Search results
Results from the WOW.Com Content Network
Human reproduction usually involves internal fertilization by sexual intercourse. In this process, the male inserts his penis into the female's vagina and ejaculates semen, which contains sperm. A small proportion of the sperm pass through the cervix into the uterus and then into the fallopian tubes for fertilization of the ovum. Only one sperm ...
A cladistic analysis based on modern discoveries about the biology of these organisms supports a relatively close relationship with some photosynthetic organisms, such as brown algae and diatoms. A common taxonomic classification based on these data, places the class Oomycota along with other classes such as Phaeophyceae (brown algae) within ...
Pheretima is a genus of earthworms found mostly in New Guinea and parts of Southeast Asia.. Species belonging to the genus Pheretima have a clitellum, which is a band of glandular tissue present on segments 14 to 16.
[10] Oogenesis in eukaryotic cells. (A) oogonium where the mitotic division occurs (B) differentiation and meiosis I begins (C) primary oocyte (D) meiosis I is completed and meiosis II begins (E) secondary oocyte (F) first polar body (G) ovulation must occur and the presence of the sperm penetration (fertilization) induces meiosis II to ...
Sexual reproduction is the most common life cycle in multicellular eukaryotes, such as animals, fungi and plants. [6] [7] Sexual reproduction also occurs in some unicellular eukaryotes. [2] [8] Sexual reproduction does not occur in prokaryotes, unicellular organisms without cell nuclei, such as bacteria and archaea.
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.
Isogamy is a form of sexual reproduction that involves gametes of the same morphology (indistinguishable in shape and size), and is found in most unicellular eukaryotes. [1] Because both gametes look alike, they generally cannot be classified as male or female . [ 2 ]
An online system named ePathshala, a joint initiative of NCERT and Ministry of Human Resource Development, has been developed for broadcasting educational e-schooling resources including textbooks, audio, video, publications, and a variety of other print and non-print elements, [18] ensuring their free access through mobile phones and tablets ...