What is Reproduction?
Reproduction, which can be done sexually or asexually, is important for the survival of a species. Sexual reproduction is when organisms are produced from two organisms or two parents. Also in sexual reproduction, there are two sexes, so two different types of organisms are needed. With sexual reproduction, no two offspring will be exactly the same. It is a combination of traits and chromosomes resulting in varied organisms. Asexual reproduction however, creates identical organisms. Asexual reproduction is found in bacteria, plants, sponges, starfish, etc. In asexual reproduction there a is replication of DNA from parent to offspring. There four types of asexual reproduction: vegetative propagation, budding, fragmentation, and binary fission. Offspring in asexual reproduction come from a single parent, only receiving genes and traits from that one parent, therefore leading to identical offspring.
Mitosis vs Meiosis
Mitosis is the process in which a cell duplicates into two genetically identical cells. This process is done in the cell cycle for asexual reproduction. The phases if mitosis are interphase, prophase, metaphase, anaphase, and telophase. Through these phases mitosis copies all of the genetic material of a diploid cell (46 chromosomes) and makes another one. In interphase what happens is where the cell is in its non-divding stage, and where you can see chromatin. In prophase is when the chromosomes appear, the nucleus dissolves, and where the spindle fibers form. In metaphase the chromosomes line up in the middle. During anaphase, the sister chromatids divide. Finally in telophase, the two cells form.
Meiosis is similar to mitosis, but serves a different purpose. Meiosis is cell division that results in 4 haploid cells. This process is done in the cell cycle for sexual reproduction. Haploid cells are gametes or sex cells, such as the sperm or egg. Haploid cells have 23 chromosomes. Meiosis has the same phases as mitosis, only difference being it results in 4 cells. Meiosis in woman takes places in the ovaries, and in the men takes place in the testes. With women it happen before birth and every month during their menstrual cycle. With men it happens during puberty. The result of meiosis is variety is variety in genes when sexual reproduction takes place.
Mitosis vs Meiosis
Mitosis is the process in which a cell duplicates into two genetically identical cells. This process is done in the cell cycle for asexual reproduction. The phases if mitosis are interphase, prophase, metaphase, anaphase, and telophase. Through these phases mitosis copies all of the genetic material of a diploid cell (46 chromosomes) and makes another one. In interphase what happens is where the cell is in its non-divding stage, and where you can see chromatin. In prophase is when the chromosomes appear, the nucleus dissolves, and where the spindle fibers form. In metaphase the chromosomes line up in the middle. During anaphase, the sister chromatids divide. Finally in telophase, the two cells form.
Meiosis is similar to mitosis, but serves a different purpose. Meiosis is cell division that results in 4 haploid cells. This process is done in the cell cycle for sexual reproduction. Haploid cells are gametes or sex cells, such as the sperm or egg. Haploid cells have 23 chromosomes. Meiosis has the same phases as mitosis, only difference being it results in 4 cells. Meiosis in woman takes places in the ovaries, and in the men takes place in the testes. With women it happen before birth and every month during their menstrual cycle. With men it happens during puberty. The result of meiosis is variety is variety in genes when sexual reproduction takes place.
Reproduction of Feather Stars
Feather stars have separate sexes; male and female. Their gametes (sperm and egg) are released into the water where they are fertilized. (7) The gametes are released through pinnules, which are seen on their arms. The pinnules carry out and eject the gametes into the water. (8) Once the sperm and egg join, they become small drifting, non-feeding larvae. Then, they transform into a stalked, non-feeding, bottom-dweling larvae who then develop into stalked, bottom dwelling young feather star. Feather stars are able to reproduce once they are twelve to eighteen months. (7)