4°00N 73°28E, pop (2000e) 76 000; area 2 km²/0·77 sq mi. Chief atoll and capital of the Maldives; over 700 km/435 mi WSW of Sri Lanka; airport; commercial centre; trade in breadfruit, copra, palm mats.
In heterogamous species, male is the sex of an organism, or of a part of an organism, which typically produces smaller, mobile gametes (spermatozoa) that are able to fertilise female gametes (ova). Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. In land plants, female and male designate not only the female and male gamete-producing organisms and structures, but also the structures of the sporophytes that give rise to male and female plants.
Secondary sex characteristics
In those species with separate sexes, males may differ from females in ways other than production of spermatozoa. Males are generally smaller than females in seed plants (the pollen grain is the male plant) and many fishes and birds, but larger in many mammals, including humans.
Sex determination
The sex of a particular organism may be determined by a number of factors. Although most species with male and female sexes have individuals that are either male or female, hermaphroditic animals have both male and female reproductive organs.
Genetic determination
Most mammals, including humans, are genetically determined as such by the XY sex-determination system where males have an XY (as opposed to XX) sex chromosome. During reproduction, a male can give either an X sperm or a Y sperm, while a female can only give an X egg. The ZW sex-determination system, where males have a ZZ (as opposed to ZW) sex chromosome may be found in birds and some insects and other organisms. Members of Hymenoptera, such as ants and bees, are determined by haplodiploidy, where most males are haploid and females and some sterile males are diploid. Other species, such as some snails, practice sex change: adults start out male, then become female.
Anatomy
All males, regardless of independent origin, kingdom, or other phylogenetic subdivision, share at least the anatomy to produce male gametes.
Even where structures and cell types have arisen independently, "sperm" is ordinarily used to refer to the male gamete.
Symbols
A common symbol used to represent the male gender is the Mars symbol, ♂ (Unicode: U+2642 Alt codes: Alt+11)—a circle with an arrow pointing northeast.
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