Enzymes

Enzyme

An organic catalyst that speeds up biochemical reactions, primarily composed of proteins.

Substrate

The substance needed for an enzyme reaction that binds at the active site.

Active Site

The specific region on an enzyme where substrates bind and form an enzyme-substrate complex.

Lactase

An enzyme that catalyzes the hydrolysis of lactose, derived from the substrate lactose.

Trypsin

An enzyme that does not follow the standard '-ase' naming convention, produced by pancreatic cells.

Biological Catalyst

A substance that accelerates biochemical reactions without being consumed in the process.

Enzyme Inhibitor

A substance that slows down or stops enzyme activity; an example is lead or mercury.

Cofactor

A non-protein substance that assists an enzyme in its activity, such as vitamin B or magnesium ion.

Intracellular Enzymes

Enzymes synthesized within a cell for its own use, such as hexokinase in glycolysis.

Extracellular Enzymes

Enzymes secreted outside the cell, like trypsin, which aids in digestion.

Lock and Key Hypothesis

A model explaining how substrates fit into an enzyme's active site like a key fits into a lock.

Activation Energy

The energy required to break the bonds in a substrate so that a reaction can occur.

Optimal Temperature

The temperature at which enzyme activity is maximized, typically around 37°C for human enzymes.

Denaturation

The process by which enzymes lose their three-dimensional structure and functionality due to extreme conditions.

Optimal pH

The pH level at which an enzyme is most active, often between pH 6 and 8 for many enzymes.

Saturation Point

The level of substrate concentration at which all active sites of enzymes are occupied, limiting further reaction rate.