Science Class- Feb 23-27

This week, we learned about heredity.  We started out doing some simulations about peas on the computer.  From the simulations, I learned that if the parents don't have a certain gene, the child won't have it.  Also, if a pea has one capital (dominant) gene and one lowercase (recessive) gene (out of two genes), the pea will display the dominant gene, but will still carry the recessive gene.  One simulation talked about Gregor Mendel, a Swiss monk who studied peas and how they passed down traits.  

As we went through and discussed the simulations as a class, I developed some more hypotheses.  They are:

1. capital letters are dominant genes; lowercase are recessive

2. the gene is always displayed if there are two of them- upper or lowercase

3. if there is one of each gene, each gene has an equal chance of being passed down, but the dominant gene is displayed

4. if neither parent has a certain gene, the children will not have it

5. if both parents total four of the same gene, all of the children will have two of the gene

After we learned more about the genes, we made Punnet Squares.  They use the homologous pairs, which are the two same letters (Yy, TT, rr, ect), of the parents to find out the possible homologous pairs for the children.  

When we got the hang of this, we learned some new vocabulary:

dominant- visible gene

recessive- hidden gene

heterozygous- different genes (Yy)

homozygous- same genes (YY,yy)

homozygous dominant- homo with dominant genes (YY)

homozygous recessive- homo with recessive genes (yy)

allele- alternate form of a gene (y,G,B,D,f,c)

genotype- description of the allele combination (genetic code) ex. Yy (for yellow color)

phenotype- individual's appearance (physical qualities) ex. yellow