Advanced Biomaterials. Please answer 8.2(a) and (b) only
Consider a material for a vascular graft application with proteins adsorbed to its surface and a second material with proteins covalently attached to its surface. For which material would you expect the protein layer to be more stable under flow conditions similar to those found in a blood vessel? Why? You are performing an in vitro experiment in which you will expose a material you are considering for a medical device to synovial fluid, which contains the proteins albumin, transferrin, and IgM at concentrations of 5, 0.5, and 0.05 mg/ml, respectively. Each of these components has a particular affinity for your material, with IgM being the highest and albumin being the lowest. Describe the kinetics of protein adsorption to your material and how the surface concentration of each protein will change with time. Subsequently in the experiment, more albumin is added to the synovial fluid. What effect will this have on the proteins adsorbed to the surface? The graph below shows the amount of IgM adsorbed to the material surface as a function of time. What will happen on the material surface with the addition of more IgM?
Bacteria in a hot spring at 80 degrees celsius would be expected to have ______________ in their cell membrane
high proportions of saturated phospholipids
high proportions of unsaturated phospholipids
an equal ratio of saturated to unsaturated phospholipid
Question 7
Membrane proteins have an important role in membrane fluidity
True
False
Question 8
The HIV virus can't attach to cells that have a mutation in the CCR5 gene and so such individuals are resistant to HIV. What population of people have a higher incidence of the mutant CCR5 gene and why?
europeans because their ancestors survived the bubonic plague
North Americans because their ancestors survived small pox
europeans because they have a longer evolutionary past with HIV
Africans because they have a longer evolutionary past with HIV
Question 9
Nematode trapping fungi have ______________ molecules called ______________ that recognize specific carbohydrates on the surface of the nematode worms. This is how a fungus can recognize that its prey, the nematode worm, has wriggled into the loop. Write two words on lowercase separated by a space with no other syntax
Question 10
Diffusion requires energy
True
False
Question 11
The net direction of molecule movement when molecules diffuse is
down their concentration gradient
random directions
Question 12
In osmosis, water molecules from a solution of higher solute concentration cross a semi-permeable membrane into a solution of lower solute concentration?
True
False
Question 13
Which best defines osmosis?
In osmosis, water from a solution of lower solute concentration move across a semi-permeable membrane into a solution of higher solute concentration?
In osmosis, water from a solution of higher solute concentration move across a semi-permeable membrane into a solution of lower solute concentration?
Question 14
Animal cells placed into a hypotonic solution would most likely?
lyse (burst)
shrink
remain unchanged in size
Question 15
Glucose and amino acids move into cells via carrier proteins, the same protein can move glucose or amino acids
True
False
Question 16
ATP powered pumps move substances into and out of cells by diffusion?
True
False
Question 17
For every 3 Na ions moved out, 2 K ions are moved into a cell by one cycle of the sodium-potassium pump.
True
False
Question 18
Bulk transport of fluid and any of the substances within that fluid is called
