Cytoplasm Flashcards
what is the fuzzy coating called?
glycocalyx
what are free ribosomes used for?
synthesis of proteins
where are RER ribosomes located?
- golgi
- lysosomes
- plasma membrane
where are mitochondrial ribosomes located?
20% mitochondrial proteins
where are the small and large subunit manufactured?
nucleoleous and released in cytosol
ER function
synthesis of organic material
which ER is tubular?
SER
SER function
- lipid/steroid metabolism
- membrane formation/recycling
- detox
- glycogen metabolism
- Calcium storage
sarcoplasmic reticulum is where
SER in muscle tissue
RER function
protein synthesis for:
- export
- golgi
- lysosomes
- plasma membrane
where does Golgi receive transport vesicles from?
from RER to the cis-face
what happens in the cis-golgi?
phosphorylation of proteins
what happens in the medial Golgi?
addition of sugar residues
what happens in the trans-golgi?
- protein proteolysis
- lipid and protein sorting
- addition of sugar residues
what are the 3 options for a vesicle leaving the trans Golgi?
- incorporation of new cell membrane
- lysosomes
- secretion (exocytosis)
4 functions of golgi
- modification of proteins
- sorting of macromolecules
- packaging vesicles
- lysosome production
what kind of cells are secretory vesicles usually found in?
pancreatic cells
what receptor is needed for lysosome destination?
mannose-6-phosphate
which destination pathway is common for collagen?
constitutive pathway (cell membrane)
lysosome pH
acidic
what enzymes do lysosomes have?
- proteases
- lipases
- glucosidases
which lysosome has no substrate?
primary
which lysosome fuses with target?
secondary
which lysosome has lipofuscin granules (undigested material)?
senescent lysosomes
what is lysosomal storage disease called?
I-cell disease
what is missing with I-cell disease?
- no sorting signal
- no lysosomal enzymes (mannose-6-phosphate)
what is I-cell disease presentation?
- abnormal skeleton
- restricted joints
- hepatomegaly
- spelnomegaly
which enzymes are oxidative?
peroxisomes
which enzymes make very long chain fatty acids and have a H2O2 byproduct?
peroxisomes
which enzyme degrades H2O2?
catalase
which syndrome has a lack of peroxisomes, no myelin sheath, and early death?
Zellweger syndrome
which syndrome has X-linked, impairs oxidation of fatty acids, causes lipid accumulation in the brain?
Adrenoleukodystrophy
what is the result of Adrenoleukodystrophy?
- dementia
- adrenal failure
what does the mitochondria matrix contain?
its own DNA and enzymes
what is the important protein in the mitochondrial intermembrane space?
cytochrome C = causes apoptosis
what important granules does the mitochondria have?
electron dense granules (calcium storage)
what kind of inheritance involves the mitochondrial DNA?
maternal
how do mitochondrial myopathies manifest?
- proximal muscle weakness
- extraocular muscles
- neuro symptoms
- lactic acidosis
- cardiomyopathy
3 filaments of the cytoskeleton
- thin filaments (actin)
- microfilaments
- intermediate filaments
2 types of thin (actin) filaments
- G actin
- F actin
(G actin becomes F actin)
which actin filament is polymerized
F-actin
what forms the cell cortex?
thin filaments
where are microtubules NOT found?
erythrocytes
which filaments are non-branching hollow cylinders that are polymerized?
microtubules
2 proteins in microtubules
a-tubulin
b-tubulin
which microtubule motor moves to the minus end and beats flagella?
dyneins
which microtubule motor moves to the plus end?
kinesins
microtubule functions
- organelle movement
- chromosome movement
- flagella/cilia
what are the different microtubule higher order structure?
- axoneme
- basal bodies
- MTOC (2 centrioles)
what makes up an axoneme?
- 9 doublets of microtubules
- central pair
- dynein arm
what makes up a centriole?
9 triplets of microtubules
MTOCs are in all cells except which 2 cells?
- neurons
- RBCs
which filaments have no polarity and no motor?
intermediate filaments
6 major groups of intermediate filaments
- Lamins
- Keratins
- Vimentin
- Desmin
- GFAP
- Neurofilament protein
lamins location
nucleus
keratins location
epithelium
vimentin location
connective tissue
desmin location
muscle
GFAP location
glial cells
neurofilament protein location
neurons
intermediate filament functions
- spread tensile forces
- maintain cell architecture
- cocoon for damaged cell
- ion channel protein anchor
- create nuclear lamina
where are the most peroxisomal proteins synthesized?
cytoplasmic ribosomes
