B2.2 Organelles & Compartmentalisation - SL

Compartmentalization

The organization of different functions and processes within specific areas or structures within a cell, allowing for specialization and separation of various metabolic activities.

Catabolism

The set of metabolic pathways that break down molecules into smaller units, releasing energy in the process.

Anabolism

The set of metabolic pathways that construct molecules from smaller units, requiring energy input.

Organelle

A specialized structure within a cell that performs a specific function, often membrane-bound, and contributes to the overall function of the cell.

Plasma Membrane

A selectively permeable barrier that encloses the cell, controlling the movement of substances in and out, and providing structural support and protection.

Eukaryotic Cells

Cells that contain a nucleus and other membrane-bound organelles, found in organisms such as animals, plants, fungi, and protists.

Prokaryotic Cells

Cells that lack a nucleus and membrane-bound organelles, found in organisms such as bacteria and archaea.

Lysosome

A membrane-bound compartment within a cell that contains enzymes for breaking down and recycling waste materials and cellular debris.

Enzyme

A protein that acts as a catalyst to speed up chemical reactions without being consumed in the process.

Cytoskeleton

A network of protein fibers within the cell that provides structural support, shape, and facilitates movement and transport of materials within the cell.

Microtubules

Cylindrical structures composed of tubulin proteins that form part of the cytoskeleton, providing support and shape to the cell and facilitating movement of organelles and chromosomes during cell division.

Cell Wall

A rigid layer outside the plasma membrane in certain cells, providing structural support and protection against mechanical stress.

Cytoplasm

The gel-like matrix that surrounds organelles within the cell, containing molecules necessary for cellular processes and maintaining cell shape.

Ribosome

A non-membrane-bound structure within the cell that synthesizes proteins by translating messenger RNA (mRNA).

Nucleus

A membrane-bound compartment in eukaryotic cells that houses genetic material (DNA) and is responsible for regulating gene expression and cellular activities.

Rough Endoplasmic Reticulum

A membrane-bound organelle involved in protein synthesis and processing, characterized by the presence of ribosomes on its surface.

Smooth Endoplasmic Reticulum

A membrane-bound organelle involved in lipid synthesis, detoxification, and calcium storage, lacking ribosomes on its surface.

Golgi Apparatus

A membrane-bound organelle that modifies, sorts, and packages proteins and lipids for transport to various destinations within or outside the cell.

Mitochondria

Membrane-bound organelles that generate cellular energy in the form of adenosine triphosphate (ATP) through aerobic respiration.

Chloroplast

Membrane-bound organelles found in plants and algae that conduct photosynthesis to convert solar energy into chemical energy stored in glucose.

Vacuole

A membrane-bound compartment in cells, particularly large in plant cells, that stores nutrients, waste products, and helps maintain cell turgor.

Centrioles

Cylindrical structures composed of microtubules, involved in organizing the mitotic spindle during cell division in animal cells.

Free Ribosomes

Ribosomes suspended in the cytoplasm, responsible for synthesizing proteins that function within the cytosol.

Vesicles

Small membrane-bound sacs that transport and store substances within a cell or between cells.

Flagella

Long, whip-like structures that protrude from the cell surface, enabling motility in certain cells, such as sperm cells and some bacteria.

Nucleoid

An irregularly-shaped region within prokaryotic cells where the genetic material (DNA) is located, lacking a surrounding membrane.

DNA (Deoxyribonucleic Acid)

The molecule that carries genetic information in cells, composed of two strands forming a double helix.

Transcription

The process of copying a segment of DNA into RNA, particularly messenger RNA (mRNA), as a precursor to protein synthesis.

mRNA (Messenger RNA)

A single-stranded RNA molecule that carries genetic information from DNA to the ribosome, where it guides protein synthesis.

Translation

The process of synthesizing proteins from mRNA, occurring at the ribosome, where amino acids are assembled into a polypeptide chain.

Post-Transcriptional Modification

The processing of pre-mRNA into mature mRNA, involving the removal of non-coding regions (introns) and modifications to the ends of the molecule.

Metabolism

The sum of all chemical reactions occurring within a living organism, including catabolic reactions that break down molecules to release energy and anabolic reactions that build complex molecules from simpler ones, requiring energy input.