Introduction to Biochemistry Lecture Flashcards

Flashcards covering the fundamentals of biochemistry, biomolecules, cell solutions, and metabolic reactions based on the introductory lecture at Cagayan State University.

Biochemistry

The branch of science that studies the chemical substances found in living organisms and the chemical reactions or interactions that allow life to exist at the molecular level.

Carbohydrates

Biomolecules that serve as an immediate source of energy for the body.

Lipids

Biomolecules used for long-term energy storage and insulation.

Proteins

Biomolecules that build and repair tissues and function as enzymes.

Nucleic acids

Biomolecules responsible for storing genetic information.

Cell

A highly organized and complex system made of biomolecules that acts as the primary site of biochemical activities.

Bioinorganic substances

Substances found in the cell such as Water (about $70\%$) and Inorganic Salts (about $5\%$).

Bioorganic substances

Carbon-based substances in the cell including Proteins ($15\%$), Lipids ($8\%$), Carbohydrates ($8\%$), and Nucleic acids ($2\%$).

True Solution

A solution containing the smallest particles that are completely dissolved and transparent.

Colloid

A mixture with medium-sized particles that are suspended and appear slightly cloudy.

Suspension

A heterogeneous mixture with the largest particles that are undissolved and eventually settle out over time.

Diffusion

A passive process where molecules move from an area of high concentration to an area of low concentration until equilibrium is reached.

Osmosis

The passage of water molecules through a semi-permeable membrane in response to a solute concentration gradient or pressure gradient.

Dialysis

A process where small simple molecules (e.g., urea, salts) are separated from larger complex molecules (e.g., proteins) by diffusion through a semi-permeable membrane.

Depression of Freezing Point

The lowering of a liquid's freezing point in proportion to the amount of dissolved substances, which interfere with the molecules' ability to organize into ice.

Surface Tension

A property of liquid surfaces whereby they exhibit features of a stretched elastic membrane due to net inward attraction caused by hydrogen bonding.

Brownian Movement

The continuous, random, zigzag motion of colloidal particles caused by constant collisions with the molecules of the surrounding liquid or gas, preventing them from settling.

Tyndall Effect

A property of colloids where tiny particles scatter or bounce light in different directions, making the path of the light beam visible.

Enzymes

Biological catalysts that speed up chemical reactions in living organisms without being consumed or permanently changed.

Oxidation (Dehydrogenation)

A reaction where a molecule loses electrons, often through the removal of hydrogen atoms ($H$), which are then accepted by carriers like $NAD^+$ or $FAD$.

Reduction

A reaction where a molecule gains electrons or hydrogen atoms, effectively storing transferred energy.

Hydrolysis

A type of catabolism involving the chemical breakdown of a substance due to a reaction with water.

Condensation (Dehydration Synthesis)

A type of anabolism where two molecules are joined into one larger molecule by the removal of water.

Decarboxylation

The removal of a carboxyl group ($-COOH$) from a molecule, usually in the form of carbon dioxide ($CO_2$).

Phosphate Transfer

The movement of a phosphate group ($PO_4^{3-}$) from one molecule (like $ATP$) to another, catalyzed by enzymes such as Kinase.

Transamination

The transfer of an amino group ($-NH_2$) from one molecule to another, used for amino acid synthesis and protein metabolism.

Transmethylation

The transfer of a methyl group ($-CH_3$) from one molecule to another, involved in processes like DNA regulation and neurotransmitter synthesis.