See Table 2. Many species of algae have complex life histories and can reproduce through both sexual and asexual means. It is common for algae to have an alternation of generation, where one generation is made through mitotic cell division and the other is made from cells created through meiotic cell division. This document may be freely reproduced and distributed for non-profit educational purposes. Skip to main content. Search form Search. Join The Community Request new password.
Main menu About this Site Table of Contents. Growth, Development, and Reproduction. NGSS Performance Expectations: MS-LS Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation. The content and activities in this topic will work towards building an understanding of how aquatic plants and algae grow, develop, and reproduce. Chromosomes are duplicated.
Meiosis begins in a fashion similar to mitosis with chromosome replication. Matched sets of chromosomes pair together. If you have ever observed a drop of pond water under a microscope, you may have seen a menagerie of squiggly single-celled plants and animals.
Eukaryotic micro-organisms typically reproduce asexually, meaning single cells duplicate their own chromosomal DNA and then divide into two identical cells to maintain the population. Mitosis enables primary food chain producers like diatoms to multiply quickly and abundantly. Complex multicellular organisms with specialized sex cells reproduce sexually, which involves gamete formation and recombining genes through meiosis to achieve biodiversity within the species. After mitosis, the parent cell ends up being one of two identical daughter cells.
Next, the two daughter cells continue to grow and replicate their innards, in preparation for another cell cycle. Interphase is the stage in the cell cycle that precedes the mitotic phases. The nucleus, nucleoli and nuclear membrane remain intact. Organelles make energy for cell growth, and genetic material is duplicated producing homologous identical chromatid pairs connected by a centromere in the middle.
No division is occurring. In prophase , the identical sister chromatids — made of DNA and protein — become visible in the nucleus and look like an X under a microscope.
Protein strands called microtubules start forming; they'll soon capture the chromatids and pull them apart. Binary Fission vs. Mitosis: Key Takeaways Binary fission and mitosis are both forms of asexual reproduction in which a parent cell divides to form two identical daughter cells. Binary fission occurs primarily in prokaryotes bacteria , while mitosis only occurs in eukaryotes e. Binary fission is a simpler and faster process than mitosis. The third main form of cell division is meiosis.
Meiosis only occurs in sex cells gamete formation and produces daughter cells with half of the chromosomes of the parent cell. Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Daughter Cells in Mitosis and Meiosis. Bacterial Reproduction and Binary Fission. A Genetics Definition of Homologous Chromosomes.
What Are Prokaryotic Cells? Structure, Function, and Definition. Centromere and Chromosome Segregation. Frequently Asked Biology Questions and Answers.
Differences Between Bacteria and Viruses. Learn About Amoeba Anatomy and Reproduction. Your Privacy Rights. To change or withdraw your consent choices for ThoughtCo.
At any time, you can update your settings through the "EU Privacy" link at the bottom of any page. These choices will be signaled globally to our partners and will not affect browsing data. We and our partners process data to: Actively scan device characteristics for identification. I Accept Show Purposes. In multiple fission right , a multinucleated cell can divide to form more than one daughter cell.
Multiple fission is more often observed among protists. Starfish reproduce by fragmentation and yeasts reproduce by budding. Both are types of asexual reproduction. Asexual reproduction can be very rapid. This is an advantage for many organisms. It allows them to crowd out other organisms that reproduce more slowly. Bacteria, for example, may divide several times per hour.
Under ideal conditions, bacteria can divide to produce millions of bacterial cells in just a few hours! However, most bacteria do not live under ideal conditions. If they did, the entire surface of the planet would soon be covered with them.
Instead, their reproduction is kept in check by limited resources, predators, and their own wastes. This is true of most other organisms as well. Sexual reproduction involves two parents. As you can see from Figure below , in sexual reproduction, parents produce reproductive cells—called gametes —that unite to form an offspring. Gametes are haploid cells. This means they contain only half the number ofchromosomes found in other cells of the organism. Gametes are produced by a type of cell division called meiosis , which is described in detail in a subsequent concept.
The process in which two gametes unite is called fertilization.
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