Biomolecules Overview

Study Notes

Carbohydrates: Provide energy and structure to cells
- Monosaccharides (e.g., glucose, fructose)
- Disaccharides (e.g., sucrose, lactose)
- Polysaccharides (e.g., starch, cellulose, glycogen)
Lipids: Energy storage, structural components, and signaling molecules
- Fatty acids and glycerol (triglycerides)
- Phospholipids (cell membrane components)
- Cholesterol and steroids
Proteins: Perform various cellular functions (enzymes, transport, structure)
- Amino acids (20 standard)
- Primary, secondary, tertiary, and quaternary structure
Nucleic Acids: Store and transmit genetic information
- DNA (double helix) and RNA (single strand)

Glycolysis: Breakdown of glucose to pyruvate
- Produces ATP and NADH
- Occurs in cytosol
Citric Acid Cycle (Krebs Cycle): Breakdown of acetyl-CoA to CO2 and ATP
- Produces ATP, NADH, and FADH2
- Occurs in mitochondria
Fatty Acid Oxidation: Breakdown of fatty acids to acetyl-CoA
- Produces ATP and NADH
- Occurs in mitochondria
Protein Synthesis: Building of proteins from amino acids
- Occurs in ribosomes
- Involves transcription and translation

Hormones: Chemical messengers that transmit signals
Receptors: Proteins that bind to hormones and initiate responses
Signal Transduction Pathways: Series of molecular interactions that transmit signals
Secondary Messengers: Molecules that amplify and transmit signals (e.g., cAMP, IP3)

Carbohydrates provide energy and structure to cells, with examples including monosaccharides (glucose, fructose), disaccharides (sucrose, lactose), and polysaccharides (starch, cellulose, glycogen).
Lipids function in energy storage, as structural components, and as signaling molecules, comprising fatty acids and glycerol (triglycerides), phospholipids (cell membrane components), and cholesterol and steroids.
Proteins perform various cellular functions, including enzymes, transport, and structure, and are composed of 20 standard amino acids, with primary, secondary, tertiary, and quaternary structure.
Nucleic acids, including DNA (double helix) and RNA (single strand), store and transmit genetic information.

Glycolysis is the breakdown of glucose to pyruvate, producing ATP and NADH, and occurring in the cytosol.
The Citric Acid Cycle (Krebs Cycle) breaks down acetyl-CoA to CO2 and ATP, producing ATP, NADH, and FADH2, and occurring in the mitochondria.
Fatty acid oxidation breaks down fatty acids to acetyl-CoA, producing ATP and NADH, and occurring in the mitochondria.
Protein synthesis involves building proteins from amino acids, occurring in ribosomes, and involving transcription and translation.

Enzymes are catalysts that speed up chemical reactions without being consumed, and lower the activation energy required for a reaction to occur.
Substrates are molecules that bind to an enzyme's active site, and coenzymes are small molecules that assist enzyme function.
Inhibitors are molecules that reduce enzyme activity, and can be competitive, uncompetitive, or non-competitive.

Hormones are chemical messengers that transmit signals, binding to receptors that initiate responses.
Signal transduction pathways are series of molecular interactions that transmit signals, often involving secondary messengers like cAMP or IP3.
Receptors are proteins that bind to hormones and initiate responses, and can be located on the cell surface or within the cell.