Cystology Flashcards
What is the plasma membrane made of ?
phospholipids + proteins + cholesterol
What is the function of cholesterol?
maintains fluidity + increases stability
What is the function of glycoproteins?
provide shape, cell adhesion, signaling + transport
What is the function of glycolipids?
stabilize the membrane structure
What is the function of the rough ER?
protein translation + polypeptide formation
What is the function of the smooth ER?
steroid hormone production + detox
What is the function of the golgi apparatus?
protein modification + sorting (post office of cell)
What is the function of lysosomes?
enzymatic break-down of cellular material
What is the function of endosomes?
transport extracellular material
What is the function of peroxisomes?
degrade fatty acids + toxins
What is the name of the inner membrane fold in mitochondria? What is the function?
cristae; increases surface area for increased formation of ATP
What is mitochondria stained with?
rhodamine 123 (immunocytochemical stain)
What is the difference between smooth and rough ER?
rough: has ribosomes needed for protein translation -> results in polypeptide
smooth: NO ribosomes -> found in gonads + liver
What is the golgi apparatus composed of?
stack of cisternae
What is a lysosomal storage disease?
Tay-sachs
What are the type of lysosomes?
phagocytosis -> phagolysosome
endocytosis -> endolysosome
autophagy -> autophagolysosome
What does the residual body contain?
leftover material that COULD NOT be broken down
Endosomes contain material from what?
phagocytosis, pinocytosis, and receptor-mediated endocytosis
What membrane bound organelle contains oxidases?
peroxisomes
What is energy released from oxidation converted into?
heat
Where is the site of ribosome production?
nucleolus
What are the non-membrane bound organelles?
- microtubules, microfilaments, intermediate filaments -> part of cytoskeleton
- centrioles -> cell division + microtubule organization center
- ribosomes -> protein translation + synthesis
What type of subunits make up microtubules?
alpha and beta -> form dimers -> form protofilaments
Are alpha subunits on the plus or minus end?
minus end
Are beta subunits on the plus or minus end?
plus end (growth of microtubule is the fastest on this end)
Where does the microtubule assembly start from?
microtubule organization center = 1 centrosome
What are microfilaments made of?
globular g-actin formed into filamentous f-actin
Which end of the microfilament is the fast growing end?
plus end
Which end of the microfilament is the slow growing end?
minus end
When does polymerization into filaments occur?
when g actin > critical conc.
What are the cytokeratins found in the epithelium?
type 1: acidic
type 2: basic
What is the function of centrosomes?
nucleation site for the formation of microtubules -> MTOC
What is the function of molecular motors?
move organelles + other structures within a cell
What are the major types of molecular motors?
kinesin, dynein, and myosin
What are the functions of kinesin?
- binds microtubules
- moves anterograde = AWAY from nucleus -> towards plus end (beta subunit)
- motor protein
What are the functions of dynein?
- binds microtubules
- moves retrograde = TOWARDS nucleus -> towards minus end (alpha subunit)
- role in ciliary + flagellar movement
What are the functions of myosin?
- binds microfilaments
- moves anterograde = AWAY from nucleus -> towards plus end
How are secondary lysosomes made?
- formed by fusion of primary lysosomes and phagosomes
- formed by sites of active digestion of phagocytosed materials
