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Chromosomes and Meiosis: Terminology and Definitions
no Term Terminology / Definition
1 Allele An allele is one of the possible forms of a gene.
Is a variant form of a gene.
Most genes have two alleles, a dominant allele and a recessive
allele.
Are pairs or series of genes on a chromosome that determine the
hereditary characteristics.
An example of an allele is the gene that determines hair colour.
2 Crossing over Crossing over is the process where homologous chromosomes pair up
with each other and exchange different segments of genetic
material to form recombinant chromosomes.
It occurs between prophase 1 and metaphase 1 of meiosis
4 Egg cells (ovules, ovum) The egg cell, or ovum (plural ova), is the female reproductive cell
(gamete) in oogamous organisms.
(Oogamous - relating to or denoting
The egg cell is typically not capable of active movement, and it is
reproduction by the union of mobile
male and immobile female much larger (visible to the naked eye) than the motile sperm cells.
gametes)
Chromosomes and Meiosis: Terminology and Definitions
no Term Terminology / Definition
1 Allele An allele is one of the possible forms of a gene.
Is a variant form of a gene.
Most genes have two alleles, a dominant allele and a recessive
allele.
Are pairs or series of genes on a chromosome that determine the
hereditary characteristics.
An example of an allele is the gene that determines hair colour.
2 Crossing over Crossing over is the process where homologous chromosomes pair up
with each other and exchange different segments of genetic
material to form recombinant chromosomes.
It occurs between prophase 1 and metaphase 1 of meiosis
4 Egg cells (ovules, ovum) The egg cell, or ovum (plural ova), is the female reproductive cell
(gamete) in oogamous organisms.
(Oogamous - relating to or denoting
The egg cell is typically not capable of active movement, and it is
reproduction by the union of mobile
male and immobile female much larger (visible to the naked eye) than the motile sperm cells.
gametes)
