Neuroscience Flashcards
What are the SNARE proteins ?
• v SNARE on vesicle
- synaptobrevin (VAMP)
• t SNARE on presynaptic membrane
- syntaxin and SNAP-25
What is synaptotagmin
A protein associated with a synaptic vesicle where Ca2+ ions bind to it allowing the vesicle to move closer to the presynaptic membrane
What does phospholipase C do?
Once stimulated from a receptor protein by g -protein activation, the enzyme breaks down phospholipids in the membrane to DAG and iP3
DAG activates protein kinase C
iP3 stimulates release of Ca2+ from ER
Name the regions of the brain not enclosed by the blood brain barrier
- area postrema
- median eminence
- posterior pituitary
- pineal gland
- subfornical organ
- Lamina terminalis
Name the functions of cerebral spinal fluid
- cushions and protects CNS from trauma
- mechanical buoyancy and support for the brain
- reservoir for nutrients
- removes metabolic waste
- protects against changes blood pressure
- involved in intracerebral transport (eg hypothalamic releasing factors +pineal secretions to reach pituitary gland)
True or false
Glyceryl trinitrate is completely metabolised by 1st pass metabolism
True
True or false
Tubocurare is a lipid soluble drug
False
True or false
Metabolism of drugs consists of phase 1 ‘functionalisation’ and phase 2 ‘conjugation’
True
True or false
Lipid solubility is a product of physiochemical properties of the drug and pH of the environment
True
What are sensory nerves also termed as?
Sensory afferent nerves
what are the functions of phospholipid cell membranes?
- cell-cell recognition
- sites for recognition of chemical messengers
- control exchange of solutes
- defines shape
- structural integrity
- facilitate cellular locomotion
what is the role of cholesterol in plasma membranes?
increase flexibility,
reduce fluidity
lower permeability to water soluble molecules
what is a lipid raft?
found on plasma membranes, they contain a lot of cholesterol and sphingolipid molecules .
involved in transportation of proteins in small vesicles
which membrane protein is attached to the plasma membrane only by non- covalent bonding to other membrane proteins?
a) integral
b) transmembrane
c) peripheral
peripheral
what are integral membrane proteins?
a protein exposed to only one side of the plasma membrane and interact with the plasma membrane (either with an alpha helix chain, lipid groups or tight binding to other proteins)
Which molecule is impermeable to plasma membranes?
a) water
b) urea
c) bicarbonate ions
d) ethanol
e) oxygen
c) bicarbonate ions because they are charged ions
what are uniport, symport and antiport transport protein?
uniport: one way transport of a single molecule
symport: two molecules transported simultaneously
antiport: two molecules transported in opposite directions
what type of transport protein is the glucose transport protein? (symport or antiport) and which molecule is it coupled with?
symport coupled with sodium ions
the glucose facilitated diffusion is dependent on sodium ion concentration gradient which is maintained by sodium ion pumps
give an example of an antiport transporter protein
sodium-potassium ATPase pump
3 sodium ions pumped out of cell, 2 potassium ions pumped into cell
what are types of cell junctions?
tight junctions
adherens junctions
hemidesmosomes
desmosomes
gap junctions
give an example of location of tight junctions and their function
epithelial cells in small intestines
seal cells together creating a barrier
what is the difference between phagocytosis and pinocytosis?
phagocytosis : “cellular eating” ingestion of large particles
pinocytosis: “cellular drinking” ingestion of fluid and solutes
what is receptor mediated endocytosis and where does it occur?
uptake of molecule once bound to receptors on plasma membrane - triggers endocytosis - example of cholesterol,LDLs uptake
what is osmotic pressure?
force applied to stop osmosis