|GENBIO.| CELL CYCLE & RESPIRATION

Cellular respiration

The process by which cells use energy stored in organic molecules to make ATP and power work.

Glycolysis

The first stage of cellular respiration, occurring in the cytosol, where glucose is broken down into two molecules of pyruvate.

Citric Acid Cycle

The second stage of cellular respiration occurring in the mitochondrial matrix that completes the breakdown of pyruvate to CO2.

Electron Transport Chain (ETC)

The final stage of cellular respiration occurring on the inner membrane, where electrons are passed to oxygen, forming H2O.

Pyruvate oxidation

The process where pyruvate enters the mitochondria and is converted to acetyl CoA, linking glycolysis to the citric acid cycle.

Proton Motive Force

The gradient created by H ions being pumped into the inner membrane space during chemiosmosis, driving ATP production.

Interphase

The longest phase of the cell cycle during which a cell grows and duplicates its DNA before dividing.

Mitosis

The phase of the cell cycle where the cell divides, resulting in two identical diploid daughter cells.

Cytokinesis

The process where the cytoplasm of a parent cell divides, forming two daughter cells.

Density-dependent inhibition

A regulatory mechanism in which cell division stops when cells reach a certain density or crowding.

Cancer

A disease characterized by uncontrolled growth and division of abnormal cells.

Benign tumor

A mass of cells that is not cancerous and does not spread to other parts of the body.

Malignant tumor

A cancerous mass of cells that can invade surrounding tissues and spread to other parts of the body.

Cell cycle control system

The system that regulates the progression of the cell cycle through checkpoints and signaling.

Meiosis

A type of cell division that produces gametes (sex cells) with half the number of chromosomes.

Energy efficiency in cellular respiration

Only 34% of the energy stored in glucose is converted into ATP; the remainder is lost as heat.

NADH

An electron carrier that relays electrons to the electron transport chain during cellular respiration.

FADH2

An electron carrier that also relays electrons to the electron transport chain, produced in the citric acid cycle.

G1 phase

The first stage of interphase where a cell grows and evaluates conditions to begin division.

G2 phase

The second stage of interphase where the cell ensures DNA is copied correctly before mitosis.

Metastasis

The spread of cancer cells from the original site to other parts of the body.