Cellular Structures and Organelles

Flashcards covering key vocabulary related to cell structures and organelles.

Organelles

Structures within the cytoplasm of eukaryotic cells, mostly delimited by membranes, facilitating compartmentalization of cellular processes.

Cytoskeleton

A supportive framework within the cytoplasm, crucial for maintaining cell shape and transporting materials.

Vacuoles

Reservoirs within cells, surrounded by a membrane called the tonoplast, used for storage.

Tonoplast

The membrane surrounding a vacuole in plant cells.

Membranous Organelles

Organelles bounded by membranes, including the endoplasmic reticulum, Golgi apparatus, and lysosomes.

Non-Membranous Organelles

Organelles not bounded by membranes, such as ribosomes.

Endoplasmic Reticulum (ER)

A network of interconnected membranes within eukaryotic cells, involved in protein and lipid synthesis.

Lumen of ER

The internal space enclosed by the endoplasmic reticulum membrane.

Rough Endoplasmic Reticulum (RER)

Endoplasmic reticulum with ribosomes attached to its surface, involved in protein synthesis and modification.

Smooth Endoplasmic Reticulum (SER)

Endoplasmic reticulum without ribosomes, involved in lipid synthesis, detoxification, and carbohydrate metabolism.

Ribosomes (bound)

Ribosomes attached to the rough endoplasmic reticulum, primarily involved in synthesizing proteins for export or internal use.

Chaperone Proteins

Enzymes that catalyze the correct folding of proteins within the endoplasmic reticulum.

Proteasomes

Structures in the cytosol responsible for degrading defective proteins.

Transport Vesicles

Membrane-bound sacs that bud off from the endoplasmic reticulum, transporting proteins to other organelles.

Signal Sequence

A sequence of amino acids on a polypeptide chain that directs ribosomes to the endoplasmic reticulum.

SRP (Signal Recognition Particle)

A complex of proteins and RNA that binds to the signal sequence and directs the ribosome to the ER membrane.

SRP Receptor

A membrane protein on the ER that binds to the SRP-ribosome complex, facilitating the attachment of the ribosome to the ER.

Glycosylation

The addition of oligosaccharides to proteins within the endoplasmic reticulum.

Glycoproteins

Proteins that have been modified by the addition of oligosaccharides.

Golgi Apparatus

An organelle involved in processing and packaging macromolecules synthesized in the ER.

Cisternae

Flattened, membrane-bound sacs that make up the Golgi apparatus.

Dictyosomes

Stacks of cisternae within the Golgi apparatus.

Cis Face (of Golgi)

The receiving side of the Golgi apparatus, associated with the ER.

Trans Face (of Golgi)

The shipping side of the Golgi apparatus, oriented towards the plasma membrane.

Lysosomes

Organelles containing digestive enzymes, involved in breaking down macromolecules and cellular debris.

Hydrolases

Digestive enzymes found in lysosomes, capable of hydrolyzing various macromolecules.

Primary Lysosomes

Newly formed lysosomes containing inactive enzymes.

Secondary Lysosomes

Lysosomes that have fused with other vesicles or organelles, containing active enzymes and substances to be digested.

Autophagy

A process by which lysosomes degrade damaged or unnecessary cellular components.

Autolysis

The self-destruction of a cell through the release of lysosomal enzymes.

Peroxisomes

Organelles containing enzymes that catalyze oxidation reactions, producing hydrogen peroxide.

Oxidases

Enzymes within peroxisomes that oxidize substances, producing hydrogen peroxide.

Catalase

An enzyme in peroxisomes that breaks down hydrogen peroxide into water and oxygen.

Glioxisomas

Peroxisomes found in plant seeds, containing enzymes that convert fats into sugars.

Vacuoles

Large, membrane-bound sacs in plant and fungal cells, used for storage and maintaining cell turgor.

Tonoplast

The membrane surrounding the vacuole in plant cells.

Turgor Pressure

The pressure exerted by the vacuole against the cell wall, maintaining cell rigidity.

Rough ER function

Synthesis and assembly of proteins.

Smooth ER function

Synthesis of carbohydrates, steroid hormones, and lipids.

Detoxification

The process of converting toxic substances into non-toxic forms, often performed by the smooth ER and peroxisomes.

Vesicle fusion

The merging of a transport vesicle with the membrane of another organelle, delivering its contents.

Cisternal maturation

The process by which Golgi cisternae mature and move from the cis to the trans face, carrying cargo with them.

Exocytosis

The process by which cells export substances by fusing vesicles with the plasma membrane.

Endocytosis

The process by which cells internalize substances by engulfing them in vesicles formed from the plasma membrane.

Macromolecules

Large molecules such as proteins, carbohydrates, lipids, and nucleic acids.

Metabolites

Small molecules that are intermediate products of metabolism.

Glycolipids

Lipids with carbohydrates attached, found on the cell membrane.

Pectins

Structural polysaccharides found in plant cell walls.

Oligosaccharides

Short chains of sugars.

N-linked oligosaccharides

Oligosaccharides attached to a protein via an asparagine residue.

Phosphorylation

The addition of a phosphate group to a molecule.

Enzyme localization

The specific location of enzymes within cellular organelles.

Phagocytosis

The process by which cells engulf large particles or other cells.

Protozoa

Single-celled eukaryotic organisms.

Contractile vacuoles

Vacuoles that eliminate excess water from the cell.

Autophagic vacuoles

Vacuoles containing cellular components to be degraded.

Residual bodies

Lysosomes filled with undigested material.

Membrane asymmetry

The difference in lipid composition between the two leaflets of a cell membrane.

Ethanol detoxification

The detoxification of alcohol, primarily occurring in liver cells.

Oleaginous seeds

Seeds rich in oils or fats.

Plastids

Organelles found in plant cells, including chloroplasts.

Polypeptides

Chains of amino acids that make up proteins.

Luz del RE

Space located inside the membranes of the endoplasmic reticulum where the proteins are assembled

Carabinas moleculares

Enzymes which catalyze the necessary folding of the proteins

Proteosomas

Structure inside the citosol where defective proteins are destroyed

Particula de reconocimiento de señal

Name given to the component needed in order to begin the process of realising the synthesis of a protein

Receptora de SRP

Receives the recognition of the signal protein-ribosome structure in the rough endoplasmic reticulum

Evaginaciones o gemaciones

How lysosomes are formed by cisternas in the Golgi apparatus

Peroxisomas

Organelos which contain enzymes with the type oxidases

Glioxisomas

Name given to peroxisomas found in plants.

The principal function of organelo in this lesson

Detoxification

Vacuola

Organelo which does not have structures inside the internal part of the cell

Lisosomas Primarias

Newly formed lysosomes which do not contain any substance to be digested by the cell.

Nucleótidos

Created from the lysosomes in their digestive process to influence the development and growth of the cell

Vacuolas contráctiles

Vacuoles that eliminate the excess water of the cell.

Vacuolas alimenticias

Type of vacuole that can usually be found in protozoarios

Proceso de Glicosilación

Process of formation of protein inside of the rough endoplasmic reticulum.

Aparato de Golgi

Organelo that acts as a passage station for the processing and package of macromolecules syntethized in the RE