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Bahasa Indonesia: Gambaran skematik organ reproduksi wanita, tampak depan. Bahasa Melayu : Lukisan skema organ-organ pembiakan wanita, pandangan depan. Brezhoneg : Brastres eus organoù gouennañ ar merc'hed, gwel a-dal.
The uterus provides mechanical protection, nutritional support, and waste removal for the developing embryo (weeks 1 to 8) and fetus (from week 9 until the delivery). In addition, contractions in the muscular wall of the uterus are important in pushing out the fetus at the time of birth.
Most male fish have two testes of similar size. In the case of sharks, the testes on the right side is usually larger [citation needed].The primitive jawless fish have only a single testis, located in the midline of the body, although even this forms from the fusion of paired structures in the embryo.
Near et al. (2012) explored the phylogeny and divergence times of every major lineage, analysing the DNA sequences of 9 unlinked genes in 232 species. They obtained well-resolved phylogenies with strong support for the nodes (so, the pattern of branching shown is likely to be correct).
The first fossilized evidence of sexual reproduction in eukaryotes is from the Stenian period, about 1.05 billion years old. [19] [20]Biologists studying evolution propose several explanations for the development of sexual reproduction and its maintenance.
A tuna (pl.: tunas or tuna) is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae family.The Thunnini comprise 15 species across five genera, [2] the sizes of which vary greatly, ranging from the bullet tuna (max length: 50 cm or 1.6 ft, weight: 1.8 kg or 4 lb) up to the Atlantic bluefin tuna (max length: 4.6 m or 15 ft, weight: 684 kg or 1,508 lb [citation ...
Reconstruction of Cephalaspis lyellii. Cephalaspidomorphs were, like most contemporary fishes, very well armored. The head shield was particularly well developed, protecting the head, gills and the anterior section of the viscera.
Various groups of placoderms were diverse and abundant during the Devonian, but all placoderms became extinct at the end-Devonian Hangenberg event 358.9 million years ago, [7] leaving the niches open for the osteichthyan and chondrichthyan survivors who subsequently radiated during the Carboniferous.