Biological Molecules Flashcards
Monomer
one of many small molecules that combine to form a polymer
Polymer
large molecule made from many similar repeating units
Macromolecule
large molecule formed due to polymerisation of monomers
Examples of monomers
- monosaccharides
- amino acids
- nucleotides
Examples of polymers
- polysaccharides
- proteins
- nucleic acids
Condensation reaction
a chemical reaction where two molecules join together by the removal of a water molecule
Hydrolysis
a chemical reaction where a chemical bond is broken by the addition of a water molecule
Types of monosaccharides
- Pentose ( 5C )
- Hexose ( 6C )
Glycosidic bond
a C-O-C link between two molecules formed by a condensation reaction
What are the differences between DNA and RNA?
DNA contains the sugar deoxyribose and is double-stranded with bases adenine, thymine, cytosine, and guanine. RNA contains the sugar ribose, is single-stranded, and has uracil instead of thymine.
What is ATP and its role in the cell?
ATP (adenosine triphosphate) is the primary energy carrier in cells. It releases energy when its phosphate bonds are hydrolyzed.
Function of monosaccharides
Energy source and building blocks for other carbohydrates.
Function of disaccharides
Energy source
Function of polysaccharides
- Energy storage (starch, glycogen)
- structural support (cellulose).
Function of lipids
- Energy storage
- insulation
- protection.
Structure of phospholipid
Glycerol + 2 fatty acids + phosphate group.
Function of phospholipid bilayer
Major component of cell membranes (phospholipid bilayer).
Saturated fats
No double bonds, solid at room temperature.
Unsaturated fats
One or more double bonds, liquid at room temperature.
Function of amino acids
Building blocks of proteins.
Structure of amino acids
Central carbon, amino group, carboxyl group, R group (side chain).
Levels of Protein Structure
- primary
- secondary
- tertiary
- quatenary
Primary structure
each amino acid is linked to the next though peptide bonds to form a polypeptide chain
Tertiary structure
the polypeptide chain coils furthermore to form a globular shape held together by
Secondary structure
1 polypeptide chain coils into a 3D shape which is held in shape by hydrogen bonds
-> α-helix
-> β-pleated sheets
Quaternary structure
Adhesion
Water molecules stick to other surfaces.
Properties of Water
- Cohesion
- Adhesion
- High Specific Heat
- High Heat of Vaporization
- Solvent Properties
Cohesion
Water molecules stick together.
High Specific Heat
Stabilises temperature.
High Heat of Vaporisation
Cooling mechanism.
Solvent Properties
Dissolves many substances, important for biochemical reactions.
Role of Water in Living Organisms
- Transport
- Temperature Regulation
- Metabolic Reactions
Transport
medium for transporting substances
Temperature regulation
helps maintain stable body temperature
Metabolic reactions
Participates in hydrolysis and condensation reactions.