Chargaff’s Rule | Eastern Kentucky University

University:
Eastern Kentucky University
Course:
BIO 315 | Genetics
Academic year:

2020
Views:

367

Pages:

1
Author:

apallirasbnc4

NameClass Date Chargaff’s Rule Erwin Chargaff was interested in the work of Avery and did additional research on the structure of DNA. One set of results from his experiments is shown in the data table. Use the information to answer the questions. Percentages of Bases in Five Organisms Source of DNA Streptococcus A T 29.8 31.6 G 20.5 C 18.0 Yeast 31.3 32.9 18.7 17.1 Herring 27.8 27.5 22.2 22.6 Human 30.9 29.4 19.9 19.8 E.coli 24.7 23.6 26.0 25.7 1. Identify Patterns What pattern do you identify in the data? I can see that number of species that have Thymine and which have Adenine are paired, and the number of species that have Guanine, and which have Cytosine are paired. 2. Calculate If a species has 35 percent adenine in its DNA, what is the percentage of the other three bases? Thymine would be 35 percent, Guanine would be 15 percent, and Cytosine would be 15 percent 3. Develop Models All DNA is composed of the four bases shown in the table. How is the pattern in the data useful for developing a model of DNA? The adenine (A) always pairs with the thymine (T), and cytosine (C) always pairs with the guanine (G). So, when scientists model the DNA, the rules help them to pair the DNA bases each other in order.