Cell Organelles and Degradation Pathways

Vocabulary flashcards covering organelles (Golgi apparatus, mitochondria, chloroplasts) and cellular degradation processes (phagocytosis, endocytosis, autophagy, crinophagy) based on the lecture notes.

Phagocytosis

A cellular process that engulfs extracellular pathogens (such as bacteria) to form a phagosome.

Endocytosis

A cellular process that takes in extracellular fluid and molecules via early to late endosomes.

Autophagy

A cellular process that encapsulates damaged organelles (such as a mitochondrion) into an autophagosome.

Crinophagy

A cellular mechanism responsible for the direct degradation of unreleased secretory granules.

Golgi Apparatus

A single membrane-bound organelle surrounded by a phospholipid bilayer membrane that possesses structural polarity and modifies, packages, and routes proteins and lipids.

Cis Face

The receiving face of the Golgi apparatus that takes in incoming transport vesicles.

Trans Face

The shipping face of the Golgi apparatus from which newly forming vesicles and secretory vesicles exit.

Glycosylation

The major process occurring in the Golgi apparatus where proteins and lipids are modified by adding carbohydrate chains to form glycoproteins and glycolipids.

Lysosome Formation

The process in which the Golgi apparatus packages hydrolytic digestive enzymes into membrane-bound vesicles to generate lysosomes.

Semiautonomous Nature of Chloroplasts

The characteristic of chloroplasts containing $70S$ ribosomes and naked circular DNA, allowing self-replication via binary fission and independent protein synthesis.

Chloroplast Outer Membrane

The permeable membrane enclosing the chloroplast that regulates the transport of small molecules.

Chloroplast Inner Membrane

The selectively permeable membrane regulating the passage of ions, proteins, and metabolites into the stroma.

Stroma

The fluid-filled matrix of a chloroplast containing Rubisco and enzymes for the Calvin cycle (Light-Independent Stage).

Thylakoids

Membrane-bound disc-like sacs containing chlorophyll that host the Light-Dependent Stage of photosynthesis.

Granum

A stack of thylakoids (plural: grana) that maximizes surface area for efficient light absorption.

Lamella

Tubular membranes (intergranal lamella) connecting adjacent grana, ensuring spatial separation and stability within the chloroplast.

Mitochondrial Outer Membrane

The outer boundary enclosing the mitochondrion containing porin proteins that allow free passage of small molecules and ions.

Mitochondrial Inner Membrane

A selectively permeable membrane housing Electron Transport Chain (ETC) complexes and ATP synthase for oxidative phosphorylation.

Mitochondrial Intermembrane Space

The region between the outer and inner mitochondrial membranes where protons ($H^+$) accumulate to create an electrochemical gradient.

Cristae

Infoldings of the inner mitochondrial membrane that maximize the surface area for ATP synthesis and electron transport chains.

Mitochondrial Matrix

The fluid-filled space containing enzymes for the Krebs cycle, circular DNA, $70S$ ribosomes, and metabolic substrates.

ATP Synthase Particles

Enzyme complexes located on the cristae that use proton motive force to synthesize ATP from ADP and inorganic phosphate.

Mitochondrial DNA

Small, naked, circular DNA loop encoding specific mitochondrial proteins and RNAs that enables self-replication.

Mitochondrial Ribosomes

Prokaryotic-like $70S$ ribosomes inside the matrix that synthesize proteins coded by mitochondrial DNA.

Mitochondrial Granules

Dense matrix structures involved in ionic regulation and storage of divalent cations such as calcium ($Ca^{2+}$).

Cellular Degradation Pathways Diagram

Diagram showing cellular degradation pathways including phagocytosis, endocytosis, autophagy, and crinophagy leading to lysosomal degradation.

Golgi Apparatus Structure Diagram

Diagram showing the structure and polarity of the Golgi apparatus, including cisternae, incoming transport vesicles, cis face, lumen, trans face, and secretory vesicles.

Chloroplast Double Membrane & Thylakoid Diagram

3D diagram showing the inner and outer membranes, grana stacks, and thylakoid system of a chloroplast.

Mitochondrion Structure Diagram

Cross-section diagram illustrating the components of a mitochondrion, including cristae, matrix, ribosomes, granules, ATP synthase particles, and membranes.

Chloroplast Anatomy Diagram

Diagram highlighting the structural organization of a chloroplast including stroma, thylakoids, granum, lamella, inner membrane, and outer membrane.