The Importance of Reproductive SuccessAn organism that has offspring that is fertile is reproductively successful. Reproductive success is mandatory to keep a species alive and going.
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Asexual vs. Sexual ReproductionAsexual reproduction is a form of reproduction that requires only one parent and makes identical clones of the parent.Examples of asexual reproduction include binary fission, performed in bacteria, vegetative propagation, performed in plants such as strawberries, and fragmentation, performed in sea stars and sponges. Sexual reproduction involves two parents, the joining of gametes, and results in genetically variable offspring. This from of reproduction is performed by complex animals such as humans. Below is a chart demonstrating how offspring from sexual reproduction or genetically variable, whereas in asexual reproduction they are identical.
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Mitosis vs. Meiosis
Mitosis is the process of cell division in which a cells divides into two identical daughter cells. These cells are diploid cells, meaning they have a full set of chromosomes. The purpose of mitosis is general growth and repair for the body, such as the production of skin cells. Mitosis occurs in all organisms. Meiosis is the process of cell division resulting in four gametes, or sex cells. These gametes are all haploid cells, meaning they have a half set of chromosomes. The purpose of meiosis is to produce gametes, which may be used in fertilization. Meiosis does not occur in all organisms; it occurs in humans, animals, etc. Both mitosis and meiosis include the steps interphase, prophase, metaphase, anaphase, and telophase. Interphase is the longest step, in which the cell grows and DNA replicates. In prophase, the nucleus dissolves, chromosomes become visible, and centrioles separate to forming the spindle fibers. During metaphase, the replicated chromosomes line up in the middle of the cell and the spindle fibers attach to the centromeres that attach the chromatids together. During anaphase, the chromatids pull apart. In telophase, two cells pinch off and form. This is the end in mitosis, but meiosis repeats a second time (prophase II, metaphase II, anaphase II. and telophase II), resulting in four cells.
How Does the Nine Banded Armadillo Reproduce?
"Mating takes place during a two- to three-month-long mating season, which occurs from July–August in the Northern Hemisphere and November–January in the Southern Hemisphere." [1]. An armadillo's reproductive process is extremely unique and different. After a single egg is fertilized an armadillo is able to delay implantation to the uterus for up to four months to ensure it is born at a good time. After the egg is implanted, it goes through a four month gestation period. During these four months, eggs splits into four identical embryos, each having its own placenta. Therefore, armadillos always give birth to four identical young. They reproduce every year for their lifespan (12-15 years). There rapid reproduction is what helps keeps the armadillo species alive and expanded.