Free Floating Chromatin In The Diploid Cell

2. At the end of meiosis, how many haploid cells have been formed from the original cell?

Anaphase – the chromosomes are divided into single from pair and the chromosomes move to opposite poles

Meiosis is the cell cycle for germ cells (gametes) where they are haploid (n) so that is why they have two sets of phases.

Mitosis and meiosis are similar in several ways and different in others. The similarities include that both processes involve IPMAT. IPMAT is interphase, prophase, metaphase, anaphase and telophase. The parent cells are diploid. They both end with cytokinesis. In Metaphase and Metaphase II, the sister chromatids line up along the center. Then in Anaphase and Anaphase II, these chromatids are split and pulled towards the centrosomes. The differences are that mitosis consists of 1 division while meiosis consists of 2. Four genetically different, haploid sex cells are the products of meiosis and 2 identical, diploid somatic cells from mitosis. Mitosis occurs in all organisms except viruses and meiosis only occurs in plants, animals, and fungi.

Define the term crossing over. (3 points) During meiosis’ prophase the homologous chromatids exchange segments.

A) Meiosis consists of two cell divisions and is broken up into Meiosis I and Meiosis II. At the beginning of the Cell Cycle, in this case there are four chromatids each from the homologous pairs being A, a, B, b. This is the Diploid number (4) meaning it is 2 times the haploid number that will be seen at the end of meiosis II. During the S phase of interphase, the chromatids replicate and reach the end of G2 phase. Now starting meiosis, during the first stage of prophase I the chromosomes condense and pair up through synapsis with their sister chromatids creating AA, aa, BB, bb. After they pair up they go through a process called crossing over, where the homologous chromosomes share a piece of their genetic material with each other. Crossing over allows for the genetic diversity of chromosomes. Now there are four homologous chromosomes Aa, Aa, Bb, Bb, each containing heterozygous alleles because the sister chromatids exchanged genetic information with their homologous pair. During late prophase I, spindle fibers being to form where they will later attach to a homologous chromosomes centromere. The next stage is Metaphase I. During metaphase I, the homologous pairs line up at the metaphase plate, also known to be the center of the cell. The homologous pairs form a tetrad which is considered a group of four homologous chromosomes. These homologous chromosomes orient themselves randomly, which is know as the process of independent

Mitosis: This is the process by which a cell duplicates the chromosomes in its cell nucleus in order to generate two identical daughter nuclei.

Meiosis consists of one DNA replication and two nuclear divisions resulting in 4 daughter cells. The process which provides for genetic variation is crossing over. Crossing over occurs in the early stages when homologous chromosomes move together so that their chromatids form a tetrad. This is called synapsis and allows for the exchange of chromosome sections.

Response Feedback: Meiosis occurs only in replicating gametes or reproducing cells. In phase one, the number of chromosomes is reduced by half but the chromatid pairs remain together. In phase two, the chromatids split apart forming four daughter cells. Non-germ cells such as red blood cells or skin cells undergo mitosis.For more information on this topic, consult:Carol Mattson Porth and Glen Matfin, Pathophysiology, 8th Edition,

Chromosomes line up in different orders (random assortment) so when they go to either new cell on cell might have dominant for one characteristic (e.g. brown eyes), recessive for another (e.g. blond hair), and dominant for a third one (e.g. can roll tongue) whereas the other created cell might be dominant, dominant dominant (brown eyes, brown hair and can roll tongue.

Meiosis is a form of cell division that halves the amount of chromosomes in sexually reproducing organisms (Bernstein et al 2011) to form gametes. In meiotic cell division, DNA replication is followed by two rounds of cell division to create four daughter cells, each with half the amount of chromosomes as the parent. Meiosis is split into two round called Meiosis I and Meiosis II and each round of meiosis is made up of four stages called prophase, metaphase, anaphase, and telophase. The longest, most complex stage of meiosis is Prophase I as it is split into 5 phases called lepotene, zygotene, pachytene, diplotene, and diakinesis (Tworzydlo & et al 2016). In these stages of prophase, chromosome pairing, synaptomenal complex formation, and recombination occur. The formation of the synaptomenal complex allows for the chromosomes to know if they have successfully paired. This complex can be stained by SPC3 as it binds to the lateral elements of the synaptomenal complex. In this practical, immunostaining process allows for it to be confirmed which proteins are associated with the meiotic chromosomes. This immunostaining process

Chromosome pairs line up across the equator of the spindle at metaphase I (5). In anaphase I the chromosomes separate and travel to opposite ends of the spindle. The chromosomes migrate to the equators of two new spindles for metaphase 2 (7). Next the chromatids are pulled apart in anaphase 2 to form four clusters of chromosomes in telophase 2. The nuclear envelopes reform around four haploid nuclei that will give rise gamete

[A labelled diagram of Metaphase here, and put a note next to it saying "Note

These bivalents line up along the equator during metaphase I, the arrangement of the bivalent is completely random and relative to the orientation of the other bivalents, this is known as the independent assortment of chromosomes. This is followed by anaphase I where the homologous chromosomes separate and move to the opposite poles of the cell. At telophase I the cell divides into two, each cell contains one chromosome from each homologous pair. The second stage of meiosis is similar to mitosis.

Mitosis is one of two main methods of cell replication, the other being meiosis. It is “the simple duplication of a cell and all of its parts” resulting from the splitting of a cell. The ‘parent’ or original cell splits, duplicating its DNA (packaged in chromosomes) producing two ‘daughter’ or new cells with the same genetic code. There are four stages of mitosis; Prophase, Metaphase, Anaphase and Telophase. Interphase is not an official phase of mitosis as the cell is at ‘rest’ and not being divided during this phase. It is often called one of the phases of mitosis as it is one of the stages in the life cycle of a cell; however it is not a phase of mitosis due to the fact that no division takes place.