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Garden snails mating. A hermaphrodite (/ h ər ˈ m æ f r ə ˌ d aɪ t /) is a sexually reproducing organism that produces both male and female gametes. [1] Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic.
Gonochorism has evolved independently multiple times. [8] It is very evolutionarily stable in animals. [9] Its stability and advantages have received little attention. [10]: 46 Gonochorism owes its origin to the evolution of anisogamy, [11] but it is unclear if the evolution of anisogamy first led to hermaphroditism or gonochorism.
A penis (/ ˈ p iː n ɪ s /; pl.: penises or penes) is a male sex organ that is used to inseminate female or hermaphrodite animals during copulation. [1] [2] Such organs occur in both vertebrates and invertebrates, including humans, but not in all male animals. The term penis applies to many intromittent organs, but not to all.
In 45% of mammal species, males are larger than females, in 39%, males and females are the same size and in 16% of mammals, females are larger than males. [90] Both genes and hormones affect the formation of many animal brains before " birth " (or hatching ), and also behaviour of adult individuals.
Invertebrates cells fire in response to similar stimuli as mammals, such as tissue trauma, high temperature, or changes in pH. The first invertebrate in which a neuron cell was identified was the medicinal leech, Hirudo medicinalis. [14] [15] Learning and memory using nociceptors in the sea hare, Aplysia has been described.
The symbol of the Roman god Mars (god of war) is often used to represent the male sex. It also stands for the planet Mars and is the alchemical symbol for iron.. Male (symbol: ♂) is the sex of an organism that produces the gamete (sex cell) known as sperm, which fuses with the larger female gamete, [1] [2] [3] or ovum, in the process of fertilisation.
During copulation, one clasper is inserted into the female's cloaca, and sperm is flushed by the male's body through a groove into the female. [7] Members of Poeciliidae are small fishes that give birth to live young. In males, the anal fin is shaped into a grooved, rod-shaped organ called a gonopodium used to deliver sperm to females. [8]
Intersex is a general term for an organism that has sex characteristics that are between male and female. [1] It typically applies to a minority of members of gonochoric animal species such as mammals (as opposed to hermaphroditic species in which the majority of members can have both male and female sex characteristics). [2]