BIO 101 EXAM 2

Diffusion

Movement of molecules from a high concentration to a low concentration; 'down the concentration gradient'.

Osmosis

Facilitated diffusion of water from high water concentration to low water concentration via aquaporin.

Facilitated Diffusion

Diffusion of large and charged molecules across the cell membrane through a specific transport protein.

Active Transport

Pumping molecules against their concentration gradient (low to high concentration) using energy (ATP).

Passive Transport

Diffusion of molecules down the concentration gradient (high to low concentration) with no energy required.

Simple Diffusion

Diffusion of small and uncharged molecules across the cell membrane without the help of a protein.

Reverse Osmosis

Filtering of water through a semipermeable membrane; proposed solution to dwindling water resources.

Phospholipid

A molecule with a polar head (hydrophilic) and two non-polar hydrophobic fatty acid tails.

Gradient

Concentration difference between two solutions.

Enzymes

Biological catalysts that speed up chemical reactions by lowering activation energy; most are proteins.

Metabolism

The sum of all chemical reactions inside a cell, regulated by enzymes.

Electron Transport Chain (ETC)

Series of proteins that transports electrons and produces ATP; found in the inner mitochondrial membrane.

Photosynthesis

Chemical process converting CO2 and H2O into glucose using light energy.

Calvin Cycle

Process occurring in the stroma of chloroplasts where CO2 and H2O are fixed into glucose using ATP and NADPH.

ATP

A vital molecule for energy transfer in cells, functioning as the currency for biological energy.

NAD

A coenzyme that exists in two forms (NAD+ and NADH) and is involved in electron transport and energy production.

Fermentation

Energy extraction without oxygen, occurring in anaerobic conditions; includes lactic acid and alcohol fermentation.

Mutualistic relationship

An interaction between two organisms where both benefit from each other.