Presentation on theme: "Vocabulary for Punnett Squares In describing the inheritance of genes, some additional terms are useful."— Presentation transcript:
Vocabulary for Punnett Squares In describing the inheritance of genes, some additional terms are useful.
Phenotype An organisms Phenotype is the physical appearance of a trait. For example, in the Class Traits activity, there were two possible phenotypes for hair line-widows peak or no widows peak. For Mendels peas, the phenotypes for seed shape were round or wrinkled.
What are the two possible phenotypes for earlobe style?
Allele form of a trait P or p inside Easter egg halves
Genotype Genotype is the organisms allele combinations, or gene type. There are three possible genotypes for chin shape CC, Cc, or cc.
Three additional terms can be used to describe a genotype: homozygous dominant = both genes are dominant (ex: WW); called Purebreds by Mendel. homozygous recessive = both genes are recessive (ex: ww); called Purebreds by Mendel. heterozygous = one dominant and one recessive gene (ex: Ww); called Hybrids by Mendel.
Hard Science Words By now, youve probably begun to recognize that many hard science words are made up of prefixes, roots, and suffixes, and if the word is broken down, the meaning is easier to remember.
For Example In the words heterozygous and homozygous the prefix hetero means different; and the prefix homo means same. So, heterozygous means there are two different alleles; homozygous means there are two of the same alleles (either two dominant or two recessive).