hydrophobic r groups
what is the structure of fibrous proteins like ?
contains limited range of amino acids with small r groups
amino acid sequence is in primary structure and repetitive
give 3 examples of fibrous proteins ?
keratin
elastin
collagen
where is keratin found ?
in nails skin and hair
describe the structure of keratin ?
has a large proportion of sulfur containing amino acid cysteine - strong disulfide bones
what determines keratins flexibility ?
the number of disulfide bonds present
where is elastin found ?
elastic fibres present in :
blood vessels
alveoli in lungs
what does elastin do ?
gives structures flexibility but so they can return to their normal size
describe the structure of elastin ?
- quaternary protein made from stretchy molecules called topoelastin
what stretchy molecules are elastin made from ?
tropoelastin
what is collagen ?
connective tissue found in skin tendons ligaments and the nervous system
how is collagen formed ?
made up of 3 polypeptides wound together
describe the structure of collagen !
rope like structure
flexible
when is elastin formed ?
when multiple tropoelastin molecules aggregate via interactions between hydrophobic areas
why can elastin stretch and recoil ?
tropoelastin molecules contain hydrophobic and lysine rich areas
how is the structure of elastin stabilized ?
by cross linking covalent bonds involving lysine
what shape does collagen make
triple helix
what shape does collagen make
triple helix
how does tropocollagen form ?
many hydrogen bonds form between polypeptide chains forming long quaternary proteins with staggered ends
these proteins join end to end
how is collagen strong ?
tropocollagen cross links
what elements are found in cholesterol ?
H, C, O, N
what elements are found in ATP
H C O N P
how is water a good solvent ?
- medium for metabolic reactions
- transport
- organisms can take in nitrate ions to help them build proteins
which processes involve ester bonds ?
synthesis of triglycerides and polynucleotides
what bond holds alpha glucose and fructose together
1-6 glycosidic bond
state a physical property of glucose that allows it to be easily physically transported in the bloodstream
- it’s soluble in water
how are glucose and cholesterol structurally similar
- both contain carbon
- both have OH groups /hydroxyl groups
state similarities between lactose and maltose
- both contain 1-4 glycosidic bonds
- both have 2 6 membered rings
give differences between lactose and maltose
- lactose has b glucose
- lactose forms b glucose glycosidic bonds
- sugars in lactose are flipped
- maltose contains a glucose
- both monomers in maltose are the same direction
why do mammals store glycogen instead of glucose
- glycogen is insoluble = doesn’t effect water potential
- glycogen is metabolically inactive
- glycogen stores lots of energy
how do lipids suit their role as energy storage molecules in plants and animals
- fats have more c-c bonds / c-h bonds
- fats are energy rich
- more energy stored in less space
- don’t affect water potential of cell
- fatty acids are long carbon chains that can be broken down to release acetyl groups
- animal fats are saturated /harder = role in protection and insulation
why are triglycerides with less hydrogen atoms have higher melting points ?
- more double bonds
- less saturated
- so lower melting point
why do lipids provide buoyancy
less dense than protein
describe how the structure of llama haemoglobin is different from that of a camel haemoglobin *refer to 4 levels of protein structure
Primary structure =
- different amino acid sequence
- 1 amino acid changed
Secondary structure =
- amino acid could cause change to secondary structure
- initial coiling/folding of polypeptide chain (a helix / beta pleated sheet, h bonding)
Tertiary structure
- amino acid could change this
- further coiling of secondary structure
- (ionic bonding, disulphide bonds, hydrophilic/hydrophobic bonds )
- 3-D
Quaternary structure
- not changed by amino acid
- alpha and beta sub-units are still able to form haemoglobin in camel and llama
what are polymers composed of
several monomers that are similar in structure
if a molecule is more soluble in water what does this suggest about its amino acid r group structure
it has higher polarity
