Lab Report: Developmental Biology and Human Molecular Genetics

Your Name:
SECTION ONE: HUMAN MOLECULAR GENETICS
Pre-Lab Questions
1). What do the letters on the outside of a Punnett square represent? What do the letters on the inside of a Punnett square represent?
The letters outside the Punnett square represents each parental genotype one on the rows and one on the column
The letters on the inside of a Punnett square represent represents the predicted frequency of all of the potential genotypes among the offspring each time reproduction occurs.
2). Suppose you live in a population which expresses curly, straight, or wavy hair. Assume this is a monogenic trait. Curly- and straight-haired individuals are homozygous, while wavy-haired individuals are heterozygous. Based on the Introduction information, what pattern of inheritance most likely causes these phenotypes?
Curly and straight hair represents the dominant traits while having wavy hair is the recessive trait.
3). The following equation can be used to determine the total number of possible genotypes for a gamete using any number of heterozygous genes: 
2g = Number of possible genotypes
where “g” is the number of heterozygous genes. For example:
1 gene: 21 = 2 gamete genotypes
2 genes: 22 = 4 gamete genotypes
3 genes: 23 = 8 gamete genotypes
Consider the following genotype: Ee Ff AA. How many different gamete genotypes can be produced from the Ee Ff AA genotype?
1 Gamete genotypes.
4). Phenotypes, such as eye color, are controlled by multiple genes. This type of inheritance is called polygenic. If eye color was controlled by the number of genes indicated below, how many possible genotypes would there be?
1 gene: 21 = 2 gamete genotypes
Thus, the number of genes (g) = 2g
10 Genes: 1024
15 Genes: 32768
1 Genes: 1048576
5). Compare and contrast monogenic disorders and chromosomal disorders.
Monogenic disorders are disorders caused by variation in a single gene and are usually recognized by their striking familial inheritance patterns. A single gene defect commonly does not cause the chromosome structure or number to be abnormal. An individual can have normal genes, but, he or she can also have extra copies of genes due to a chromosome abnormality. The extra copies can cause the genes to malfunction. An individual can possess normal chromosomes in number and structure, but still express a disease, disorder, or condition due to a mutation in one or more of the genes on the chromosomes. A single gene defect usually does not cause the chromosome structure or number to be abnormal.
6). Describe the basic storage mechanism for DNA using the words histone complex, nucleosome, chromatin, and chromosome.
Chromatin is a matter within a chromosome comprising of DNA and protein. The primary proteins in chromatin are histones. Histones help in packaging the DNA in a compact form that fits in the cell nucleus. Changes in chromatin structure are linked to DNA replication and gene expression.
Exercise 1: Patterns of Inheritance
Post-Lab Questions
 Part 1: Monohybrid Cross
Record Punnett squares for Crosses 1A a...