Topics to choose among: And please suggest other topics.1) Bone formation and osteoporosis. Osteocytes cause calcium phosphate to crystallize among collagen fibers, but cannot be said to "secrete" calcium phosphate crystals, because these are never present inside the cells. For unknown reasons, osteocytes always bud off thousands of tiny vesicles of membrane at the locations where bone will form. Bone is constantly destroyed by a kind of multicellular macrophage cell called osteoclasts (which secrete acid and enzymes) and re-formed by osteocytes, but in old age (and also in astronauts) net reductions in bone occur, either because of more active osteoclasts and/or less active osteocytes. More bone is formed in bones (Strong loads somehow cause more bone to be formed at the locations, and also the directions where bones and parts of bones "feel" the most stress. But it isn't known whether this detection of force is by piezoelectric voltages.)
2) Nerve basis of memory and/or thought. You can report on neural connection studies, behavioral studies, PET scanning images, results of damage to the hippocampus and/or the cerebral cortex, hypotheses that have been proposed, computer and mathematical "models".
3) Eye brain connection, and other map-like neural projections. Long assumed to be caused gradients of cell-cell adhesion proteins, some unexpected proteins have been discovered ("ephrin", and "ephrin receptors") which stimulate detachment of cell adhesions, in proportional to the local concentrations of ephrins multiplied by the local concentrations of ephrin receptors. When two eyes innervate the same brain, they form alternating stripes. This occurs in stereo vision, and also when two optic nerves are surgically re-routed to the same part of a brain (in frogs).
4) Artery-vein connections and boundaries, also are turning out to be controlled by ephrin", and "ephrin" receptors, and a former UNC graduate student has made several of the major discoveries about this.
5) Alzheimer's and/or mad cow disease and prions. How are they related, and what are the mechanisms?
6) Is there really a causal connection between telomeres and aging? In other words, is the deterioration of various cells that occurs in aging because telomeres fail to replace the ends of chromosomes? Or are these two kinds of deterioration, that look somewhat alike, but which actually have different causes?
7) Altruism & Eusocial Behavior: Was W. D. Hamilton right? Does haplo-diploid sex determination really favor evolution of bee colonies, ant colonies, etc.? What about termites, Naked Mole Rats, and the eusocial shrimp studied by Emmett Duffy? To what extent does E. O. Wilson now doubt that the ant colony way of life evolved because of haplo-diploid sex determination?
8) Are cancer cells really less adhesive than their normal equivalent cells, from which they developed? Has weakened contractility sometimes been misinterpreted as weakened adhesion? What aspect of adhesion changes: Strength, area, distribution, "work of adhesion" if there is such a thing?
9) Has the "Clock and Wave-Front" theory at last been conclusively proven true, including the identification of the proteins that form the moving gradient and the oscillating "clock"?
10) What is the causal difference between "Regulative Development" (as in mammals) that allows separated early embryonic cells to develop as identical twins, as compared with "Mosaic Development" (as in nematodes and flies) (in which separated early embryonic cells develop into parts of the anatomy)?
11) In embryos whose development is regulative, what mechanism(s) reduce the sizes of the parts in proportion to reduction in size of cytoplasm or tissues to be subdivided?
12) Formulate some other unsolved problem (and ask me to approve it).
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