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==Key Stage 3==
===Meaning===
[[ChromosomesChromosome]] s are coils of [[DNA]] found in the [[Cell Nucleus|nucleus]].
{| class="wikitable"
: Humans have 46 chromosomes.
: Chromosomes come in pairs, one from the father and one from the mother.
: 23 [[chromosome]]s are from the father and 23 [[chromosome]]s are from the mother.
: The last 2 chromosomes are called sex chromosomes and they determine if the [[offspring]] is [[male]] or [[female]]. If the human has two [[X Chromosome]]s then they are [[female]]. If the human has an X and a [[Y Chromosome]] they are [[male]].
==Key Stage 4==
===Meaning===
A [[chromosome]] is a section of [[DNA]] that has coiled together.
===About Chromosomes===
: [[Chromosome]]s are found in pairs in [[diploid]] [[Cell (Biology)|cells]].
: In [[organism]]s which engage in [[Sexual Reproduction|sexual reproduction]] one of the [[chromosome]]s in the pair is [[Heredity|inherited]] from the mother and the other from the [[father]].
: During [[mitosis]] [[chromosome]]s have made copies of themselves that are joined by a [[centromere]].
: In [[haploid]] [[Cell (Biology)|cells]] there are half the [[number]] of [[chromosome]]s. These [[Cell (Biology)|cells]] are [[gamete]]s used in [[Sexual Reproduction|sexual reproduction]].
===About Human Chromosomes===
: Humans have 46 chromosomes.
: 23 [[chromosome]]s are from the father and 23 [[chromosome]]s are from the mother.
: The last 2 chromosomes are called sex chromosomes and they determine if the [[offspring]] is [[male]] or [[female]]. If the human has two [[X Chromosome]]s then they are [[female]]. If the human has an X and a [[Y Chromosome]] they are [[male]].