Endomembrane And Bulk Transport Flashcards
What is the Endomembrane System
A membrane system interconnected by direct physical contact or transfer by vesicles
The endomembrane includes
Nuclear envelope
Endoplasmic reticulum (smooth and rough)
Golgi complex
Vesicles
Lysosomes
Vacuoles
Plasma membrane
Where does synthesis occur
Endoplasmic reticulum
Where are proteins labelled and packaged
Golgi complex
What delivers/transports proteins
Vesicles
Why can vesicles fuse with membrane of cell/organelles
Both have phospholipid bilayer
What are the functions of the smooth Endoplasmic reticulum
MLDS
Metabolism of carbohydrates
Lipid synthesis
Detoxification of drugs/poisons
Storage calcium ions
What is the functions of the rough Endoplasmic reticulum
Protein synthesis
Describe the path of proteins in the rough endoplasmic reticulum
Secreted and membrane bound proteins enter the lumen (interior) of rER
Processed by rER and the rest of the endomembrane system for release from the cell or retention on the cell membrane
What are the functions of the Golgi complex
Glycosylation - addition or modification of carbohydrates to proteins
Sorting Proteins - adds molecular markers to direct proteins to correct vesicle
Directing vesicle traffic - adds markers to vesicles leaving trans face to direct them to correct targets
What is the Golgi body
Series of membrane sacs and associated vesicles
What is meant by the Golgi body having polarity
Vesicles from endoplasmic reticulum arrive at the cis face
Processed vesicles leave at the trans face
How does the Golgi body sort proteins
Adds molecular marker to direct proteins to corresponding vesicle
How does Golgi complex direct vesicle traffic
Adds molecular tags to vesicles leaving the trans face to direct them to correct targets
What is a vesicle
A membrane bound, cytoplasm/fluid filled organelle
What are 3 types of vesicles
Transport vesicles
Secretory vesicles
Vacuoles
What is the function of secretory vesicles
To release contents outside the cell
What is the difference between vesicles and vacuoles
Vacuoles are larger than vesicles
What is the name of artificial vesicles, and what are the used for
Liposomes
For drug and vaccine delivery
What is exocytosis
The transport of material out of the cell, or delivery to the surface of the cell
What is constitutive exocytosis
Releases extracellular matrix proteins
What is regulated exocytosis
The controlled release of a substance
What is endocytosis
The intake of material at the plasma membrane
What is phagocytosis
The plasma membrane “reaching out”
Cell eating (solid materials)
Forms vacuole
What is pinocytosis
Cell “drinking”
Uptake of extracellular fluid containing various solutes
Forms a vesicle
Non selective
What is receptor mediated endocytosis
Specialised form of pinocytosis
Allows uptake bulk quantities of specific substances
Receptor proteins used to selectively capture required solute
What are lysosomes
Membrane bound organelles made by rER and Golgi body containing Hydrolytic enzymes
Interior is acidic (required for enzyme activity)
What is the function of lysosomes
They degrade proteins, lipids, carbohydrates, and nucleic acid
Release broken down products into cell
Lysosomes digest unwanted cellular materials. What is this process called
Autophagy
What are vacuoles
Large vesicles derived from rER and Golgi
What is glycosylation
Addition/modification of carbohydrates to proteins
