There are many well-known mutant forms of Hb. These forms are usually named after the region where they are first identified. Hb 'Philly' is a form of hemoglobin that is destabilized by having an F substitute for a Y in the alpha-subunits. The Y normally participates in the hydrogen-bonded network that helps to knit together the alpha1-beta1 interface. Would we say that this mutation destabilizes 1', 2', 3' or 4' structure? Pick one (the best answer) and explain why F causes this problem.

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.

answer: carbon 14 can only be used to determine the age of the organisms that were once living, and igneous rocks are non living.

explanation:

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.