Biological Molecules Flashcards
what are the four macromolecules? 
carbohydrates, lipids, proteins, and nucleic acids
what are macromolecules
The key components in which cells are made from
What are monomers?
Smaller units from which larger molecules are made
what are polymers?
Large molecule is made from many repeating monomer units
What is cellulose made from?
Celulose is a polymer made from lots of beta glucose monomers join together in chains
If a monomer is a monosaccharide, what is the name of the polymer?
A polysaccharide, e.g. starch, glycogen, Celulose
If a monomer is an amino acid, what is the polymer?
A polypeptide or a protein
If a monomer is a nucleotide, what is the polymer?
A nucleic acid, e.g. DNA and RNA
What is a condensation reaction?
A condensation reaction involves joining two molecules together and forming a chemical bond while creating a water molecule
What is a hydrolysis reaction?
A reaction that uses water break a chemical bond and split apart two molecules
what are carbohydrates?
Carbohydrates are molecules made from carbon, hydrogen, and oxygen only. (CHO).
what are carbohydrates made from?
Sugar molecules
what is the name for sugar molecules?
Saccharides
What are disaccharides?
Two sugar units
What are monosaccharides?
One sugar unit, they are the building blocks of all carbohydrates
what are polysaccharides?
Many repeating sugar units
what is the general formula for a monosaccharide?
(CH20)n
what are monosaccharides used for?
Respiration and growth
Three examples of monosaccharides
Galactose, glucose and fructose
what are the different types of glucose?
Alpha glucose and beta glucose
what makes beta glucose differ from alpha glucose?
Alpha glucose is bottom heavy meaning that there is a hydrogen on top and an OH on the bottom, however, on one side of the beta glucose, the OH is on top and hydrogen is underneath
What’s an isomer?
Molecules with the same atoms with different arrangements in space
How are disaccharide is formed?
when two monosaccharides are joined together in a condensation reaction
Give three examples of disaccharides.
maltose, sucrose, lactose
What is the disaccharide maltose made of?
Two. Glucose monosaccharides.
What is the disaccharide sucrose made from?
One glucose and one fructose monosaccharide
What is the disaccharide lactose made from?
One glucose, and one galactose monosaccharide
what is the type of chemical bond joins two carbohydrate monomers?
glycosidic bond
what would be the products of two glucose molecules join together to form a disaccharide?
Maltose and water
name the type of reaction that joins monomers together?
Condensation reaction
Give three examples of polysaccharides
Starch, glycogen, cellulose
Which saccharides are sweet and soluble, and which are not sweet and insoluble?
Monosaccharides and disaccharides are sweet, insoluble, but polysaccharides are not
How do you test for starch?
Iodine solution test
How do you test for reducing and non-reducing sugar is?
Benedicts test
What is the method for testing for starch?
first place, a small sample of test solution into the test tube. Then add a few drops of iodine solution.
If the iodine turns from a brown colour to blue black then starch is present.
give a method for the test for reducing sugars
First place, a sample of test solution into a test tube. Then add 10 drops of Benedicts solution, then place the test tube in a hot water bath.
If the solution contains reducing sugars, then it will go from being blue to green, yellow, or red
and how does the reducing sugars test work?
Reducing sugars reduce the blue copper sulphate in Benedicts into orange copper oxide precipitate.
what kind of test is the test for reducing sugars?
Semi quantitive
give a method for the test for non-reducing sugars?
take a sample that has previously tested negative for reducing sugar. Boil the test solution with dilute hydrochloric acid for a few minutes to hydrolyse glycosidic bonds. Neutralise with alkali. Repeat with Benedicts test. Green, yellow, and red colours indicate the presence of non-reducing sugar.
Name a non-reducing sugar
Sucrose
What is a qualitative test?
Attest, that can tell you whether a particular molecule is present from a sample
What is a quantitative test?
Attest that indicates how much of a molecule is present in a sample
The enzyme sucrase catalyses the breakdown of sucrose into monosaccharides, what type of reaction is this breakdown?
Hydrolysis
How do you test for proteins?
Biuret solution
What is the serial dilution?
A series of dilutions of a substance by a dilution factor
What is the formula involving serial dilutions?
dilution factor = Final volume of solution/volume from stock solution
what is starch?
starchis the storage carbohydrate in plants. It is actually a mixture of two polysaccharides.
What two polysaccharides is starch made from?
Amylose and Amylopectin
What is the name of the enzyme that breaks down starch?
Amylase
what is the structure of amylose?
It’s made of alpha glucose and all the glucose molecules, and joined together by 1,4 glycosidic bonds. This makes it a long unbranched chain. because of the angle of the bonding the Amylose becomes coiled.
what is the structure of amylopectin?
Amylopectin is made up of alpha glucose. It has mostly 1,4 glycosidic bonds but it also has numerous 1,6 glycosidic bonds, which results in branching.
What would be the function of a coiled molecule?
Being coiled, makes a molecule more compact for storage in a cell
What function would be branched have in a molecule?
Having branches means more ends for fast breakdown/enzyme action
why is the insoluble structure of starch helpful for its function?
Because it doesn’t cause the movement of water in and out of a cell by osmosis, as it has no effect on water potential.
What is glycogen?
The storage carbohydrate in animals.
What is the structure of glycogen?
it has a similar structure to amylopectin in starch however, it has shorter chains and it’s more highly branched.
What is the function of glycogen having smaller chains and highly branched structure?
it means it can be readily hydrolysed into alpha glucose to meet the greater energy demands of animals.
What is cellulose used for?
Cellulose makes up a plant cell wall.
what is the structure of cellulose?
cellulose is a polymer made from beta glucose. because in beta glucose, the OH and H switch on each side, each molecule has to rotate to be able to bond and therefore our inverted so it has very long straight chains that are unbranched. All of the trains are parallel to each other and connected with H bonds, which together a very strong.
why does the structure of Celulose help with its function?
because the cell wall in a plant cell is required to give the cell structure so all of the H bonds that make cellulose strong, make the cell wall strong.
which polysaccharides have 1,6 glycosidic bonds as well as 1,4 bonds?
glycogen and starch (amylopectin)
what are the roles of lipids?
I am plasma membranes, they contribute to flexibility and transfer of lipid soluble substances across them, there, an energy source, they waterproof things like waxy, cuticles implants, they are for insulation and protection
What are lipids?
I mixed group of hydrophobic compounds
What are lipids in soluble in?
Water, but they are soluble in inorganic substances like alcohol
What are triglycerides made up of?
And one glycerol molecule and three fatty acids
Where does the bonds take place to create a triglyceride?
at the hydroxyl’s of the glycerol and fatty acids
What kind of reaction happens when lipids are made?
Condensation
How many water molecules are produced when a triglyceride is made?
And three
What is the R group in a fatty acid?
is a hydrocarbon chain, R groups just mean that they vary
What makes a fatty acid saturated?
There are no double bonds between the adjacent carbon atoms
What makes a fatty acid unsaturated?
There is at least one double bond between adjacent carbon atoms
what is the bond in lipids called?
Ester Bond
How to phospholipids differ from triglycerides?
Instead of three fatty acids, they only have two and one is substituted by a phosphate containing group
in a phospholipid, why is the phosphate head on the opposite side of the fatty acids?
Because it is polar and fatty acids or nonpolar. The phosphate group is therefore hydrophilic and the fatty acids are hydrophobic.
How much is a phospholipid bilayer formed?
Hydrophobic tails are attracted to each other and form the inside of the bilayer away from water, the hydrophilic heads are placed on the outside of the bilayer in contact with water because they are attracted it.
