sex reversal
Quick Summary
Sex reversal in biology refers to instances where an individual's genetic sex does not align with their phenotypic sex. This can occur due to abnormal chromosome effects, such as variations in the number of sex chromosomes (X and Y). For example, individuals with XXY chromosomes may appear male but have underdeveloped testes, while XO individuals are phenotypically female but remain immature.12
In some species, like certain nematodes, sex reversal can be influenced by environmental conditions or population sex ratios, leading to intersex individuals with characteristics of both sexes. In other cases, such as in some insects, genetic abnormalities can result in "sexual mosaics" where different parts of the body exhibit male and female characteristics. The underlying mechanisms involve the complex interplay of chromosomes and genes, particularly those located on sex chromosomes, which dictate the development of primary and secondary sexual characteristics.3142
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- reproductive behaviourMollusks
ā¦the young are males; their subsequent sex, however, is determined by their nearest neighbour. They remain males as long as they are near a female but change into females if isolated or placed near another male.
Read Moreā¦the young are males; their subsequent sex, however, is determined by their nearest neighbour. They remain males as long as they are near a female but change into females if isolated or placed near another male.
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gastropodReproduction and life cyclesā¦functional males but, after a transitional phase, spend their remaining life span as females. Crepidula species, for example, form stacks of as many as 19 individuals. The younger ones on top are male, the old ones on the bottom female, and those in the middle are intermediate in sex. Isolatedā¦
Read Moreā¦functional males but, after a transitional phase, spend their remaining life span as females. Crepidula species, for example, form stacks of as many as 19 individuals. The younger ones on top are male, the old ones on the bottom female, and those in the middle are intermediate in sex. Isolatedā¦
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