14.2
Flashcard 1
Q: What is the function of the Golgi complex? A: The Golgi complex processes, sorts, and packages proteins and lipids received from the ER.
Flashcard 2
Q: What are the compartments of the Golgi complex? A: The Golgi complex consists of the cis-Golgi network (CGN), medial cisternae, and trans-Golgi network (TGN), each with specific functions in protein processing and transport.
Flashcard 3
Q: What are lysosomes? A: Lysosomes are the principal sites of intracellular digestion.
Flashcard 4
Q: What do lysosomes contain? A: Lysosomes contain various hydrolases that are active at low pH (acid hydrolases).
Flashcard 5
Q: What is the function of lysosomes? A: Lysosomes degrade unwanted proteins and organelles through processes like autophagy.
Flashcard 6
Q: What role do endosomes play in the cell? A: Endosomes are involved in sorting and transporting materials to lysosomes.
Flashcard 7
Q: How do ER resident proteins stay in the ER lumen? A: ER resident proteins contain retention and retrieval tags, such as the KDEL sequence (Lys-Asp-Glu-Leu).
Flashcard 8
Q: What is the function of the KDEL sequence? A: The KDEL sequence acts as a retention and retrieval tag for ER resident proteins, ensuring they are returned to the ER from the Golgi complex.
Flashcard 9
Q: How does the Golgi complex maintain its identity through continuous movement of its content? A: The Golgi complex maintains its identity through retention and retrieval signals, such as the KDEL sequence, which ensures that ER resident proteins are returned to the ER.
Flashcard 10
Q: What is the role of progressive organelle acidification? A: Progressive organelle acidification is achieved by active transport (pumping) of H+ into the lumen, which is crucial for the function of various organelles.
Flashcard 11
Q: Why is acidification important for lysosomes? A: Acidification activates acid hydrolases in lysosomes, which are essential for digestion.
Flashcard 12
Q: What is the lysosomal targeting signal? A: The lysosomal targeting signal involves the addition of mannose 6-phosphate (M6P) groups to the precursors of lysosomal enzymes in the Golgi network.
Flashcard 13
Q: How are M6P-tagged hydrolases transported? A: M6P-tagged hydrolases are recognized by M6P receptors, which facilitate their transport to endosomes and eventually to lysosomes.
Flashcard 14
Q: Give an example of regulated exocytosis. A: One example is GLUT4 translocation to the plasma membrane upon insulin signaling, which increases glucose intake in fat or muscle cells.
Flashcard 15
Q: What is another example of regulated exocytosis? A: Another example is synaptic vesicle exocytosis upon neuronal depolarization, allowing neurotransmitter release.
Flashcard 16
Q: What are the different endocytic pathways? A: The different endocytic pathways include pinocytosis, macropinocytosis, receptor-mediated endocytosis, and phagocytosis.
Flashcard 17
Q: What is pinocytosis? A: Pinocytosis is the uptake of plasma membrane along with extracellular fluid (cellular drinking).
Flashcard 18
Q: What is macropinocytosis? A: Macropinocytosis is the uptake of extracellular fluid on a large scale (non-specific).
Flashcard 19
Q: What is receptor-mediated endocytosis? A: Receptor-mediated endocytosis is the import of select extracellular macromolecules via specific receptors.
Flashcard 20
Q: What is phagocytosis? A: Phagocytosis is the ingestion of large particles (cellular eating), such as the engulfment of red blood cells by macrophages.Flashcnetwork.