2.1 Molecules to metabolism

State the purpose of molecular biology. Explain what needs to be elucidated for this purpose.

Seeks to understand biological activity at a molecular level.

Needs to elucidate
1. The structure and function of chemical substances
2. Determine how their interactions are apart of living processes

(1) Explain why carbon compounds are important in understanding chemical substances.

Carbon atoms are important because:
1. Can form four covalent bonds, allowing a diversity of stable chemical compounds to exist.
2. Result: Life (based on such biochemicals) are based on carbon compounds. 4 mains:
a) Carbohydrates
b) Lipids
c) Proteins
d) Nucleic acids

(1) Describe the key features of the molecular structure of 3 key biochemicals.

1. Sugar
2. Lipids
3. Amino acids
Wait for 2.3&2.4

(1) Draw the molecular diagrams of examples of the 3 biochemicals.

1. Sugar: Glucose, Ribose
2. Lipids: Saturated fatty acid
3. Amino acid: Generalised amino acid (see doc)

(2) Define and outline the main living processes.

Metabolism: Web of all the enzyme-catalysed reactions in a cell or organism (Anabolism + Catabolism)

Anabolism: Metabolic reactions that build complex molecules from simpler molecules.

Through condensation reactions:
- Smaller monomers covalently bond together to form a larger macromolecules.
- Water is produced as a byproduct.

Catabolism: Metabolic reactions that break down complex molecules into simpler molecules.

Through hydrolysis reactions:
- The covalent bonds between larger macromolecules (polymers) are broken down into smaller monomers.
- Water is consumed to break the bonds.

(History) Define the theory of vitalism.

A non-scientific idea that
1. Living organisms contain 'life force' that gives it the properties of life.
2. Organic molecules (from/ in living organisms) cannot be synthesised without 'life force' in living organisms.

(History) Explain an example of a compound that debunks the theory of vitalism.

#2: Urea. Wohler synthesised urea, an organic molecule, from inorganic components.

From organisms:
- In liver, ammonia (a byproduct of metabolism) is converted to urea.
- Excreted from body via kidneys.

Artificial synthesis:
- Reaction between ammonia + carbon dioxide.