BIOL 101 Lecture Notes - Lecture 15: Sister Chromatids, Homologous Chromosome, Meiosis

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29 Nov 2016

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In animals, the cells that are produced in meiosis--thus getting half the number of chromosomes--are always reproductive cells, called gametes: such a reduced-chromosomal state are said to be haploid: possessing a single set of chromosomes; referred as n. Diploid: possessing two sets of chromosomes; referred as 2n. Meiosis: a process in which a single diploid cell divides to produce four haploid cells. End of interphase - prior to meiosis: dna has already duplicated. Homologous chromosomes link as they condense, forming tetrads: when homologous chromosomes pair up; ex: paternal 6 and maternal 6. Another thing occurs at the same time -- crossing over: a process, occurring during meiosis, in which homologous chromosomes exchange reciprocal portions of themselves: metaphase i. Microtubules move homologous chromosomes to metaphase pate. Another occurs -- independent assortment: the random distribution of homologous chromosome pairs during meiosis: anaphase i. Microtubules separate homologous chromosomes (sister chromatids remain together: telophase i. Two haploid daughter cells result from cytokinesis.

Related Questions

Consider each of the following statements.

In meiosis, the chromosomal material doubles during the lastpremeiotic interphase.

The greater the number of chromosome pairs, the greater is theeffect of meiosis in producing genetically distinct gametes.

The diploid number of chromosomes is half the haploidnumber.

A cell that will not divide again remains in the GÂ2 stage ofinterphase.

The correct sequence of events during meiosis is: synapsis ?dyad formation ? chiasma formation

In an organism with n = 3, there is a 1 in 8 probability of agamete with all maternally derived chromosomes contributing to theproduction of a zygote.

An organism with n = 3 can produce 8 different kinds of gametesin relation to combinations of maternal and paternalchromosomes.

Separation of sister chromatids occurs during anaphase I ofmeiosis and is the physical basis for the law of independentassortment.

A single diploid cell that undergoes meiosis in the male testiswill produce 4 genetically different gametes if crossing-over isignored.

The independent alignment of different tetrads at metaphase I ofmeiosis is the physical basis of the law of independentassortment.

If a diploid cell has 20 pairs of chromosomes, there will be 10tetrads during prophase I of meiosis.

If a diploid cell has 20 pairs of chromosomes, there will be 20bivalents during prophase I of meiosis.

If a diploid cell has 20 pairs of chromosomes, there will be 80chromatids present during metaphase of mitosis.

If a diploid cell has 20 pairs of chromosmes, the organism canmake 20² types of gametes if crossing-over isignored.

Segregation of sister chromatids occurs during anaphase I ofmeiosis and is the physical basis of the law of segregation.

For an individual with a diploid number of 30 chromosomes, therewill be 60 chromatids at metaphase I of meiosis.

For an individual with a diploid number of 30 chromosomes, therewill be 15 tetrads at metaphase II of meiosis.

yellowpig507

PLEASE HELP

Which of the following statements are true?

a. In meiosis, the chromosomal material doubles during the lastpremeiotic interphase.

b. The greater the number of chromosome pairs, the greater isthe effect of meiosis in producing genetically distinctgametes.

c. The diploid number of chromosomes is half the haploidnumber.

d. A cell that will not divide again remains in theGÂ₂ stage of interphase.

e. The correct sequence of events during meiosis is: synapsis âdyad formation â chiasma formation

f. In an organism with n = 3, there is a 1 in 8 probability of agamete with all maternally derived chromosomes contributing to theproduction of a zygote.

g. An organism with n = 3 can produce 8 different kinds ofgametes in relation to combinations of maternal and paternalchromosomes.

h. Separation of sister chromatids occurs during anaphase I ofmeiosis and is the physical basis for the law of independentassortment.

i. A single diploid cell that undergoes meiosis in the maletestis will produce 4 genetically different gametes ifcrossing-over is ignored.

j. The independent alignment of different tetrads at metaphase Iof meiosis is the physical basis of the law of independentassortment.

k. If a diploid cell has 20 pairs of chromosomes, there will be10 tetrads during prophase I of meiosis.

l. If a diploid cell has 20 pairs of chromosomes, there will be20 bivalents during prophase I of meiosis.

m. If a diploid cell has 20 pairs of chromosomes, there will be80 chromatids present during metaphase of mitosis.

n. If a diploid cell has 20 pairs of chromosmes, the organismcan make 20² types of gametes if crossing-over isignored.

o. Segregation of sister chromatids occurs during anaphase I ofmeiosis and is the physical basis of the law of segregation.

p. For an individual with a diploid number of 30 chromosomes,there will be 60 chromatids at metaphase I of meiosis.

q. For an individual with a diploid number of 30 chromosomes,there will be 15 tetrads at metaphase II of meiosis.

taupecicada359

Which of the following statements are true. CHALLENGEQUESTION:

a. In meiosis, the chromosomal material doubles during the lastpremeiotic interphase.

b. The greater the number of chromosome pairs, the greater isthe effect of meiosis in producing genetically distinctgametes.

c. The diploid number of chromosomes is half the haploidnumber.

d. A cell that will not divide again remains in the GÂ2 stage ofinterphase.