Lecture 4 Flashcards
what is an Endomembrane system
a membrane system interconnected by direct physical contact or transfer by vesicles
what does the endomembrane system include
nuclear envelope, lysosomes, ER, vacuoles, golgi apparatus, plasma membrane and vesicles
What are the two types of Endoplasmic Reticulum
Smooth and Rough
What are the functions of sER
Metabolism of Carbohydrates
Lipid Synthesis/formation
Detox of Drugs/poison
Storage of calcium ions
how does sER meet the demand of its processes in cells
it can increase/decrease to meet demand
What is rER and what its functions
ER covered in ribosomes,
ribosomes for protein synthesis/production
what happens to rER proteins
secreted and membrane-bound proteins enter lumen(inferior) of rER
Processed for release from cell or retention on cell membrane
What is the Golgi Complex
series of membrane sacs and associated vesicles
What are the functions of the Golgi Complex
Receives,modifies, sorts and ships proteins arriving from rER
What are the cis and trans face of the Golgi complex
has polarity: cis and trans face
Vesicles from ER arrive at Cis face
Processed vesicles leave at trans face
what is Glycosytation
the addition or modification of carbohydrate sugar to proteins, this is important for secreted or cell surface proteins
can also produces polysaccharide-can be secreted from cell
how does the Golgi complex sort proteins
it adds markers to proteins to sort in correct vesicles leaving cell
how does the Golgi complex direct vesicle trafficking
it tags vesicles with short proteins to direct to the lysosome and secretory pathways
what is exocytosis
transport material/glycoproteins out of cell or to the cell surface
What is constitutive exocytosis
relatively unregulated- releases ECM proteins
what is regulated exocytosis
releases hormones and neurotransmitters
What is endocytosis
process that takes in molecules/particles at plasma membrane
what is Phagocytosis
when a cell is “eating” uptake of food particles
forms phagocytic vacuole (large vesicle), digested by lysosomes
What is Pinocytosis
when a cell is “drinking”- extracellular fluid, containing solutes such as protein/sugars
coat proteins, helps with structure
What is receptor-mediated endocytosis
specialized pinocytosis where receptors take up specific solutes that can take up low-concentration in bulk
what are lysosomes
membrane-bound organelles made by rER and Golgi body, the interior is acidic/would kill cell but needed for enzyme activity
what is the function of lysosomes
they degrade lipids, carbohydrates and nucleic acids- products into cell
what is autophagy
digesting and recycling unwanted cellular material
what are vacuoles
large vesicles dervied from rER and Golgi
food vacuoles-phagocytosis
