Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
Membrane elements
|
Integral membrane proteins, peripheral membrane proteins, glycoproteins/glycolipids that serve as signalling structures. Encapsulation referred to as the glycocalyx
|
|
|
Membrane proteins function
|
Transport proteins: channel proteins, carrier proteins, pumps; receptors; structural/anchoring proteins
|
|
|
Ribosome locations
|
Free ribosomes, mitochondrial ribosomes, RER
|
|
|
free ribosomes
|
exhibit polysomal action, synthesize 80% of mitochondrial proteins, responsible for cellular proteins besides those in the Golgi apparatus, lysosomes, secretory granules, and the plasma membrane
|
|
|
SER functions
|
lipid and steroid metabolism, detoxification, glycogen metabolism, and Ca++ regulation in structures called sarcoplasmic reticulum.
|
|
|
RER functions
|
site of synthesis for secreted proteins, lysosomal, plasma membrane, and Golgi proteins are also made here
|
|
|
regions of Golgi
|
cis: point of arrival, and initial modifications; medial: modification; trans: final changes, transport
|
|
|
functions of Golgi
|
modification of proteins: sugar residues, sulfate, or phosphate; sorting and packaging of proteins
|
|
|
Golgi targets
|
secretory vesicles (e.g. pancreatic acinar cells), lysosomes (principal signal mannose-6-phosphate), plasma membrane
|
|
|
Lysosome classifications
|
Primary: not received substrate
Secondary: fusion of target and lysosome Lipofuscin granules: senescent vessels |
|
|
Constitutive Pathway
|
proteins not marked for granules or lysosomes are transported directly to the plasma membrane
|
|
|
I - cell disease
|
mucolipidosis: enzyme responsible for mannose-6-phosphate signal is non-functional, and lysosomal proteins are secreted into intercellular space
|
|
|
Peroxisome function
|
oxidation of molecules, esp. long chain fatty acids, and conversion of ethanol
|
|
|
adrenoleukodystrophy
|
X-linked, progressive brain damage and adrenal gland failure. Caused by accumulation of lipids in the brain and adrenals.
|
|
|
Zellweger syndrome
|
congenital disease, mutations in proteins responsible for transport of peroxisomal enzymes prevent delivery. Affects brain development and myelin sheath formation
|
|
|
Mitochondrial features
|
mobile, amorphous (spheres, rods, filaments, spirals), double membrane energy centers, important in the oxidation of pyruvate and small fatty acids
|
|
|
mitochondrial membranes
|
outer membrane has pores for ion exchange; inner membrane: much thinner, folded into cristae, tubulovesicular; Matrix contains soluble enzymes for Krebs, transcription, mitochondrial DNA, and m ribosomes, electron dense granules for Ca++ storage
|
|
|
Chromatin types
|
Euchromatin: metabolically active, lightly condensed
Heterochromatine: highly condensed |
|
|
centromere
|
region of chromosome where sister chromatids join together by a kinetochore
|
|
|
Nucleolus regions
|
Fibrillar centers: DNA loops with rRNA genes and transcription factors
Dense fibrillar component: ribosomal genes being translated and large amounts of RNA Granular component: site for ribosomal assembly |
|
|
Cytoskeleton filament types
|
Actin cytoskeleton (thin filaments)
Microtubules Intermediate filaments |
|
|
thin filament structure/functions
|
F-actin polymers with polarity, thin sheath called cortex
prevents deformation, transmit forces, and restricts organelle movement and lateral motion of integral proteins |
|
|
Microtubules structure/functions
|
a-tubulin and B-tubulin cylinders. (+) end grows faster than (-) end. Involved with organelle and vesicle movement, mitotic spindle and chromosome movement, flagella/cilia movement
|
|
|
microtubule motor proteins
|
Dyneins: towards (-) end, cilia flagella movement
Kinesins: move towards (+) end |
|
|
microtubule organization
|
core axoneme of 9 doublets around a central pair. dynein arms grip doublets in sequence, expending ATP.
Cilia and flagellum use 9 triplet pairs without a center microtubule organizing center (MTOC) consisting of two centrioles gives rise to almost all microtubles |
|
|
Types of intermediates
|
Lamins: meshwork in nuclear envelope
Keratins: epithelial cells Vimentin: connective tissues Desmin: muscle cells Glial Fibrillary Acidic Protein: glial cells Neurofilaments: neurons |
