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MPW biology > 2.1.2 Biological molecules > Flashcards

2.1.2 Biological molecules Flashcards

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1
Q

what is water comprised off, what is its formula and ratio?

A

Oxygen and Hydrogen
H2O
2 H : 1 O

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2
Q

how would you descrive the distribution of charge in a water moelcule

A

an uneven distribution of charge between delta -ve oxygen and delta +ve hydrogen

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3
Q

what is the sign for delta?

A

𝛿

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4
Q

why is the charge described as uneven?

A

it is due to the pairs of electrons in each of the oxygen-hydrogen covalent bnds is not equally shared, as the electrons are more stronhly attraced to the oxygen atonms nucleaus than the hydrogen atoms nucleas

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5
Q

Polar definition

A

Molecules that have an uneven distribution of charge are reffered to as polar

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6
Q

Draw a diagram of a water moeclule, showing the uneven distribution of charge

A
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7
Q

what bond is present IN water molecules

A

Covalent bonds

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8
Q

what bond is present BETWEEN water molecules

A

Hydrogen bonds

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9
Q

why are water moleules attracted to each other?

A

The delta -ve oxygen from one water moelucle will be attracted to a delta +ve hydorgen from another water moelcule

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10
Q

other than water, what other polar groups are there?

A

Hydroxyl, amine and carbonyl

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11
Q

draw a fiagram of several water moleules, showing the partial charges and the hydrogen bonds

A
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12
Q

are polar moleucles soulbule or insoaluble and why?

A

Soluble, becuase water molecules will be attracted to, and will for hydrogen bonds with their polar groups

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13
Q

what is cohesion

A

when a hydrogen bond forms between to water molecules

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14
Q

what is adhesion

A

when a water moelcules and a different type of polar molecules for hydrogen bonds

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15
Q

can hydrogen form between two polar moleucles when neither are water?

A

yes, the same exact thing happens, and example would be two celluose molecules

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16
Q

what is the biological word for polar and water-soluble moleulces?

A

hydrophilic

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17
Q

hydrophilic deffinition

A

the physical properties of a molecules which attracts water molecules

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18
Q

are non-polar moelcuels soluble in water and why?

A

no, they are described as hydrophobic measning they repel water, this is due to the fact they have an even distribution of charge across the moelcules, so they cannot form partial chrages, therfore cannot form hydrogen bonds with water. An example of this is lipids

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19
Q

There are 8 main properties of water you must know what are they?

A

excellent solvent

effective thermal buffer

high latent heat of vaporisation

low density of ice compared to liquid water

choesion between water molecules

high surface tension

incompressibe

transparent

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20
Q

why is transparancy an important property of water?

A

it allows light water to pass through water, however its ability to do so depends on the wavelength of light.

this is especially important in aquatic plants and other photoynthetic oganisms which rely on ligh energy to drive photosynthesis (which produces glucose)

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21
Q

why is it good for water to be incompressible?

A

as water is a liquid, it is incompressible meaning it cannot be forced to decrease in volume.

this is important in insects, which have hydrostatic skeleton to supoort their body.

in plants, cell become turgid when the voume of water in the cell cretes pressure exerted on the cell wall, this is called cell turgor which is vital in enabling the leaves of a plant to be held up to intercept sunlight.

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22
Q

why is it good for water to have high surface tension?

A

hydrogen bonding from the surface wawter molecules to teh water moleucles below them cretes high surcace tenion, and the water on the top acts a a ‘skin’

this is important becuse small animals such as pnd skaters can move across the surface without breaking through.

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23
Q

why is it good for water to have cohesion between molecules?

A

water mnolcecules stick togetrher wia hyfrogen bonding. this allows waterto for strong, continuous colums withing a vessel/tube.

These colums have high tensile strength due to the high number of hydrogen bonds between the molecules.

liquids within a vessel will flow from one region to another due to gravity or a hydrostatic pressure difference via mass flow

Effecttive transport mediumn

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24
Q

why is it good that ice is less dense than water

A

this is due to the fact that water molecules forms a regular semi crystaline structure, with stable intermolecular hydrogen bonds, with the moleucles held far apart from each other.

as ice is less dense than water, ice floats on the surface of water.

Ice on the surace of water insulates the water below, reducing the chances the lower regions freeze. Therefore most aquatic organsism can surviuve even if the upper layers freeze, hence this property creates a stable environment for many species.

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25
Q

why is it good water has a high latent heat of vaporisation

A

at rtp water is a liquid due to the many hydrogen bonds which holds the moelcuesl very close togethre.

As of this lots of energy input is needed in order to xcayse liquid water to change to a gas state.

This is due to the numerous higydrogen bonds which need to be broken

This means when water evaporates it is an effective cooling method since it will take lots of energy away from the body when it turns to a gas. Hence water is acting as a coolant

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26
Q

why is it good for water be an effective thermal buffer?

A

water has a high specific heat capacity, meanign it takes lots of energy to increase by 1 degree.

this is due to the numerous hydrogen bonds requiring lots of energy to break.

This means that the temperature of water is very stable.

This is important in cells, since enzymes have a narrow optimum temperature range, and in ponds/lakes where there is a thermostable habitat that doesnt fluctuate.

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27
Q

why is it good water is an excellent solvent

A

water moelcules are polar, ie there is an unven distrivution of charge between the delta -ve oxygen and delta +ve hydrogen. As of this water molecules are able to form hydrogen bonds with otherpolar molecules and can interact with ions.

Water mpolecules are strongly attracted to a complety surround the moelcecule or ion of a soluble ions so they become dispersed and become dissolved.

This is good as molecules and ions can dissloved in things such as blood plasma for transportation

dilution of toxic substances such an ammonia

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28
Q

what is a condensation reaction?

A

a reaction is which two monomers are joinded together, forming a new bond, and a molecules of water is released during the reaction

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29
Q

what is a hydrolysis reaction

A

a reaction is which a molecule of water is used to break a bond.

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30
Q

are condesnation and hydrolysis reactions enzyme-catalysed?

A

yes

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31
Q

what is an enzyme which catalyses a condensation reaction called?

A

there is not a general name for these enzymes.

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32
Q

what is an enzyme which catalyses a hydrolysis reaction called?

A

hydrolytic enzyme

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33
Q

what elements are present in carbohydratres?

A

C, H and O

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34
Q

what elements are present in lipids?

A

C, H and O (Phospholipids contain P)

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35
Q

what elements are present in proteins?

A

C, H, O, N and S

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36
Q

what elements are present in nucleic acids?

A

C, H, O, N and P

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37
Q

what is a carbohydratre?

A

Biological moleuces whcih contain only the elements carbon, hydrogen, and oxygen, where there are twice as many hydrogen atoms than oxygen atoms

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38
Q

what is the carbohydrate general formula?

A

CX(H2O)Y

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39
Q

What is the simplest form of a carbohydrate called? and give 2 example

A

Monosaccharide

fructose

glucose

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40
Q

what is it called when two monosaccharides are bonded together in a condensation reaction? and what is the bond between the molecules called?

A

disaccharide is formed

glycosidic bond

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41
Q

what is the bond in carbohydrates called?

A

Glycosidic bond

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42
Q

what are three or more monosacchardies bonded together called?

A

polysaccharide

they are bonded into a long chain via glysocidic bonds

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43
Q

what is a hexose sugar?

A

a sugar with 6 carbons

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44
Q

what type of sugar is glucose

A

a hexose sugar

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45
Q

what is the molecular formula for glucose

A

C6H12O6

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46
Q

What are the two types of glucose and how do you remember where the hydroxyl (-OH) group is on the carbon 1?

A

α-glucose = Below

β-glucose = Above

Alpha

Below

Beta

Above

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47
Q

what is the name of the structual variants of molecules?

A

isomers

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48
Q

Draw α-glucose

A
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49
Q

draw β-glucose

A
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50
Q

what are the properties of glucose? and its main role?

A

they contain a polar hyroxyl group (-OH), meaning the can dissolve in water and form hydrogen bonds.

thhis is good so it can dissolve in blood plasma and be transported around the body

its main role is as an energy source is areobic respirtaion where is is broken down and oxidised to release energy

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51
Q

What is a pentose sugar?

A

a sugar with 5 carbons

52
Q

what is ribose and can you draw a picture?

A

a 5 carbon sugar (pentose). Ribose is part of the structure of an rna nucleotide andd part of the strucutre of an atp molecule

53
Q

what is deoxyribose and can you draw a picture?

A

a 5 carbon sugar (pentose). Deoxyribose is part of the strucure of a DNA nucleotide.

54
Q

what is the difference between ribose and deoxyribose?

A

deoxyribose has one less oxygen atom than ribose on the carbon 2 of the pentose sugar.

55
Q
  1. what is a glycodidic bond?
  2. When is it formed?
  3. What is its side product?
  4. where does it occur in a carbohydrate?
  5. how are disaccharide and polysacharides formed?
A
  1. a covalent bond between two monosaccharides.
  2. formed during a condensation reaction.
  3. A water molecule is formed as a side product. This is becuase two hydrogen atoms and one oxygen atom is removed from the monmosacharides, which join together to form water.
  4. between a hydroxyl from one moonosaccharide and a hydroxyl group from another monosaccharide
  5. they are formed by the joining of two or more monocsacchardies via glycosidic bonds
56
Q

what are the two monosacharide in maltose, and can you draw it with labels? and what is the bond called?

A

2 x α-glucose

α-1,4-glycosidic bond

57
Q

what is sucrose?,what are the two monosacharide in sucrose, and can you draw it with labels? and what is the bond called?

A

a disaccharide consisting of 1 α-glucose and 1 β-fructose

α,β-1,2-glycosidic bond

58
Q

what is lactose?,what are the two monosacharide in lactose, and can you draw it with labels? and what is the bond called?

A

a disaccharide consiting of β‐galactose + β(or α)–glucose, with the second sugar staggered or flipped over compared to the first

in the case of: β-1,4-glycosidic bond

59
Q

what is cellobiose?,what are the two monosacharide in cellobiose, and can you draw it with labels? and what is the bond called?

A

a disaccharide consiting of either 2 x β-glucose, where the seconda sugar is flipped over by 180 degrees

the bond is β-1,4-glycosidic bond

60
Q

what is needed when breaking a glycosidic bond?

A

water, specifically the atoms of a water moelecules which a reequired to reform the two hydorxyl groups which has previously undergone condensation to form the glycosidic bond.

61
Q

What are three examples of polysaccharides you must know?

A

Starch

Glycogen

Cellulose

62
Q

what is a lipid?

A

a non-polar hydrophobic compound, mostly made up of carbon and hydrogen atoms, with small proportions of oxygen.

63
Q

are lipids water soluble? if no, what do you think they are soluble in?

A

no they are not soluble in water, this is becuase the distribution of charge across the lipid is very even, so cant form partial charges, meaning no hydrogen bonds can form.

HOWEVER

lipiids are soluble in organic solventss such as benzene, as its also non-polar.

64
Q

what is the difference between a fat and an oil? plus give examples

A

fat = a lipid which is solid at room temperature, such assubcutaneous fats stored under the skin

oil = a lipid which is a liquid at room temperature, such as oil stored in sunflower seeds

65
Q

are lipids polymers?

A

NO! as they do not consist of a chain of specific repeating monomer subunits.

However

They are usually very large and complex moleucles (They are called Macromolecules)

66
Q

what is a fatty acid?

A

a carboxyl group (-COOH) attached to a hydrocarbon chain

They are a type of carboxylic acid

67
Q

Saturated fatty acids description, and where are they present

A

Saturated = all carbon atoms in the chain form the maximum bnumber of bonds with hydrogen atoms (NO cabon=carbon double bonds)

Straight in shape therefore NO kinks

Animals lipids often contain saturated fatty acids, this is becuause the hydrocarbon chains are straight, saturated fatty acids can pack closely together, resulting in lipids which are solids at rtp

68
Q

why are solid fats saturated?

A

Animals lipids often contain saturated fatty acids, this is becuause the hydrocarbon chains are straight, saturated fatty acids can pack closely together, resulting in lipids which are solids at rtp

69
Q

draw a saturated fatty acid

A
70
Q

what is an unsatuirated fatty acids? and what are the two types? kinks?

A

a fatty acid that contains at least one carbon-carbon double bond.

Monounsdaturated fatty acid = one carbon-carbon double bond, which has only one kink

Polyunsaturasted fatty acid = 2 or more carbon-carbon double bonds, with more than one kink (these are typically found in plants)

The kinks prevent the fatty acid chains from packing tightly together, therefore resuklting in a lipid that is a liquid at room temperature.

71
Q

how to work out if a lipid is saturated or unsaturated

A

excluding the -COOH, a saturated fatty acid will have double the number of ( H + 1)compared to C atoms.

For eacgh c=c double bond present, 2 H atoms are lost

72
Q

what is glycerol?

A

an alcohol, ie it contain a hydorxyl (-OH)

each hydroxyl group reacts in a condensation reaction with the hydroxyl from the fatty acid chain, therfore this reaction occurs threee time unless its a phospholipid then it occurs twice

73
Q

what is a triglyceride, what is the bond, and what is its condensation reaction called ?

A

1 x glycerol + 3x fatty acids

3 x ester bonds

esterification

74
Q

how is an ester bond broken? what are the enzymes which catalyse this reaction?

A

hydrolysis by adding water to break the ester bonds

catalysed by lipase enzymes

75
Q

draw a triglyceride with labels

A
76
Q

Give 5 properties of lipids

A
  1. Long term energy storage - due to its being very compacts and conmtains many energy rich C-H and C-C bonds, so lots of energy can be sotred in a small place
  2. Thermal insulation
  3. Flotation
  4. cushioning of internal organs
  5. insoluble in water - doesnt effect the osmotic balcance/ water potential in cells.
77
Q

what is a phospholipid?

A

similar to triglyceride, but instead of 3 x fatty acids, there is 2x fatty acid and 1x phosphate group

78
Q

can you draw a phospholipid?

A
79
Q

what is different about a phospholipid than a triglyceride?

A

part of the phospholpid, the phosphate group is negatively cahrge, meainng it is water soluble and can for hydrogen bonds with water. this is described as a hydrophilic head (includes glycerol and phospahte group)

HOWEVER

the two fatty acids chains dont cahnge therefore they are non-polar and cant dissolve on in water, creating hydrophic tails, so they repel water molecules

80
Q

what occurs due to the hydrophilic head and the hydrophobic tails?

A

A bilayer can form when placed in water.

there are two layers of phospholipds, where the fatty acid tails point inwards creating a hydrophobic core free of water, whereas the hydrophilic phosphate heads lie outwards, where they can interact with water.

81
Q

what is the basis of all biologuical membranes and why?

A

the phospholipid bilayer, becuase it is partially permerbale and only allows small and lipid soluble molecules free, whereas polar and ions are unable to passs through

82
Q

give a use of muliple layer of membrane

A

electrical insulatuion, ie in the myelin sheath around the axon of a neurone

83
Q

what is a sterol? structure?

A

steroid alcohols.

very complex structure based on four fused carbon rings

they have ahydrophilic hydroxyl group, howver the rest of the molecules is hydrophobic, meainng their porperties are similar to phospholipids

84
Q

give an example of a sterol, and state its properties

A

Cholesterol - a principle sterol in our bodies

  1. Its a constituent of the plasma membra, wher is fits between the phospholipds, its job is to regulate the membranse fluidity
  2. Precursor in the synthesis of vitamin D
  3. A precursor in the synthesis of steroid hormones, suihc as testosterone.
85
Q

draw me and label a general amino acid

A
86
Q

what does the R stand for?

A

a variable group, as there aer over 20 different amino acids, it is easy just to put R as it can b e interchangable for each amino acid

They vary is size and chemical properties, and may even contain different elements.

87
Q

what in the central carbon in an amino acid called?

A

alpha carbon

88
Q

how many different amino acids are there?

A

20

89
Q

what is the only amino acid containing a sulfur atom?

A

Cysteine, its R group is -RH, therfore is can form disulfide bonds.

90
Q

what is the difference between essential and non-essential amino acids?

A

essential amino acids- they cannot be made in the body, and can only be obtained via our diet

non-essential amino acids- these can be made in out body from essential amino acids, in a process called transamination.

91
Q

what is the bond in polypeptides called?

A

peptide bond

92
Q

how does a peptide bond form? what is the reaction called? bi-products?

A

a reaction between the amine of one amino acid and the carboxyl from another amino acid

condensation reaction

water

93
Q

draw a simple dipeptide and clearly label the peptide bond

A
94
Q

how are amino acids assembled in the cells?

A

ribosomes join together thae amino acids, into a specific sequence determined by the mRNA, in a process called translation.

95
Q

what enzyme catalyses translation?

A

peptidyl transferase.

96
Q

what is the name of many amino acids joined together with peptide bonds when forming a long unbranched chain?

A

A polypeptide

97
Q

what is a protein

A

One or more polypeptides which have a specific shape and biological function

98
Q

how do you calculate the number of different polypeptides?

A

20n

i.e pentapeptide = 205 = 3.2 x 106

99
Q

what is the name of the enzymes which catalyses polypeptides back into amino acids?

A

protease enzymes

100
Q

Primary structure of proteins

A

The specific sequence of amino acids, bonded together by peptide bonds

101
Q

how is the primary structure of proteins determined?

A

its determined by the order od DNA bases in the genes which encodes that protein, in short its genetically determined

102
Q

Secondary structure of proteins

A

chain coil - alpha helix

fold back - beta pleated sheets.

The only bonding present here is intramolecular hydrogen bonding

(between delta -ve oxygen and delta +ve hjydrogen)

DONT FORGET

some regions may not adopt either of these strucure but instead form a random coil.

103
Q

how is the secondary structure of proteins determined

A

its the result of further folding and hydrogen bonding at regions along the amino acid sequence

104
Q

Teritiary structure of proteins

A

Hydrophobic interactions - the intercation between non-polar R groups interacting with only one another, and excluding water and other polar R groups. ie creating a hydrophobic core inglobular proteins

Hydrophilic interactions - water soluble R groups will be attracted to watcer and to eaxh other, leading to the formation of hydrogen bonds between delta +ve and delta -ve atoms. ie creating the hydrophilic surface in globular proteins. Creates good solubility

Disulfide bonds - only occur when there are two sulfur atoms present in the R groups, which can only happend if two cysteine amino acids are present in different region of the polypeptide chains. (Only seen in proteins secreted out of the cell)

ionic bonding - these are the stong electrosation attractions between a positive and negative ion. Normallu occurs, when one R group loses a hydrogen ion, and another R group gain a hydrogen ion. if pH is changed, the shift in hydrogen ions can negatively affect the ionic bonding.

105
Q

how is the teritary structure of proteins determined?

A

by futher folding of the polypeptides into its 3D shape. This involves various types of bondings between tbe R groups of amino acids in the polypeptide chain.

these being: hydrophobic interaction, hydrophilic interactions, disulphide bonds, ionic bonds and hydrogen bonds.

106
Q

Quaternary structure of proteins

A

only some proteins

same bonding as the tertary strucute

Occurs when more than 1 polypeptide chains joined together to form the final 3D shape.

107
Q

what is a globular protein?

A

proteins in which the polypeptide chain(s) re folded into a compact, roughly spherical.

The hydorphobic R groups are burried in the core of the proteins, hence the name hydrophic core, and the hydrophilic R groups are mostly exposed on the surface of the protein, therefore globular proteins have good solubility in water.

many of them are conjugated, meaning they have a permenantly attached prosthetic group that is essentialy to carry out their function.

108
Q

are globular proteins soluble?

A

The hydorphobic R groups are burried in the core of the proteins, hence the name hydrophic core, and the hydrophilic R groups are mostly exposed on the surface of the protein, therefore globular proteins have good solubility in water.

109
Q

what are 3 examples of globular proteins?

A
  1. Insulin
  2. Catalase
  3. Haemoglobin
110
Q

Describe the function, structure and properties of INSULIN

A

Conjugated Protein

Function: A hromone which control the blood glucose levels via cell signalling. insulin binds to specific complementary receptors on the plasma membrane of the lvier and muscle cells triggering them to absobed the excess glucose

Structure: Insulins tertiary structure has a very specific 3D strucutre, therefore the polypeptide chain must fold the same way for every single insulin protein, this is important as inslin is complementary and wouldnt be able to work if its hsape want corrrect.

Insluin has good solubility which is achieved by the hydrophilic R group surface of the globular protein

111
Q

Describe the function, structure and properties of CATALASE

A

CONJUGATED PROTEIN

Function: an enzyme which acts as a biological catalyst in the process of breaking down hydrogen peroxide (a toxic waste product of cellular metabolism) into oxygen and water

structure: there is more than one polypeptide in the quaternary structure, also it is a conjugated protein meaning it has a permentant prothetic group attached. In this case the prothetic groups are haem groups, which contain fe2+ ions.

112
Q

Describe the function, structure and properties of HAEMOGLOBIN

A

Found in erythrocytes (red blood cells), whwerew is role is to reversibly combine with oxygen and hence carry oxygen in the blood from he lungs to repireing tissue.

structure: there are 4 polypeptide chains prsent in the quaternary structure, thse being 2x alpha-globin and 2x beta-globin
properties: high solubility do itr can redily dissolve in the cytoplasm of erytherocytes, which is achieved by the hydrophilic R group surface of the globular protein
conjugated: like catalase, it has prothetic groups of haem, each polypeptide chain has one heam group each, therefore there are 4 haem groups, an there is an Fe2+ ion in each haem group.

one molecule of oxygen can bind to one haem group therfore one haemoglobin molecule can carry up to 4 oxygen molecules each.

113
Q

what is a fibrous protein?

A

elongated proteins, where the polypeptide chains do not fold up into a sperical shape.

they tend to be very long and insoluble, due to their massive size and presence of many amino acids with hydrophobic R groupos exposed to the surface.

High tensile strength, due to the forming of long ‘rope-like structure’

Metabolically unreactive

Flexible

less variety in amino acid types in their primary strucutre, and thier primary structure is quite repetative.

114
Q

properties and functions of collagen

A

Fibrous protein

very high tensile strength, insoluble but flexible

found in the connective tissue of skin, ligaments and tendons

high tensile strength due to the strucutre, where three polypeptides wound around one another in a rop like strucure, also there are numerous molecules crossed lonked with many hydrogen bonds.

115
Q

properties and function of keratin

A

fibrous protein

insoluble, high tensile strength, relatively inflexible

present in hair and nails

contains a very high proportion of sulfur containg cystein in the primary structure, this allows for numerus disulfide bonds in the tertiary strucure, giving incresed stregth, but reduced flexiility in the protein.

116
Q

properties and functions of elastin

A

fibrous protein

stretchy (allows for the walls of the alveloi and artieries to expand and passively recoil to return to their orginal shape.

found in elastic fibres

Quaternary strucutre made up of many different TROPELASTIN POLYPEPTIDES cross linked to one another.

117
Q

test for proteins

A

Biuret reagent

sodium hydroxide solution mixed with copper sulfate solution

add it to the sample, if there is a colour change from pale blue to lilac/purple colour

118
Q

test for starch

A

add a few drops of iodine solution to the test sample, if the colour chanfges from yellow to blue/black, starch is present

119
Q

test for lipids

A

the sample should be mixed with equal volume of ethanol and water and shake, if lipids are present a milky white emulsion should form

120
Q

test for reducing sugars

A

Benedicts test ( alkalime copper (II) sulfate)

all mono and most disacharides are capable of donating electrons

add an equal volume of benedicts solution to the test sample, and heat at 80 degrees celcus for around 10 mins.

none: pale blue solution
little: green ppt
some: orange ppt
lots: brick red ppt

121
Q

test for non-reducing sugar

A

gives negative result to benedicts reagent.

non-reducing sugar can be hydrolysed into reducing sugars components

  1. boil in dilute HCl
  2. if before hydrolysation its negative, and then test positive after hydrolysation the conclusion is that a non-reducing sugar was present in the original sample.
122
Q

reagent test strips for reducing sugars

A

dipped in sample, and if there is a colour change it can be compared with colour chart giving an approximate concentration of reducing sugars.

123
Q

properties and strucutre of starch

A

energy storage polysaccharide

2 differnet alpha glucose polymers, amylose and amylopectin

can be readily hydrolysed by enzymes, releasing alpha glucose

starch is compact, very low solubility therefore doesnt effect osmotic potential.

124
Q

properties and structue of glycogen

A

energy storeage polyscacharide in animal and fungal cells.

alpha glucose polymer branched structure

1,4 and 1,6

lots of branching therefor very compact

Some coiling

branches mean quickly hydrolysed fior a quick release of glucose during areobic respiration

insolube, therfore doesnt effect osmotic balance

stored as glycogen granules

125
Q

properties and strucure of cellulose

A

beta-glucose

1,4 only

used in plant cell walls

linear, unbrached

each beta glucose is at flipped 180 degrees, creating a perfect straight chain, with no coiling

they bundle togerhter in parallel by many hydroge bonds, forming cellulose microfibrils which have an extremely high tensile strenth whilst remaining flexibile.

insolub;e, meaing they can be used as cell wall, as they ownt be dissolved bu water, its also unreactive so it wont weaken during internal metabolic reactions.

126
Q

amylopectin in starch properties

A

aplha glucose

1,4 and 1,6

same orientation

branched

some coiling

low solubility

starch grain

present in plant chloroplast

Energy storage

127
Q

amylose in starch properties

A

alpha-glucose

1,4 only

same orientation

linear

coiled

low solubility

starch grain

present in chlorplast

energy store

MPW biology (26 decks)

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