Cell Division Meiosis Flashcards
is a specialized cell division process that occurs in sexually reproducing organisms, forming haploid gametes (sperm and egg cells) from diploid parent cells.
Meiosis
Chromosome Condensation:
Chromatin condenses into visible chromosomes, sach consisting of two sister chromatids.
Homologous Chromosome Pairing:
Marked by the pairing of homologous chromosomes through a process called synapsis.
Nudear Envelope Breakdown and Formation of Spindle Fiber.
The nudear envelope begins to break down; allowing the attachment of the spindle fiber formed.
Prophase 1
A process during Prophase I of meiosis, where homologous chromosomes exchange genetic material.
This occurs at specific points called chiasmata or chiasma, where the chromatids of homologous chromosomes physically overlap.
During this process.
•Non-sister chromatids break at corresponding points.
•These broken segments are then swapped between the chromatids.
•The exchanged segments reconnect, resulting in new combinations of genes.
Crossing over
Chromosome Alignment:
Paired homologous chromosomes align along the metaphase plate.
Spindle Fiber Aftachment:
Spindle fibers from opposite cell poles attach to the centremeres of the homologous chromosomes.
Metaphase 1
The way the homologous pairs align is independent of how other pairs align. This means each pair’s orientation is random, allowing different combinations of maternal and paternal chromosomes to be passed on to the daughter cells:
Independent assortment
Homologous Chromosome Separation:
_____is marked by the separation of homologous chromosome pairs. Each member of the homologous pair is pulled toward opposite poles of the cell.
Reduction in Chromosome Number:
The chromosome number is halved. This reduction is a key feature of meiosis.
Anaphase 1
Nuclear Envelopes Reform:
Nudear envelopes start to reassemble around the separated sets of chromosomes at the opposite poles of the cell.
2 nuclei are formed each containing half of the starting number of chromosomes.
Telophase 1
2 haploid cells are formed
The 2 cells are genetically different
Cytokinesis1
Sister Chromatid Separation:
Meiosis___is characterized by the separation of sister chromatids.
Four Haploid Daughter Cells:
Meiosis It concludes with the formation of four haploid daughter cells, each containing a unique combination of genetic material.
Meiosis 2
Sister Chromatid Separation:
Meiosis____is characterized by the separation of sister chromatids.
Four Haploid Daughter Cells:
Meiosis It concludes with the formation of four haploid daughter cells, each containing a unique combination of genetic material.
Meiosis 2
Chromosome Condensation:
The chromosomes condense once again as the nuclear envelope breaks down.
Formation of Spindle Fibers:
The spindle apparatus re-forms in prophase II.
Prophase 2
Chromosome Alignment:
Individual chromosomes align along the
metaphase plate.
Spindle Fiber Attachment:
Spindle fibers attach to the contromeres of individual chromosomes in metaphase II.
Haploid Cell Formation:
Gore bulaicgy ufult ensures that
It ensures that the resulting daughter cells will be haploid, containing half the original chromosome number
Metaphase 2
Sister Chromatid Separation: ___of meiosis involves the separation of sister chromatids, which were held together by centromeres in metaphase Il.
Chromatids are pulled towards
opposite poles of the cell.
Anaphase 2
Resulting in Four Haploid Daughter Cells:
In meiosis Il,____occurs after the separation of sister chromatids. As a result, each initial haploid cell undergoing meiosis Il divides into two, yielding a total of four haploid daughter cells, each with a unique combination of genetic material.
Cytokines 2
is the process by which germ cells undergo meiosis to form haploid gametes (sperm and eggs)
Gametogenesis
