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Male: average 15–30 centimetres (5.9–11.8 in); more slender than the female; Female: average 20–35 centimetres (7.9–13.8 in) The body is long, cylindrical, and fusiform (pointed at both the ends). The body wall is composed of cuticle, epidermis and musculature. There is a pseudocoelom.
Fertile egg as can be seen in a microscope Fertile egg in human faeces (detail) Infertile egg. Ascaris lumbricoides is characterized by its great size. Males are 2–4 mm (0.08–0.2 in) in diameter and 15–31 cm (5.9–12 in) long. The male's posterior end is curved ventrally and has a bluntly pointed tail.
The female insect's main reproductive function is to produce eggs, including the egg's protective coating, and to store the male spermatozoa until egg fertilisation is ready. The female reproductive organs include paired ovaries which empty their eggs (oocytes) via the calyces into lateral oviducts, joining to form the common oviduct.
The males of many species of Papilionoidea are furnished with secondary sexual characteristics. These consist of scent-producing organs, brushes, and brands or pouches of specialised scales. These presumably meet the function of convincing the female that she is mating with a male of the correct species. [11]
Sperm competition occurs when a female is inseminated by multiple males during one breeding season resulting in differential fertilization success among males. In birds, the last male to inseminate the female usually fertilizes the highest proportion of eggs because by the time fertilization occurs, the oldest spermatozoa have been lost. [42]
Male genitalia of Lepidoptera. The main component of the male reproductive system is the testicle, suspended in the body cavity by tracheae and the fat body.The more primitive apterygote insects have a single testis, and in some lepidopterans the two maturing testes are secondarily fused into one structure during the later stages of larval development, although the ducts leading from them ...
Cloacal kiss, which consists in that the two animals touch their cloacae together in order to transfer the sperm of the male to the female. It is used in most birds and in the tuatara, that do not have an intromittent organ. [6] Via spermatophore, a sperm-containing cap placed by the male in the female's cloaca. Usually, the sperm is stored in ...
Oviparity: internal fertilisation, where the female lays zygotes as eggs with important vitellus (typically birds) Ovoviviparity can be thought of as a form of oviparity where the zygotes are retained in the female's body or in the male's body, but there are no trophic interactions between zygote and parents. This is found in Anguis fragilis.