GOOD LUCK EVERY BODY :-)
For the Fall 2012 Exam, we don’t need to know the 1st question right? With the
picture on it
^that picture is from Wednesday so I don’t know if we are responsible for that on
the exam because the picture shows what the DNA looks like when not wrapped
around the histone.
I think it is a picture of DNA spilling out of a bacterium. If that is the case, we have seen
the picture before and he did talk about it.
Yeah but I’m pretty sure it was after lamina… also. the 2nd question… “show the
structure/indicate composition of the nuclear fibrous lamina.” like… what can we
possibly draw other than the 2 proteins (lamin A and lamin B)...
We can draw the two bilayers and show that fibrous lamina is attached to the inner layer
by bonding to intermembrane proteins.
What’s “conventional thin section transmission electron microscopy”? Is that the thing where
you add an aldehyde to a cell to kill it, wash it with alcohol, stain with OsO4 for better
visualization and then slice and look at it with an electron microscope? Btw this is #6 on the fall
Outline how you might test the hypothesis that a protein extracted from the nuclei of frog oocytes would
accumulate in the nucleus if introduced into the cytoplasm of another cell, while a non-nuclear protein
(such as albumin from blood) would not accumulate in the nucleus under similar experimental conditions.
Wouldn’t this just be like the experiment where we label the proteins with gold?
Thats what I’m thinking. Or, could you put a nuclear localization signal on the non-nuclear
protein and see if it will enter through the NPC? That doesn’t really test the hypothesis though. I
think the answer is that you just put gold beads on the molecules and watch where they go/stay.
GOLD BEADS ON tRNAs attached to molecules with NLS
You watch it with...electron microscopy?
Yeah. I guess… Just making an educated guess here
Anybody know wtf a 100Angstrom fiber is???
I’m pretty sure that’s from something we haven’t gotten to yet. Correct me if I’m wrong. I believe we
discussed it last lecture comparing it to 300 so it wont be on the test.
^Oh ok that makes sense. I didn’t go to lecture on wednesday. Thanks
Do any of you guys know how to find the minimum number
of amino acids in a transmembrane helical segment? Its 20..
1.5Ax 20 is about the length of a fatty acid chain (16-18
1 On the fall 2011 exam it talks about a karyotype analysis. We
did not do that, right?
Yeah, what the hell is that… it says “In the karyotype analysis discussed in lecture, why
should cells to be examined have to be maintained for a period in the presence of
colchicine?” I don’t think we need to worry about it
Good. Glad someone else has no idea what that is. Makes me slightly less terrified.
Yeah because I take really detailed notes and it would have at least rung a bell in my
head. I looked up colchicine and it has nothing to do with what we’re learning
Also. do we need to study the 100/300 Angstrom fibers? Dr Ades talked about that after the
nuclear lamina so I’m guessing no….
“how is the breakdown of the nuclear envelope at the onset of mitosis linked with the
modifications of elements of the lamina?”