FOSS notes Heredity
 Heredity is the passing of information from one generation to the next.
 Chromosomes are structures that contain hereditary info and transfer it to
the next generation; they occur in nearly identical pairs in the nucleus of
every cell.
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Nuclei contain chromosomes.
Chromosomes come in almost identical pairs
Chromosomes have specific active locations called alleles.
The two alleles in identical locations on paired chromosomes make up a gene.
 Genes are the basic units of heredity carried by chromosomes. Genes code
for features of organisms.
 Alleles are variations of genes that determine traits; the two alleles on
paired chromosomes make up a gene.
 Alleles can be dominant or recessive. Dominant alleles are expressed if
they are present on one chromosome; recessive alleles are expressed
only when both chromosomes have the allele.
 An organism’s particular combination of paired alleles is its genotype; the
traits produced by those alleles result in the organism’s phenotype.