Biology Questions and Answers

(Greg DeLong) #1

Biology Questions and Answers


separate the daughter cells. Plant cells
thus present centrifugal cytokinesis.
The phragmoplast has “failures”, or


pores, to permit cytoplasmiccommunications between the daughter (^)
cells. These openings are called
plasmodesms.



  1. Why is it important for
    chromosomes to be
    condensed during mitosis and
    decondensed during
    interphase?


During mitosissolved is the correct separation o the main problem fto be
chromosome cells. If chromosomes wsets between daughterere


decondensed long tiny fwould be dispersed in cytoplasmibers of DNA after (^)
the karyotheca breaking and
chromosomes coorganized and pulled by the spindleuld not be easily (^)
fibers.
During interphase the function ochromosomes, i.e, of DNA molecules, isf (^)
the synthproteins. Foesis of RNA and thus ofr this task it is necessary (^) for
functional molecular regions to be
decondensed (these regions form theeuchromatin). During interphase in
addition DNA replication occurs as a
preparatory step process it is fundamental for thefor cell division. I n this
exposition of DNA molecules to serve as
templates to new DNA cproduction. hains under



  1. How does the quantity of
    genetic material vary within
    the cell during the sequential
    phases of the cell cycle?


The first period of the first phase(interphase) of the cell cycle is th (^) e G1,
followed by S and G2 amitotic phase. nd then by the
In G1 the ploidy (the quantity of DNAmolecules in the cell) can be
represented by the formula 2n (n is the
number of DNA moleculcell of a given species). In S DNAes in a gamete
duplicates and the quantity of genetic
material ithat quantity isncreases fr constant:om 2n 4n. After thto 4n. In G2e
mitotic phase the quantity of genetic
material ddaughter cell.ecreases to 2n in each



  1. What are the differences
    between astral and anastral
    mitosis?


Astral mitosisformation of the aster, a is that in which thestructure madre is (^) e
by the centriolthat in which tes. Anastralhere is no formatio mitosisn of is (^)
the aster; it occurs in cells without
centrioles, like pplants). lant cells (superior



  1. Can mitosis occur in
    haploid (n) cells? And in
    triploid cells?
    The mitotichaploid (n) cells, diploid (2n) cells, cell division can occur i n
    triploid (3n) cells, etc. Mitosis is a
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