Sexual Reproduction is a process that creates a new organism by combining the genetic material of two organisms; it occurs both in eukaryotes and in prokaryotes. A key similarity between bacterial sex and eukaryotic sex is that DNA originating from two different individuals (parents) join up so that homologous sequences are aligned with each other, and this is followed by exchange of genetic information (a process called genetic recombination). After the new recombinant chromosome is formed it is passed on to progeny.
Asexual Reproduction It can be advantageous and/or disadvantageous. One positive aspect is that it can create individuals rapidly and in large quantities. Secondly, bypassing the sexual process can help a plant in times of dryness since motile sperm require water to fertilize the egg. Another advantage lies in the fact that plants with the desired characteristics can be cloned for economic reasons (agriculture). However, if something goes wrong, such as the occurrence of a fatal mutation, the whole society of clones can be terminated. For this reason, farmers are careful in determining how to propagate their vegetation. In conclusion, the asexual process of reproduction is an important one to plants.
Mitosis Is the process by which a cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is a form of karyokinesis, or nuclear division. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles, and cell membrane into two cells containing roughly equal shares of these cellular components.[1] Mitosis and cytokinesis together define the mitotic phase of the cell cycle—the division of the mother cell into two daughter cells, genetically identical to each other and to their parent cell. This accounts for approximately 10% of the cell cycle.
Meiosis The meiosis has many parts like: Diploid Cell: From a preceding mitotic division, the ogonium (Spermatogonium) enters meiosis with DIPLOID chromosomes but TETRAPLOID DNA. Chromosomes then duplicate to produce SISTER CHROMATIDS (or HOMOLOGOUS DYADS). Prophase I: Dyad pairs align to create "TETRADS", non-sister chromatids connect and trade sections at a "CHIASMA", a process called "CROSSING OVER". Metaphase I: SPINDLE FIBERS attach to each dyad at the KINETOCHORE. Tension from spindle fibers aligns the tetrads at the cell equator. Anaphase I: Chiasmata break apart and sister chromatids begin migrating toward opposite poles.
Telophase I: CLEAVAGE FURROW forms beginning the process of CYTOKINESIS (cell division). Resulting daughter cells are HAPLOID. Prophase II: Spindle formation begins and centrosomes begin moving toward poles. Metaphase II: Tension from spindle fibers aligns chromosomes at the metaphase plate. Anaphase II: CHROMATIDS separate and begin moving to the poles. Telophase II: CLEAVAGE FURROW forms beginning CYTOKINESIS. Gamete: NUCLEAR ENVELOPES form and chromosomes disperse as CHROMATIN. Meiosis has produced 4 DAUGHTER CELLS, each with 1N chromosomes and 1N DNA. Later, in fertilization, male and female 1N gametes will fuse to form a 2N ZYGOTE.
Allogamy Is a term used in the field of biological reproduction describing the fertilization of an ovum from one individual with the spermatozoa of another. By contrast, autogamy is the term used for self-fertilization. In humans, the fertilization event is an instance of allogamy. Self-fertilization (also known as autogamy) occurs in hermaphroditic organisms where the two gametes fused in fertilization come from the same individual.
Autogamy Of male and female gametes (sex cells) produced by the same individual. Selffertilization occurs in bisexual organisms, including most flowering plants, numerous protozoans, and many invertebrates. Autogamy, the production of gametes by the division of a single parent cell, is frequently found in unicellular organisms such as the protozoan Paramecium.
Image of Asexual Reproduction:
Image of Mitosis:
Image of Meiosis:
Image of Autogamy: