Biological molecules Flashcards
What are the units of the mole?
mol
what is a solvent?
The liquid that a solute is dissolved into to make a solution
Individual biological molecules that can be linked to form chains are called…
monomers
Which type of reaction take place every time a monomer undergoes polymerisation?
a condensation reaction
How many atoms of carbon-12 are found in 1 mole of carbon-12?
6.022 x 1023
Which polymer do many mononucleotides form?
Polynucleotides
Define a ‘molar solution’ (1 M)
A molar solution (1 M) is a solution that contains 1 mole of solute in every litre (dm3) of solution.
How else can 1 mol dm-3 be written?
1 mole per litre
1 Molar
1 M
Name the common biological monomers
mononucleotides (or just nucleotides)
monosaccharides
amino acids
Describe a hydrogen bond
When the positive charge of one polar molecule is attracted to the negative charge of another polar molecule.
How can we find the mass of 1 mole of a more complex molecule?
Look up the atomic masses of each element that make up the molecule and add them together.
The process of polymer formation from monomers is called…
polymerisation
a hydrolysis reaction requires…
the addition of water to separate a polymer into its monomers.
What is meant by metabolism?
All of the chemical reactions that are taking place in the human body
What is a solute?
The solid that is dissolved to make a solution
Name 3 common biological polymers
Polynucleotides
Polysaccharides
Polypeptides (proteins)
What is 6.022 x 1023 referred to as?
Avagadros Number
Avagadros Constant
The number of something in 1 mole
Describe a covalent bond
When atoms share a pair of electrons in their outer shell.
Which polymer do many monosaccharides form?
Polysaccharides
a condensation reaction releases…
a water molecule when monomers join
How else can 1 mole per litre be written?
1 mole dm-3
1 Molar
1 M
1 litre = _____ dm3
1 litre = 1 dm3
How many of something are there in 1 mole?
6.022 × 1023
Name the 3 types of bond that join biological molecules together
Covalent bonds
Ionic bonds
Hydrogen bonds
Long chains of monomer sub units are called…
polymers
Moles are used when talking about large numbers of substances such as…
Atoms
Molecules
What is a molecule?
When two or more atoms are chemically bonded together.
What is the mass of 1 mole of carbon?
12 g
Describe an ionic bond
When oppositely charge ions are attracted to one another e.g. Na+ and Cl-
What is an atom?
The smallest particle of a chemical element that can exist
How can we easily find the mass of 1 mole of an element?
Look up the atomic mass of the element on a periodic table.
Which polymer do many amino acids form?
Polypeptides (proteins)
Which type of reaction take place every time a polymer is broken down into monomers?
hydrolysis
name the molecule
unsaturated fatty acid
Name a biological molecule that contains nitrogen
protein/amino acids
DNA
RNA
ATP/ADP
NAD/NADP
nucleotide
define a monomer
smaller/repeating unit/molecule from which a larger molecule is made (polymer)
What monomers make up lactose?
galactose and glucose
name the bond between 2 monosaccarides
glycosidic
name the bond between fatty acids and glycerol
ester
An individual sugar molecule is called a…
monosaccharide
Name a structural polysaccharide
Cellulose (plant cell walls)
A 5 carbon sugar is called a…
pentose
What happens during hydrolysis
A water molecule is taken in to break down a chain of molecules.
A 4 carbon sugar is called a…
tetrose
Polysaccharides are large. This means that they are…
insoluble (will not dissolve)
When many monosaccharides join together, they form a…
polysaccharide
Which elements make up carbohydrates?
Carbon
Hydrogen
Oxygen
When 2 monosaccharides join together, they form a…
disaccharide
What happens during a condensation reaction?
A water molecule is released from the reacting molecules
How many covalent bonds does carbon make?
4
Which type of reaction takes place when two monosaccharides join together?
Condensation Reaction
A 3 carbon sugar is called a…
triose
A 6 carbon sugar is called a…
hexose
Name the bond that forms between two monosaccharides
Glycosidic bond
An individual biological molecule is called a…
monomer
Which type of reaction takes place when a disaccharide or polysaccharide is broken down?
Hydrolysis
Name 3 common disaccharides
Maltose (glucose + glucose)
Sucrose (glucose + fructose)
Lactose (glucose + galactose)
What is an isomer?
Molecules that have the same chemical formula but whose molecules are arranged differently.
Long chains of repeating molecules are called…
polymers
Glucose + Fructose –> _________
Glucose + Fructose –> Sucrose
The general chemical formula of a monosaccharide is…
(CH2O)n where n is the number of carbon atoms.
Glucose + Glucose –> _________
Glucose + Glucose –> Maltose
A 7 carbon sugar is called a…
heptose
A molecule containing carbon is called an…
organic molecule
Name 4 common hexose monomers
α-Glucose
β-Glucose
Galactose
Fructose
Name 2 common storage polysaccharides
Glycogen
Starch
Which 4 elements make up most biological molecules?
Carbon
Hydrogen
Oxygen
Nitrogen
Glucose + Galactose –> _________
Glucose + Galactose –> Lactose
Polysaccharides are used in cells for _____________ and ____________
Storage (energy)
Structure (cell walls)
name the monomer that makes up maltose
glucose
sucrose hydrolysis produces..
fructose and
glucose
How is starch related to its function?
- Helical/ spiral shape so compact;
- Large (molecule)/insoluble so osmotically inactive;
- Branched so glucose is (easily) released for respiration;
- Large (molecule) so cannot leave cell/cross cell-surface membrane;
How is the structure of cellulose suited to its function?
Long, straight/unbranched chains of β glucose;
Joined by hydrogen bonding;
To form (micro/macro)fibrils;
Provides rigidity/strength;
What other enzyme is required for the complete digestion of starch?
amylase and maltase
Give 2 differences between the structure of cellulose and glycogen
celluose molecules straight chains;glycogen branched
cellulose beta glucose;glycogen alpha glucose
celluose molecules straight chains; glycogen coiled
celluose has only 1, 4 glycosidic bonds; glycogen has 1,4 and 1,6 bonds
Desccribe and explain 2 features of starch that makes it a good storage molecule
coiled/helical making it compact
insoluble so does not affect the WP of cells
LArge so cant cross the cell membrane
Branched so more ends for enzyme action
test which tests for starch?
iodine
Describe how lactose is formed
glucose and galactose
join by condensation reaction
through a glycosidic bond
An individual sugar molecule is called a…
monosaccharide
What does it mean if a food sample turns benedicts solution this colour?
Low concentraiton of reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
Low concentraiton of reducing sugar is present
What is a reducing sugar?
A sugar that can give an electron to the Copper (II) Sulphate found in Benedict’s reagent to make it form a red Copper (I) Oxide precipitate.
How would you carry out a Benedict’s rest for a reducing sugar
- Add 2cm3 of the food sample to a test tube
- Add an equal volume of Benedict’s Reagent
- Heat the mixture in a boiling water bath for 5 minutes
- Observe colour change
What do we mean when we say that the Benedict’s Test for Reducing Sugars is ‘semi-quantitative’?
That the colour of the result can be used to estimate the approximate amount of reducing sugar in a sample
What does it mean if a food sample turns benedicts solution this colour?
No reducing sugar is present
What do the followign instructions describe a test for?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Non-Reducing Sugars
What does it mean if a food sample turns benedicts solution this colour?
Medium concentration of reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
High concentration of reducing sugar is present
What do we mean when we say that the Benedict’s Test for Reducing Sugars is ‘semi-quantitative’?
That the colour of the result can be used to estimate the approximate amount of reducing sugar in a sample
What does it mean if a food sample turns benedicts solution this colour?
No reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
Very low concentraiton of reducing sugar is present
What does this picture show?
The results of Benedict’s test according to the concentration of reducing sugar present
Which two reducing sugars are released when sucrose is hydrolysed?
Glucose
Fructose
What does it mean if a food sample turns benedicts solution this colour?
Medium concentration of reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
High concentration of reducing sugar is present
What is a reducing sugar?
A sugar that can give an electron to the Copper (II) Sulphate found in Benedict’s reagent to make it form a red Copper (I) Oxide precipitate.
What does this picture show?
The results of Benedict’s test according to the concentration of reducing sugar present
What does it mean if a food sample turns benedicts solution this colour?
Very low concentraiton of reducing sugar is present
Which two reducing sugars are released when sucrose is hydrolysed?
Glucose
Fructose
Name a disaccharide that is a non-reducing sugar
sucrose
What do the followign instructions describe a test for?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Non-Reducing Sugars
How would you carry out a Benedict’s rest for a reducing sugar
- Add 2cm3 of the food sample to a test tube
- Add an equal volume of Benedict’s Reagent
- Heat the mixture in a boiling water bath for 5 minutes
- Observe colour change
During a Non-Reducing sugar test why do we need to neutralise the food sample after heating it in acid?
Because Benedict’s reagent will not work in acidic conditions (ideally alkaline)
What do the following instructions describe a test for?
- Add 2cm3 of the food sample to a test tube
- Add an equal volume of Benedict’s Reagent
- Heat the mixture in a boiling water bath for 5 minutes
- Observe colour change
A Benedict’s Test for a Reducing Sugar
Which two reducing sugars are released when sucrose is hydrolysed?
Glucose
Fructose
What do the followign instructions describe a test for?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Non-Reducing Sugars
What is a Non-Reducing Sugar?
A sugar that is unable to give an electron to the Copper (II) Sulphate in Benedict’s Reagent so it is unable to form a red Copper (I) Oxide precipitate
What method would you use to produce different concentrations of sucrose from a concentrated sucrose solution?
serial dilution
Name 2 common disaccharides that are reducing sugars
Maltose
Lactose
The process of breaking a disaccharide up into 2 monosaccharides is called…
Hydrolysis
How would you test for a Non-Reducing Sugar?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Which types of sugars are all reducing sugars?
Monosaccharides
Name a disaccharide that is a non-reducing sugar
sucrose
How would you carry out a Benedict’s rest for a reducing sugar
- Add 2cm3 of the food sample to a test tube
- Add an equal volume of Benedict’s Reagent
- Heat the mixture in a boiling water bath for 5 minutes
- Observe colour change
What do the following instructions describe a test for?
- Add 2cm3 of the food sample to a test tube
- Add an equal volume of Benedict’s Reagent
- Heat the mixture in a boiling water bath for 5 minutes
- Observe colour change
A Benedict’s Test for a Reducing Sugar
During a Non-Reducing sugar test why do we need to neutralise the food sample after heating it in acid?
Because Benedict’s reagent will not work in acidic conditions (ideally alkaline)
What method would you use to produce different concentrations of sucrose from a concentrated sucrose solution?
serial dilution
Name 2 common disaccharides that are reducing sugars
Maltose
Lactose
The process of breaking a disaccharide up into 2 monosaccharides is called…
Hydrolysis
How would you test for a Non-Reducing Sugar?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Which types of sugars are all reducing sugars?
Monosaccharides
What is a Non-Reducing Sugar?
A sugar that is unable to give an electron to the Copper (II) Sulphate in Benedict’s Reagent so it is unable to form a red Copper (I) Oxide precipitate
What is a reducing sugar?
A sugar that can give an electron to the Copper (II) Sulphate found in Benedict’s reagent to make it form a red Copper (I) Oxide precipitate.
What does it mean if a food sample turns benedicts solution this colour?
Low concentraiton of reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
Low concentraiton of reducing sugar is present
What does it mean if a food sample turns benedicts solution this colour?
Very low concentraiton of reducing sugar is present
What does this picture show?
The results of Benedict’s test according to the concentration of reducing sugar present
What does this picture show?
The results of Benedict’s test according to the concentration of reducing sugar present
What does it mean if a food sample turns benedicts solution this colour?
Very low concentraiton of reducing sugar is present
What is a reducing sugar?
A sugar that can give an electron to the Copper (II) Sulphate found in Benedict’s reagent to make it form a red Copper (I) Oxide precipitate.
What is a reducing sugar?
A sugar that can give an electron to the Copper (II) Sulphate found in Benedict’s reagent to make it form a red Copper (I) Oxide precipitate.
What is a Non-Reducing Sugar?
A sugar that is unable to give an electron to the Copper (II) Sulphate in Benedict’s Reagent so it is unable to form a red Copper (I) Oxide precipitate
Which types of sugars are all reducing sugars?
Monosaccharides
How would you test for a Non-Reducing Sugar?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
The process of breaking a disaccharide up into 2 monosaccharides is called…
Hydrolysis
Name 2 common disaccharides that are reducing sugars
Maltose
Lactose
What method would you use to produce different concentrations of sucrose from a concentrated sucrose solution?
serial dilution
What method would you use to produce different concentrations of sucrose from a concentrated sucrose solution?
serial dilution
Name 2 common disaccharides that are reducing sugars
Maltose
Lactose
The process of breaking a disaccharide up into 2 monosaccharides is called…
Hydrolysis
How would you test for a Non-Reducing Sugar?
- Boil the sample with hydrochloric acid
- This will hydrolyse any disaccharide into 2 monosaccharides
- Cool solution and neutralise with sodium hydrogen carbonate
- Add Benedict’s Reagent and heat
- Observe colour change
Which types of sugars are all reducing sugars?
Monosaccharides
What is a Non-Reducing Sugar?
A sugar that is unable to give an electron to the Copper (II) Sulphate in Benedict’s Reagent so it is unable to form a red Copper (I) Oxide precipitate
