Molecular Building Blocks Flashcards
What are the basic building blocks in atoms
Carbon
Hydrogen
Oxygen
Nitrogen
Sulphur
Phosphate
What are macromolecules
Macromolecules are simple molecules such like sugars, lipids and amino acids bonded to form bigger complex molecules
What are some examples of macromolecules
Haemoglobin
DNA
Glycogen
Collagen
What are monosaccharides composed of
One hydroxyl group
If it is an aldose it will have an aldehyde group
If it is a ketose it will have a ketone group
They are usually a ring structure
How is a glycosidic bond formed
A glycosidic bond is formed by the OH of the hydroxyl group reacting with either a OH or NH group
What do O-glycosidic bonds form
Disaccharides
Oligosccharides
Polysaccharides
Where would you find an N-glycosidic bond
Nucleotides in DNA
What do disaccharides contain
2 monosaccharides which are joined by an O-glycosidic bond
What does an oligosaccharide contain
3 to 12 monosaccharides joined by O-glycosidic bonds
Where do oligosaccharides come from
They are either a product of digestion from a polysaccharide or part of a complex protein or lipid
How are polysaccharides formed
Thousands of monosaccharides bonded by O-glycosidic bonds
What is an example of a polysaccharide
Glycogen is a branched polysaccharide formed of glucose residues
What are nucleotides
Building blocks of DNA
What are nucleotides made up of
Nitrogenous base
Sugar
Phosphate
What are the bonds between the bases
Hydrogen bonds
What are the bonds between the phosphate and sugars molecules
Phosphodiester bonds
What are the sources of energy in nucleotides
Phosphate bonds
What is a triglyceride made up of
3 fatty acids bound to glycerol
What does unsaturated fatty acids contain that saturated fatty acids don’t
A double bond
How are amino acids linked together
Peptide bonds
What is a protein
A large polypeptide formed of 10s and 1000s amino acids
What is the function of a protein
The function of a protein depends solely on the structure of the protein
What is a primary structure of a protein
A linear sequence of amino acids
What are secondary structure of a protein
Alpha helix or beta pleated sheet which is formed due to H+ bonds between the amino acids which is determined by local interactions between side chains and the sequence of amino acids
What is the tertiary structure of a protein
A 3D conformation of a protein which can be changed by temperature of pH
What is the quaternary structure of a protein
A full 3D structure of a protein with multiple subunits
What are the different forces that can be found in protein structures
Van de waals forces
Hydrogen bonds
Hydrophobic forces
Ionic bonds
Disulphide bonds
What are van der waals forces
They are weak attractive/repulsive force between all atoms due to fluctuating electrical charge
What are hydrogen bonds
Interactions between polar groups
What are hydrophobic forces
As uncharged and non-polar side chains are repelled by water, hydrophobic side chains form tightly packed cores in the interior of proteins, excluding water molecules
What are ionic bonds
They are found between fully/partially charged groups
What are disulphide bonds
Very strong covalent bonds between sulphur atoms
What are amino acids
Building blocks of proteins
How many amino acids are there in total
20 amino acids
What are amino acids made up of
Amino acids are made up of carbon with amino group, carboxyl group and a specific side chain
What is the charge of an amino acid determined by
The charge is determined by its 3 components along with the pH of the environment
What does the side chain determine in an amino acid
The side chain determines polarity and so determines solubility and permeability
How is a peptide bond formed
Through a condensation reaction
What are properties of amino acids
Very stable
Cleaved by proteolytic enzymes
Can have partial double bonds
Flexibility around the C atoms
Usually one preferred conformation determined mainly by types of side chains and amino acid sequence
What is a catalyst
Provides an alternative reaction pathway with a lower activation energy
What is the function of a catalyst
A catalyst enables reactions to occur that otherwise would not be able to occur at physiological temperatures and conditions
They speed up reactions and provide a way to regulate the reaction
How do catalysts regulate reactions
They alter the concentrations of substrates, products, inhibitors and activators
The rate of reaction can also be regulated by modifying the enzyme itself through phosphorylation
What are isoenzymes
Enzymes that have a different structure and sequence but catalyse the same reaction
What are coenzyme
These are enzymes which in them self cannot catalyse a reaction but can help enzymes To do so, they bind with enzyme protein molecules to form active enzymes
What are simple sugars made up of
Carbon
Oxygen
Hydrogen
What are complex sugars made up of
Long chains of simple sugars bonded together
How many sugar molecules are in monosaccharides
1 sugar
How many sugar molecules are in disaccharides
2 sugars
How many sugars are there in oligosaccharides
3-9 sugars
How many sugar molecules are in polysaccharides
10+ sugars
What is the most important monosaccharide and why
Glucose
It is the main source of energy for the body and it is able to cross the blood brain barrier to nourish the brain
What is lactose made up of
Glucose and galactose
What is sucrose made up of
Glucose and fructose
What is maltose made up of
2 glucose molecules
What is glacto-oligosaccharides made up of
Long chains of galactose bonded together
What is a structural characteristic of polysaccharides
Branched
What is a common polysaccharide found in food
Starches
What is a characteristic of dietary fibres
They cannot be broken down by intestinal enzymes
What is the function of dietary fibres
They slow down absorption of simple sugars which helps to maintain blood glucose
They decrease constipation
Dietary fibres such as beta-glucan is good for heart health
What is a glycosidic bond
This a bond formed between two monosaccharides and how complex sugars are made
This bond happens between the OH of one molecule and H on the other molecule, this forms a water molecule which is removed and is known as a condensation reaction
How does an alpha-glycosidic and beta-glycosidic bond differ
The alpha-glycosidic done the molecules are lined up whereas in a beta-glycosidic bond the molecules are stacked on top of each other due to the different carbon molecules which are bonding
How can sugars be absorbed for use
The disaccharides, polysaccharides and oligosaccharides are broken down by enzymes in the digestive track into monosaccharides so they can be absorbed into the blood stream for use in the body
What enzyme breaks down most polysaccharides
Amylase
What breaks down lactose
Lactase
What breaks down sucrose
Sucrase
What breaks down maltose
Maltase
What is the structure of DNA and what is its function
Double stranded wound into an alpha helix
Found inside the nucleus
Which stores the genetic information of the cell
What is the structure of RNA and what is its function
RNA is a single stranded molecule found outside the nucleus
Which is involved in protein synthesis
How does DNA become a protein
DNA
Transcription
RNA
Translation
Protein
What are both DNA and RNA made up of
They are both polymers so are made up of long chains of monomers
What is the monomer of DNA and RNA
Nucleotide
What is the basis of a nucleotide
Sugar + nitrogenous base + phosphate group
What makes up a DNA nucleotide
Deoxyribose sugar + nitrogenous base + phosphate group
What nitrogenous bases can be found in DNA and what bonds to what
Adenine bonds with thymine
Guanine bonds with cytosine
What makes up an RNA nucleotide
Ribose sugar + nitrogenous base + phosphate group
What nitrogenous bases can be found in a RNA nucleotide and what bonds with what
Adenine bonds with uracil
Guanine bonds with cytosine
What is the bonds found between the nitrogenous base pairs and how many bonds between each
There are hydrogen bonds found between the nitrogenous bonds
Adenine to either thymine or uracil contains 2 hydrogen bonds
Guanine to cytosine contains 3 hydrogen bonds
What is the bond between the sugar and the phosphate group called
Phosphodiester bond
What are the 2 types of nitrogenous bases
Purines and pyrimidines
What are the differences between purines and pyrimidines
Purines have a double ring structure made up of a 6 carbon sugar with a 5 carbon sugar
Pyrimidines have a single ring structure made up of a 6 carbon sugar
What nitrogenous bases fall under the purines and which fall under pyrimidines
Purines are adenine and guanine
Pyrimidines are thymine, uracil and cytosine
What is a lipid
It is a macromolecule made up of mostly carbon and hydrogen
What are fatty acids made up of
Hydrocarbon chain and a functional carboxyl group
What does it mean if a fatty acid is saturated
This means that every single carbon is attached to and making the maximum amount of bonds it is able to make with hydrogen atoms
Why are saturated fatty acids solid at room temp
They are solid at room temp as they are saturated so form a linear unit which is able to stack tightly making them a solid at room temp
What is a monounsaturated fatty acid
This is a fatty acid that has 1 double bond present between 2 carbon atoms so it means that not all the carbon are making the maximum number of bonds they could with hydrogen atoms
What is a polyunsaturated fatty acid
This is a fatty acid chain that has multiple double bonds within the chain which means there are multiple carbon atoms which are fully saturated and could make more bonds with hydrogen
Why are monounsaturated and polyunsaturated fatty acids liquid at room temp
They are both liquid at room temp as the double bonds in the fatty acid chain causes a kink in the chain which means they are unable to stack properly and so are liquid at room temp
How does the body store fatty acids and how does it do it
The body is unable to store fatty acids as they are due to the chain been too long so they carboxyl group is removed and the hydrocarbon chain is bonded with a glycerol, this glycerol can bond with 3 fatty acid chains which then forms a triglyceride and is stored as fat in the body
What is the polymer of amino acids called
Polypeptide chain
How are amino acids bonded
Peptide bonds
What is an amino acid made up of
Central carbon atom which is bonded to a hydrogen atom, a carboxylic group, an amino group and a side chain which is unique to each amino acid
What are non-essential amino acids
These are amino acids we can get from food and make ourself
What are conditionally essential amino acids
Healthy bodies are able to make them
What are essential amino acids
These are amino acids that we cannot make ourself and rely on getting them from food
How do we get essential amino acids from dietary proteins
Through proteolysis
