meiosis

• What does meiosis produce?


  4 genitally different daughter cells
• what is meiosis used to produce int he body(what type of cell)


  gametes
• how many cell divisions are their in meiosis


  2
• what happens in the first stage of meiosis(meiosis 1)


  the chromosome number is halved
• What happens in Meiosis II?


  the new haploid cells divide again
• What is a bivalent?


  a pair of homologous chromosomes
• what happens at the start of prophase 1 in meiosis 1


  the chromosomes condense and become visible as two sister chromatids joined at the centromere
• when is a bivalent formed


  formed during prophase of meiosis I when the 2 homologous chromosomes in a pair come together.
• in prophase 1 what happens after the homologous chromosomes pair up in a bivalent


  the chromatids wrap around each other and then partially repel each other but remain joined at points called the chiasmata
• what happens in prophase 1 after the chromatids are joined together at points


  the homologous chromosomes can exchange equivalent sections of DNA
• what is the swapping of DNA between chromosomes called in prophase 1 of meiosis 1


  crossing over
• after the homologous chromosomes swapped some DNA what happens in prophase 1


  the nuclear envelope disintegrates , the nucleolus disappears and the centrioles move to opposite poles
• what is the first stage of metaphase 1


  the microtubules of spindles attach to centromeres
• what is meant by independent assortment


  this is when pairs of homologous chromosomes align randomly along the spindle at the equator
• what does metaphase one result in


  the random combination of paternal and maternal chromosomes in each daughter cell
• what is the first stage of anaphase 1


  spindle fibres contract and shorten ,bivalents separates and chromosomes are pulled to opposite sides
• in anaphase what is received at each end pole


  one of each homologous pair of chromosomes
• in meiosis 1 what can happen in telophase 1


  the nuclear envelope can reform or the chromosomes can stay in their condensed form
• in telophase 1 what will happens if the nuclear envelope reforms


  the nuclear envelope will form around the haploid group of chromosomes and the chromosomes will unwind
• what is the final stage of meiosis


  cytokinesis
• what is cytokinesis


  division of the cytoplasm
• what is formed from cytokinesis


  2 haploid cells