Exam iii Flashcards
What is the function of IF and Where is it located?
Intermediate Filaments have great strength to withstand mechanical stress and are found in cytoplasm in most animal cells within the nucleus(nuclear lamina) and cell-cell junction (desmosomes) for anchor
What are keratin filaments and its function? Wha tis the mutated disease associated with it?
Keratin filaments are the most diverse class of IF and its ends are anchored to desmosomes. Mutation of keratin filaments lead to epidermolysis bullosa simplex
What are the 4 classes of IF, what types of cells are they found, and where in the cells are they located?
Keratin filaments(epithelial cells), vimentin and vimentin-related filaments (connective tissue cells, muscle cells, glia cells), neurofilaments (nerve cells), nuclear lamin (nuclear envelope)
Which classes of IF are found in the cytoplasm? Where is the fourth one?
Keratin filaments, vimentin and vimentin-related filaments, and neurofilaments are found in the cytoplasm. nuclear lamin is found in the nucleus
What is the function of pectin?
pectin is an accessory proteins that cross link filaments to microtubules, actin filaments, and to desmosomes.
Which IF constructs the nuclear lamina? What happens when it is dephosphorylated or phosphorylated? Which protein is responsible to phorsphylate or dephosphorylate?
Lamina is a class of IF that construct nuclear lamina when dephosphorylated by phosphates and disassemble by phosphorylated by kinases.
What is the mutated disease with nuclear lamin?
defects of nuclear lamin are associated with progeria that causes premature aging.
Where are new phospholipids manufactured?
On the cytosolic surface of the er
What are some of the function of membrane proteins?
Transporters and channels
Anchors
Receptors
Enzymes
Which fixes the bilayer to have phosophatidylserine and phsophatidylethanolamine to be on the cytosolic side
The golgi membrane
What are the different ways that proteins can be associated with the lipid bilayer
Transmembrane that are partially in and out of the membrane or completely in
Some are anchored to only one side of the bilayer
Some are lipid link to the inside or outside
Otherwise are protein attached
What is the difference between integral membrane proteins and peripheral membrane proteins
Proteins that are directly attached to the membrane are integral membrane proteins. The rest are peripheral membrane proteins
What are detergent?
Amphipathic lipid like molecule with only one tail
What is the difference between glycoproteins and proteoglycans?
Glycoproteins have short chains of sugar( oligiosaccharides) and proteoglycans have one or more long chains of polysaccharides. But they are all found on the outside of membrane and can absorb water
What are transporters
Shift small organic or inorganic a molecules from one side of the membrane to the other by. Changing shape
List the rate of diffusion from fastest to slowest and examples . Small nonpolar uncharged Polar molecule charged molecule ions
Small non polar like oxygen carbon dioxide
Small unchanged polar molecule like water ethanol glycerol
Large uncharged polar molecules like amino acids glucose nucleosides
Iona like H K Na MG
What is the difference between channels and transporters
Channels discriminate based on size and elective charge
Transporters transfers ion or molecules that fit onto specific binding sites
What is the flow of concentration gradient
Move from an area of high concentration to low concentration
What are the different types of couple pumps and it’s function
Symport pumps both solutes in the same direction
Antiport moves solutes in opposite direction
Uniport one type of solute and not coupled
True false
Most ion channels are gated
True
What does the nernst equation calculate
The membrane potential during resting of ion concentration on either side
What influences the open and closing of voltage gate channels ligand gate channel and mechanically gates channels
Opening and closing of voltage gate channels is controlled by membrane potential
Ligand gates channel controlled by the binding of the ligand
Mechanically gates channel is controlled by a mechanical force applied to the channel
Give an example of mechanically gates channel
Auditory hair cells
What are the three confirmation of voltage gate Na channel
Closed. Inactive where Na is not allowed in but Neuron is still being depolarized. Open
What are cellulose microfibrils
Polysaccharide cellulose and some structural proteins that bind together to form a complete structure that resist repression and tension
Where is collagen found
In bone tendon and skin
What are collagen fibrils and collagen fibers
Collagen fibrils are thin cables that pack together to form collagen fibers
What is fibroblast
Connective fissure cells the make and live the extracellular matrix
What is the purpose of Intergrin
A cell attaches to fibrinectin, a linkage to collage, by Integrins
What is the difference between apical and basal surface of epithelial sheer
Apical surface is free to the air or watery fluid. The basal surface is attached to the basal lamina that is attach to a Tough sheet of extracellular matrix
Which proteins form right junction
Claudine and occludins
What is adherens junction
Join actin bundles of nearby cells
What are desmosome
Join nearby IFs together
