Biological molecules
Monosaccharides
A carbohydrate which contains just one sugar unit
A small negative charge
A covalent bond is an electron sharing bond, in oxygen's case it is not equal. The oxygen gets slightly more than its fair share so it gives it what?
Cellulose
A polysaccharide made of thousands of glucose molecules using beta glucose molecules linked with beta 1-4 glycosidic bonds. They do not coil and are in a straight line, each molecule forms a hydrogen bond with its neighbour so produces bundles of molecules lying side by side.
Polysaccharide
A substance whose molecules are made of many monosaccharides linked together in a long chain
A condensation reaction
A triglyceride is formed during what reaction?
A central carbon atom
All amino acids have what?
Protein synthesis, on the ribosomes in a cell.
Amino acids are linked up during what process? and where does this process occur?
Why starch can be stored in small places
Amylose molecules coil around to form a long spiral, this makes them compact. The coil is held together by hydrogen bonds.
A structural protein
Apart from being a fibrous protein what else is it?
No, do not taste sweet Starches and cellulose
Are polysaccharides soluble and what do they taste like? Give 2 examples.
Yes and sweet
Are sugars soluble and what do they taste like?
Raise the temperature, High specific heat capacity
As heat is added to water the energy is used to break the hydrogen bonds between water molecules, because energy is used for this there is less energy to what? Therefore it requires a lot of energy to increase the temperature a lot, so it has what?
Condensation reactions
As the peptide bond is formed, two hydrogen atoms from one amino acid and one oxygen from another amino acid join together to form water. Reactions where water is formed and released are called what?
Fibres
Bunches of fibrils are known as what?
Steroids
Cholesterol and other substances with similar structures and that are formed from it are called what?
The fluidity of the membrane
Cholesterol regulates what?
Fibrous protein, long and thin
Collagen is what type of protein? and what shape is it?
Third part of the structure of collagen
Each complete 3 strand molecule of collagen interacts with the other, running parallel to it. Bonds form between the R groups of lysines in molecules lying next to molecules side by side. These cross links are fibrils.
Surface tension
Each water molecule in a body of water is attracted to others around it, but on the surface the uppermost molecules only have other molecules below them so they are pulled downwards. These pulling forces draw them closer together than in other parts. What is this known as?
Hydrophobic
Fatty acid tails are what?
Adipose tissue
Filled with globules of triglycerides and make very good thermal insulators.
Small, and to have groups with an electrical charge outside of the molecule. (makes them able to interact with water molecules)
For a molecule to be soluble in water what must the molecule be?
Monosaccharides
Glucose, fructose and galactose are examples of what?
Unsaturated fats
Has one or more fatty acids in which at least one carbon atom is using two of its bonds to link to a neighboring carbon atom, so it only has one bond spare to link to hydrogen. This double carbon-carbon bond forms a 'kink' in the chain.
By the peptide bond being broken
How are polypeptides broken up? An example is when protein molecules are digested in the stomach by protease enzymes.
By hydrogen bonds
How are the shapes of secondary structures held together?
It cools them by allowing water to be evaporated from the surface of the mesophyll cells inside them.
How does latent heat of evaporation benefit plants in hot climate?
By hydrogen bonds, disulfide bonds, ionic bonds and hydrophobic interactions
How is a tertiary structure held together?
20
How many amino acids are there approximately?
6 and hexose
How many carbons does glucose contain and so it is called what?
Cohesion
In a tall column of water the forces holding the molecules to each other help prevent the column breaking. What forces is this?
Animals produce mostly fats and plants oils
In general animals produce mostly what and plants produce mostly what? There are exceptions to this rule.
A globular protein
In haemoglobin the chain is curled up into a ball which forms what?
Hydrolysis reaction
In what reaction does a combination with a water molecule break apart the peptide bond between two amino acids and separate them?
Alpha helix
In what secondary structure does the hydrogen bond form between the oxygen of the -CO group of one amino acid and the hydrogen of the -NH2 group of the amino acid four places ahead of it in the chain?
No, storage
Is amylose soluble in water and what is it's function?
No, structural
Is cellulose soluble in water and what is it's function?
No, storage
Is glycogen soluble in water and what is it's function?
Between each cellulose molecule
Is the hydrogen bonding within or between molecules in a cellulose molecule?
Within
Is the hydrogen bonding within or between molecules in a glycogen molecule?
Within
Is the hydrogen bonding within or between molecules in an amylose molecule?
First part of the structure of collagen
It consists of 3 polypeptide chains each in the shape of a helix.
Structure of a water molecule
It has two hydrogen atoms covalently bonded to one oxygen atom. The bonds are very strong and are difficult to split the hydrogen and oxygen apart.
Why plants use amylose stores
It is just one helix and can bend.
How urea is removed from the body
It is the main nitrogenous excretory product of mammals, is removed from the body dissolved in water in the form of urine.
Disaccharides
Like monosaccharides they are soluble in water and taste sweet
How plants store the carbohydrate they make during photosynthesis
Linking together thousands of alpha glucose molecules with 1-4 glycosidic bonds produces Amylose found in starch, it is insoluble and metabolically inactive so it doesn't interfere with chemical reactions inside the cell nor does it affect water potential.
Amylose, starch
Linking together thousands of alpha glucose molecules with 1-4 glycosidic bonds produces what? and where is it found?
Why animals use glucose stores
Linking together thousands of alpha glucose molecules with 1-4 glycosidic bonds produces what? and where is it found?
A polypeptide
Lots of amino acids joined together form what?
Metabolic reactions
Molecules undergo chemical reactions that make things happen in and around your cells.
Hormones (testosterone and oestrogen)
Most steroids in the body are what?
Phospholipid
Much like a triglyceride but one of the fatty acids is replaced by a phosphate group
Why triglycerides are insoluble in water
None of their atoms carry an electrical charge and so they are not attracted to water and are said to be hydrophobic.
Covelent bonds
Peptide bonds also contain what type of bonds?
Carbon and nitrogen
Peptide bonds are between what molecules?
Hydrophilic (attracted to water)
Phosphate heads are what?
Bilayer
Phospholipids arrange themselves in what sheet?
Estimations of a reducing sugar concentration procedure
Produce a standard solution curve, with different concentrations of glucose (0.2,0.4,0.6,0.8) Use a specific measurement of the glucose and add a specific amount of Benedict solution. Boil water over a bunsen burner Leave the test tubes in the water until there is a colour change (brick red) Filter of the precipitate from the solution and put the filtered liquid into cuvettes and place in the colourimeter Use the colourimeter to test absorbance, using a blue filter.
Long chains of amino acids
Proteins are made of what?
Hydrophobic
R groups which contain only carbon and hydrogen atoms are what?
Why animals can walk on the surface of water
Surface tension forms a strong layer on the surface of the water, strong enough for animals to be able to walk on the surface.
Second part of the structure of collagen
The 3 polypeptide chains wind around each other to form a 'rope', almost every third amino acid in each polypeptide is glycine, the smallest, so it allows the 3 strands to lie close together and form a tight coil. Held together by hydrogen bonds
300N per mm2 of cross sectional area
The Achilles tendon can withhold a pulling force of what?
Haemoglobin and a haem group
The beta polypeptide chains wind itself around a little group of atoms with an iron ion at the center. What molecule is this and what is the iron ion group called?
A hydrolysis reaction
The breaking of an ester bond is what type of reaction?
How a triglyceride is formed
The carboxyl groups of fatty acids can react with the -OH (hydroxyl) groups of glycerol forming ester bonds. These involve covalent bonds so are very strong.
Boiling point
The energy needed to break hydrogen bonds affects what?
Saturated fats
The fatty acid contains as much hydrogen as they can, each carbon atom in the fatty acid tail is linked to its neighboring carbon atoms by single bonds while the other two bonds are linked to hydrogen atoms
A small positive charge
The hydrogen molecules in an oxygen have what?
The formation of a glycosidic bond by a condensation reaction
The hydroxide ion of an alpha glucose and the hydrogen ion of a beta glucose react together during a condensation to produce water and join the two molecules together. An alpha 1-4 glycosidic bond is formed. The oxygen is left combining the two glucose molecules together forming maltose.
2, 8
The iron ion in each of the 4 haem groups in a haemoglobin molecule is able to bond with how many oxygen atoms and so one molecule of haemoglobin can carry how many oxygen atoms?
Dissolving
The molecules and ions spread around in between water molecules.
Tertiary structure
The overall shape formed by a protein molecule
Quaternary structure
The overall shape of a protein molecule that is made up of two or more intertwined polypeptides
Why the phosphate heads are hydrophilic
The phosphate group has a negative electrical charge on the hydrogen atoms in a water molecule. So when it is in water the two ends of a phospholipid molecule do different things.
Secondary structure
The regular arrangement of a protein.
Primary structure
The sequence of amino acids linked together in a polypeptide or protein
Their structures
The solubility of globular and fibrous proteins depends on what?
blood plasma blood clot
The soluble globular protein fibrinogen is found in the..........., is converted into the insoluble fibrous protein fibrin when a blood vessel is damaged. The fibrin fibres form a network across the wound in which platelets can be trapped to form a........
Triglycerides
Their molecules are made up of 3 fatty acids attached to a glycerol molecule.
Hydrophobic bond
There is a slight attraction between the R groups, it is quite a weak bond.
Lipids
They are made up of carbon, hydrogen and oxygen but have a much higher proportion of hydrogen than carbohydrates. They are also insoluble in water
Fibrous protein
They are not soluble in water and not usually metabolically active, most of them such as collagen have a structural role.
Solvent
They have tiny charges on the molecules which attract other molecules or ions that have a charge, this makes it an excellent what?
Ionic bond
This bond forms between a R group with a full negative charge and one with a full positive charge. This bond is much stronger than a hydrogen bond, it can be broken by changes in pH.
Disulfide bonds
This bond forms between the R groups of the amino acid cysteine. they are very strong covalent bonds but can be broken by reducing agents. They are often important in holding together the different polypeptide chains in the quaternary structure.
Hydrogen bond
This bond is not very strong and can be broken by high temperatures and a change in pH.
Fibrous protein
This protein has a variable primary structure, with a limited range of different amino acids that can be joined together to form chains of varying lengths.
Globular protein
This protein must have a very precise shape because this determines the function and so have a very precise primary structure.
twice as much (so they make compact and efficient stores)
Triglycerides can release how much more energy than one gram of carbohydrate when it is respired?
Disaccharide
Two monosaccharide molecules linked together to form a sugar
Viscous
Water is a fairly what fluid?
Why water is dense (1.0 cm-3)
Water molecules are pulled closely together by hydrogen bonds.
Cohesion
Water molecules often stick together
Alpha helix and beta fold
What are 2 types of secondary structures?
Sugar molecules
What are carbohydrates made of?
Fat soluble vitamins (vitamin D and vitamin A)
What are stored triglycerides very good at storing?
Carboxyl group (-COOH), hydrogen atom, the amino group (-NH2) and the R group.
What are the 4 bonds that a central carbon atom bonds with in an amino acid?
Fibrils, fibres
What are the bundles of molecules in cellulose molecules called? And what are a larger bundle of these called?
Primary structure (amino acid sequence)
What are the places in which different kinds of bonds can formed determined by?
By hydrogen bonds, disulfide bonds, ionic bonds and hydrophobic interactions (the same as the tertiary structure)
What bonds hold together the quaternary structure?
Glycogen
What can be easily broken down to form glucose by the enzyme glycogen phosphorylase, which is activated by insulin when blood glucose levels are low?
Hydrogen bonds
What causes water to be liquid at room temperature?
The function
What does the shape of a molecule determine about it?
That they are attracted to each other
What does the tiny charges in water molecules mean?
The molecules have enough energy to break apart from each other and so it causes the liquid to turn into gas.
What happens when water reached 100C?
Maltose (when two alpha glucose molecules reacted together)
What is an example of a disaccharide?
An enzyme
What is an example of a globular protein?
Latent heat of evapouration
What is our major cooling mechanism?
CH2-SH
What is the R group of cysteine?
Hydrogen bond
What is the bond called between slightly positively charged hydrogen and slightly negatively charged oxygen in a water molecule?
Beta glucose has the OH and H the opposite way round
What is the difference between an alpha glucose and a beta glucose molecule?
CnH2nOn
What is the general formula for a carbohydrate?
Straight chain, forms sheets/layers
What is the overall shape of a cellulose molecule?
Helix with branches
What is the overall shape of a glycogen molecule?
Curved helix/coil
What is the overall shape of an amylose molecule?
A fatty acid
What is this a picture of?
Alpha glucose molecule
What is this a structure of?
Hydrogen bonding between water molcules
What is this?
Peptide bond
What it the bond called between amino acids?
Change their average density by filling or emptying parts of their body with air. ( This helps them float or sink)
What methods do aquatic organisms have to swim easily?
A condensation reaction
What reaction causes a peptide bond to be formed?
Condensation reaction and a glycosidic bond
What reaction causes two monosaccharides to link together to form a disaccharide and what is the bond called?
Rigid lattice form
What structure is water in when frozen (ice)?
alpha glucose or beta glucose
What two forms can glucose exist in?
Transporter molecules found in cell membranes
What type of globular proteins are insoluble?
Latent heat
What type of heat is needed for sweat to evaporate from the body?
Solution
When an ionic compound e.g. sodium ions and chloride ions become separated from each other it makes them easy to react with other ions or molecules, this shows most metabolic reactions will only take place in what?
A hydrolysis reaction
When carbohydrates are digested, glycosidic bonds are broken down by carbohydrase enzymes. The enzyme that breaks apart maltose is maltase. What type of reaction is this?
The heat energy from the body, cold.
When liquid sweat is on our skin the water in the sweat absorbs what as it evaporates, which often makes people feel what?
In the liver and muscles
Where are glycogen stores found?
Skin, tendons cartilage, bones teeth and the walls of blood vessels
Where is collagen found?
Covalent because it shares electrons
Which is stronger a covalent bond or a hydrogen bond and why?
Alpha glucose, alpha 1-4
Which monosaccharide is amylose formed from? And what type of glycosidic bond?
Beta glucose, beta 1-4
Which monosaccharide is cellulose formed from? And what type of glycosidic bond?
Alpha glucose, alpha 1-4 and alpha 1-6
Which monosaccharide is glycogen formed from? And what type of glycosidic bond?
To help them cut through water more easily
Why are aquatic organisms often streamlined?
Because they contain a carboxyl group
Why are fatty acids acids?
They are too large
Why are fibrous proteins generally not soluble in water?
The chain folds so the R groups carrying charges are outside whilst the other are inside.
Why are globular proteins generally soluble in water?
Because if not there would be a weak spot running across the collagen fibrils.
Why are the ends of the parallel collagen molecules staggered?
Their density is close to that of water
Why can most living organisms swim easily?
It is an oxygen transporter
Why is a haem group essential for the haemoglobin molecule?
Because not many animals have the enzymes to break up the beta 1-4 glycosidic bond
Why is cellulose difficult to digest?
The temperature of water does not change quickly.
Why is it good for humans to be made up of mostly water?
Because water is nearly always present around a protein and in between its chains.
Why will hydrophobic R groups often be found together?
Why it takes a larger amount of effort to swim in water
You have to push aside molecules which are attracted to one another and therefore they are reluctant to move apart.
