Search results
Results from the WOW.Com Content Network
Chlamydomonas (/ ˌ k l æ m ɪ ˈ d ɒ m ə n ə s,-d ə ˈ m oʊ-/ KLAM-ih-DOM-ə-nəs, -də-MOH-) is a genus of green algae consisting of about 150 species [2] of unicellular flagellates, found in stagnant water and on damp soil, in freshwater, seawater, and even in snow as "snow algae". [3]
In both organisms after pheromone exchange, cells grow in a polarized manner in the direction of their partner and undergo fusion, karyogamy and sporulation. The role of karyogamy in sexual reproduction can be demonstrated most simply by single-celled haploid organisms such as the algae of genus Chlamydomonas or the yeast Saccharomyces ...
Asexual reproduction occurs when the cell protoplast divides to form two, four, or eight daughter cells, with cell walls forming while still in the parent cell wall. Before cell division, the flagella usually disappear. Daughter cells are typically liberated when the parent cell wall gelatinizes, or through a rupture in the parent cell wall.
The zygote is the earliest developmental stage. In humans and most other anisogamous organisms, a zygote is formed when an egg cell and sperm cell come together to create a new unique organism. The formation of a totipotent zygote with the potential to produce a whole organism depends on epigenetic reprogramming.
Chlamydomonas moewusii is a heterothallic species, exhibiting distinct behavioral differences between the gametes of its two mating types. When suspensions containing 'plus' and 'minus' gametes are mixed under light, they form clumps that eventually separate into pairs after a few minutes.
Chlamydomonas reinhardtii is a single-cell green alga about 10 micrometres in diameter that swims with two flagella. It has a cell wall made of hydroxyproline -rich glycoproteins , a large cup-shaped chloroplast , a large pyrenoid , and an eyespot apparatus that senses light.
Another theory is that sexual reproduction originated from selfish parasitic genetic elements that exchange genetic material (that is: copies of their own genome) for their transmission and propagation. In some organisms, sexual reproduction has been shown to enhance the spread of parasitic genetic elements (e.g. yeast, filamentous fungi). [80]
Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. There are two forms of reproduction: asexual and sexual. In asexual reproduction, an organism can reproduce without the involvement of another organism.