FC: Mitosis and Meiosis by Jessy Acfalle
1: Mitosis vs Meiosis by Jessy Acfalle
2: Interphase | Interphase is divided into 3 stages; G1, S, and G2 stage. During G1 or the "growth" stage the cell doubles or grows in size, along with its organelles needed to carry out specialized functions. The cell is preparing itself for DNA replication. | During the S stage of interphase, the cell copies or duplicates its DNA preparing for cell division. Chromosomes are structures that contains all the cells genetic material, and the relaxed form of DNA is chromatin.The genetic material or DNA is passed from generation to generation of the cell.
3: The final stage of interphase is the G2 stage. In this stage the cell prepares for the division of its nucleus. A protein that produces microtubules for cell division is synthesized at this time. Spindle fibers also start to form during the S stage, and the cell takes inventory and insures the cell is ready for mitosis. | Interphase continued. | Parts of the cell included during this phase: Chromosomes, Nucleus, and Spindle fibers.
4: Prophase | During Prophase the chromatin condenses to form chromosomes. The chromosomes contain replicated DNA that was produced during Interphase,and are formed in an "x" shape. Each half of these "X" figures are called Sister Chromatids, and contain identical copies of DNA. | DIagram 1
5: The Sister Chromatids are connected at the Centromere.(reference to diagram 1) This structure is important because it ensures a complete copy of the DNA will become part of the daughter cells at the end of mitosis. | The Nucleolus disappears and the Nuclear membrane disintegrates, and microtubule structures called spindle fibers form in the cytoplasm. Microtubule structures called centrioles migrate towards the end of the polls. This enitre structure is called the Spindle appratus, and is a key component in organizing the chromosomes before cell division.
6: Sister chromatids are pulled by proteins along the spindle fiber to the equator of the cell. This is the shortest phase of mitosis, but if successfully done it ensures that the cells have accurate replicas of the chromosome. | Metaphase
7: The spindle fiber connects to the centromere when the sister chromatids reach the equator of the cell. (as shown in the figure below)
8: Anaphase | During Anaphase the chromatids are pulled apart, and the spindle fiber starts to shorten towards the centrioles. This causes the centromere of the sister chromatids to break apart into two identical chromosomes. At the end of this stage, proteins help move the chromosomes towards the poles of the cells.
10: Telophase | During Telophase the chromosomes begin to uncoil to chromatin and assemble in pairs at the two poles of the cell. The nuclear membrane starts to reform around the chromosomes, and the spindle fibers disappear.
11: During late telophase the centrioles(microtubule organizing centers) are dispersed to each daughter cell with the replicated DNA .
12: Cytokinesis | The process of cytokinesis is when the cytoplasm of the cell divides along with the plasma membrane and nucleus. Two new daughter cells form from this dividing, with its own nucleus, cytoplasm, and plasma membrane.
14: Meiosis | Cells undergo two rounds during meiosis, to form four new daughter cells. During this process sex cells or gametes are produced. They have half the number of chromosomes (haploid).
16: Mitosis vs. Meiosis | In mitosis cells go through one round of division to produce two identical daughter cells with a full set of chromosomes. (46) During meiosis the cell goes through two rounds of division to form four new daughter cells, with half the number of chromosomes. (23) The cells created during meiosis are sex cells or gametes, and are haploids because they contain half the number of chromosomes.
17: The cells formed during mitosis are body cells and are called diploids because they contain a full set of chromosomes. (46) The number of chromosomes in the beginning of meiosis contain a full set, but decrease to half the number. While during mitosis the chromosome number from the beginning remains the same throughout the whole division process.