Word bank: phenotype, genotype, heterozygous, homozygous, traits,
alleles, genes

Chromosomes contain , which help to determine an
organism’s . Genes come in alternate forms called
, and both parents may not have the same type of
allele. The actual gene combination that an organism
receives from its parents is called its , while the trait
that gets expressed as a result is referred to as its . If
an offspring receives the same type of allele for a given
gene from each parent, it is said to be for that trait.
If the alleles differ, it is .