During meiosis, a defect occurs in a cell that results in the failure of microtubules, spindle fibers, to bind at the kinetochor
es, a protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart. Which of the following is the most likely result of such a defect?A) New microtubules with more effective binding capabilities to kinetochores will be synthesized to compensate for the defect.B) Excessive cell divisions will occur resulting in cancerous tumors and an increase in the chromosome numbers known as polyploidy.C) The defect will be bypassed in order to and ensure normal chromosome distribution in the new cells.D) The resulting cells will not receive the correct number of chromosomes in the gametes, a condition known as aneuploidy.
The resulting cells will not receive the correct number of chromosomes in the gametes, a condition known as aneuploidy.
Explanation:
Formation of functional microtubule spindle fibers and their attachment to kinetochores of chromosomes is required to ensure their alignment st the cell's equator during metaphase. During anaphase, shortening of these microtubules pulls the chromosomes to the opposite poles. These events ensure the distribution of the correct number of chromosomes among the daughter cells. The presence of defective microtubules would not allow proper distribution of chromosomes to the daughter cells and would result in the presence of an abnormal number of chromosomes (aneuploidy).
You can tell that rocks are older or younger depending on if other layers overlap. B is the oldest because all the others cover it, C is the second youngest because D and A overlap it. From what I could tell, when I took the test, it was either A or D, neither overlap each other so I was not sure so I guessed A and got it right. Though it could be looked at that A is smaller than D since its still growing and building.
Most diving birds have (relatively) long necks and shorts legs, although their necks aren't as long as say herons, storks or egrets. Take the common loon for instance. Their necks can be up to half as long as their bodies but their legs are so short and set so far back that they are very awkward on land.
