Biological molecules Flashcards
What are the four major classes of biological macromolecules?
- Carbohydrates
- Lipids
- Proteins
- Nucleic acids
What is the general composistion of the cell (4 things)? What are their respective percentage proportions?
What are carbohydrates used for?
Carbohydrates function as:-
- Energy storage
- Fuel
- Metabolite
- Structural element
What is the general formula for carbohydrates?
(CH2O)n
What are the two types of monosaccharides?
- Ketone based - Ketose
- Aldehyde based - Aldose
Give information about glucose.
- It is an aldose.
- It has 6 carbon atoms - it is a hexose.
- It has a D-configuration - where the hydroxly group is pointed to the right.
- It can exist in a long-chain and ring structure.
What is the difference between L and D configuration?
- In L configuration the hydroxyl group on the second last carbon atom is pointing to the left side.
- In D configuration the hydroxyl group on the second last carbon atom is pointing to the right side.
What is the difference between alpha and beta glucose?
- In alpha glucose the OH group points downwards.
- In beta glucose the OH group points upwards.
Which two monomers make up sucrose?
Glucose and fructose
Which two monomers make up lactose?
Galactose and glucose.
Give information on glycogen.
- It is an aldose
- It has 6 carbon atoms.
What is glycosylation?
It is when a carbohydrate is covalently bonded to an organic molecule to form structures like glycoproteins.
What are oligosaccharides?
Oligosaccharides are carbohydrates composed of a relatively small number of monosaccharides (3-6).
Explain the primary structure of proteins.
It is when amino acids join together by peptide bonds to form a polypeptide chain.
Explain the secondary structures of proteins.
- It is the way in which the primary structure of the proteins folds.
- Hydrogen bonds form to stabilise the structure.
- Can form alpha helixs, beta turns and beta pleated sheets.
Explain the tertiary structure of proteins.
- It is the overall 3D structure of the protein.
- It is stabilised by hydrogen bonds, hydrophilic and hydrophobic interactions, disulfide bridges and ionic bonds.
Explain the quaternary structure of proteins.
- It is the organisation of macromolecules into assemblies.
- It is often stabilised by ionic bonds.
Give information on body fats.
- They act predominanty as food reserves.
- They are glycerol esters witth fatty acids.
- They can be saturated (without double bonds) or unsaturated (with double bonds).
How does steroid enter the membrane?
- the OH group interacts with the polar lipid heads.
- Its steroid scaffold interacts with the fatty acids.
