Evolution By Substitution: Amino Acid Changes Over Time

杨利霞

Evolution By Substitution:

Amino Acid Changes Over Time

Evolution By Substitution: Amino Acid Changes Over Time
DNA, or deoxyribonucleic acid, carries the code for life and that code directs the making
of proteins that will carry out the organism’s functions. Proteins are made from twenty
different amino acids and the number and order of those amino acids will determine the
properties and function of the protein. Any alterations in the sequence of amino acids
may have an effect on the function of the protein. The protein may not function as well,
may lose all function, or may possibly function better. It is also possible that the
substitution may not affect the function of the protein at all.
Mathematical analysis of similar proteins in different organisms based on the sequence of
amino acids may give insight into their possible evolutionary history and perhaps even
that of the organisms that contain those proteins. Such analysis may also lead to
explanations of the mechanisms of evolution, which resulted in the natural selection of
these proteins.
Unit Goals and Objectives
Goal: Students will experience the excitement of modern biology from both the
biological and mathematical point of view.
Objectives:
 Relate DNA changes and resulting amino acid substitutions to evolution.
 Develop a deeper understanding of evolution through the study of amino acid
substitution and matrix multiplication.
Goal: Students will explore the connections between the mathematical and biological
sciences.
Objectives:
 Identify the probability for single events.
 Relate the use of a matrix to the probability for compound events and for events
repeated over time.
 Demonstrate a proficiency in multiplying two matrices together and raising a
square matrix to a power.
 Understand the relationship between powers of a matrix and future evolutionary
states.
Goal: Students will experience how mathematical modeling simulates theoretically
behavior of a proposed system.
Objectives:
 Identify state diagrams and their properties.
 Construct a state diagram to describe changes in a system.