In mitosis when does crossing over occur

Subject optional. Email address: Your name:. Possible Answers: Crossing over occurs in metaphase when all the chromosomes are aligned in the middle of the cell. Correct answer: Crossing over does not occur in mitosis. Explanation : Mitosis is cellular cloning. Report an Error. Possible Answers: G2. Correct answer: Metaphase. Explanation : Metaphase is characterized by the lining up of chromosomes along the "metaphase plate," an imaginary line that divides the cell in half. Possible Answers: Mitosis will generate two daughter cells with the same genetic material from the parent cell, while meiosis will generate 4 daughter cells with half the genetic material from the parent cell.

Meiosis only occurs in humans while mitosis occurs in every living organism. Mitosis does not generate any new cell while meiosis does. The terms mitosis and meiosis can be used interchangeably when explaining cell division. Correct answer: Mitosis will generate two daughter cells with the same genetic material from the parent cell, while meiosis will generate 4 daughter cells with half the genetic material from the parent cell. Explanation : There are many ways that mitosis and meiosis differ, in this question we are primed to look at the differences in the end products of each type of cell division.

Which stage of mitosis exhibits chromatids lining up on the equatorial plate? Possible Answers: Metaphase. Explanation : Prophase- spindles forming, chromosomes condense, and the nuclear membrane begins to break down Prometaphase- microtubules grow Metaphase- chromatids are lined up in the center of the cell on the equatorial plate Anaphase- the two chromatids of the chromosome are pulled apart at the centromere Telophase- new nuclear membranes form around each set of chromosomes, the spindles break down, and chromosomes decondense.

Possible Answers: Telophase. Correct answer: Anaphase. Which stage of mitosis exhibits the spindles forming and chromosomes condensing? Possible Answers: Anaphase. Correct answer: Prophase. Possible Answers: Premetaphase, metaphase, anaphase, telophase, interphase, cytokinesis, prophase. Interphase, Metaphase, premetaphase, anaphase, cytokinesis, telophase, prophase.

Prophase, premetaphase, interphase, anaphase, telophase, metaphase, cytokinesis. Interphase, prophase, premetaphase, metaphase, anaphase, telophase, cytokinesis. Interphase, prophase, telophase, premetaphase, cytokinesis, metaphase, anaphase. Correct answer: Interphase, prophase, premetaphase, metaphase, anaphase, telophase, cytokinesis. Explanation : Interphase would be first as this is the part of the cycle cycle that the cell prepares to enter Mitosis.

At which phase of mitosis are the chromosomes separated and move to each side of the cell? Explanation : Anaphase is where the duplicated chromosomes split, disconnected at the centromere, and each sister chromatid is moved towards opposite sides of the cells. Telophase is the next phase in mitosis. List two things that occur during this phase. Possible Answers: The spindles begin to develop and pull each set of chromosomes to opposite sides of the cell.

Chromosomes are lined up in the middle of the cell and the nuclear envelope begins to form. Correct answer: Chromosome sets are assembled at opposite ends of the cell and a nuclear envelope forms around the chromosomes. Explanation : Important indications that the cell is in telophase are that the chromosomes have been moved towards the opposite sides of the cell.

What term refers to the cell splitting into two daughter cells? Joan E. Bailey-Wilson, Ph. Featured Content. Introduction to Genomics. Polygenic Risk Scores. However, these two processes distribute genetic material among the resulting daughter cells in very different ways.

Mitosis creates two identical daughter cells that each contain the same number of chromosomes as their parent cell. In contrast, meiosis gives rise to four unique daughter cells, each of which has half the number of chromosomes as the parent cell.

Because meiosis creates cells that are destined to become gametes or reproductive cells , this reduction in chromosome number is critical — without it, the union of two gametes during fertilization would result in offspring with twice the normal number of chromosomes!

Apart from this reduction in chromosome number, meiosis differs from mitosis in yet another way. Specifically, meiosis creates new combinations of genetic material in each of the four daughter cells.

These new combinations result from the exchange of DNA between paired chromosomes. Such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation.

Finally, unlike mitosis, meiosis involves two rounds of nuclear division, not just one. Despite this fact, many of the other events of meiosis are similar to those that occur in mitosis. For example, prior to undergoing meiosis, a cell goes through an interphase period in which it grows, replicates its chromosomes, and checks all of its systems to ensure that it is ready to divide.

Like mitosis, meiosis also has distinct stages called prophase, metaphase, anaphase, and telophase. A key difference, however, is that during meiosis, each of these phases occurs twice — once during the first round of division, called meiosis I, and again during the second round of division, called meiosis II.

As previously mentioned, the first round of nuclear division that occurs during the formation of gametes is called meiosis I.

It is also known as the reduction division because it results in cells that have half the number of chromosomes as the parent cell. During prophase I , the chromosomes condense and become visible inside the nucleus.

Because each chromosome was duplicated during the S phase that occurred just before prophase I, each now consists of two sister chromatids joined at the centromere. This arrangement means that each chromosome has the shape of an X.

Once this chromosomal condensation has occurred, the members of each chromosome pair called homologous chromosomes , because they are similar in size and contain similar genes , align next to each other. At this point, the two chromosomes in each pair become tightly associated with each other along their lengths in a process called synapsis.

Then, while the homologous chromosomes are tightly paired, the members of each pair trade adjacent bits of DNA in a process called crossing over , also known as recombination Figure 1.

This trading of genetic material creates unique chromosomes that contain new combinations of alleles. During meiosis II , the two cells once again cycle through four phases of division. Meiosis II is sometimes referred to as an equational division because it does not reduce chromosome number in the daughter cells — rather, the daughter cells that result from meiosis II have the same number of chromosomes as the "parent" cells that enter meiosis II.

Remember, these "parent" cells already have half the number of chromosomes of the original parent cell thanks to meiosis I. This page appears in the following eBook. Aa Aa Aa. What happens during meiosis I? Prophase I. Figure 1: Recombination is the exchange of genetic material between homologous chromosomes. At the end of prophase I, the nuclear membrane finally begins to break down. Outside the nucleus, the spindle grows out from centrosomes on each side of the cell.

As in mitosis, the microtubules of the spindle are responsible for moving and arranging the chromosomes during division. Metaphase I. Figure 2: Near the end of metaphase I, the homologous chromosomes align on the metaphase plate. Each chromosome looks like an elongated X-shaped structure.

In the pair of chromosomes at top, the chromosome at left is mostly green, but the lower region of the right chromatid is orange.

The chromosome at right is mostly orange, but the lower region of the left chromatid is green. A second pair of chromosomes exhibiting the same pattern of coloration on their arms is shown below the topmost pair. Mitotic spindles are located at each side of the cell. Each spindle apparatus is composed of several white lines, representing fibers, emanating from two oval-shaped structures, representing centrosomes. The fibers attach the centrosomes to the centromeres of each chromosome.