Chapter 6. Exploring Evolution and Bioinformatics

Question 1

Synthetic oligonucleotides that can specifically bind ligands. They are useful in biotechnology and medicine and to study molecular evolution.

Answer 1

aptamers

Question 2

molecules that have evolved from a common ancestor. Also referred to as homologous molecules.

Answer 2

Homolog

Question 3

A means of determining the evolutionary relatedness of two proteins in which the two amino acid sequences are systematically aligned with respect to each other to identify regions of significant overlap.

Answer 3

Sequence alignment

Question 4

A sequence comparison tool that yields a list of sequence alignments, each accompanied by an estimate giving the likelihood that the alignment occurred by chance.

Answer 4

BLAST search

Question 5

mutations that replace one amino acid with another similar in size and chemical properties.

Answer 5

Conservative substitution

Question 6

the evolutionary process by which proteins with different properties are derived from a common ancestor.

Answer 6

Divergent evolution

Question 7

the process by which different evolutionary pathways arrive at the same solution to a biochemical problem.

Answer 7

Convergent evolution

Question 8

the process of producing large populations of molecules en mass and then selecting for a particular biochemical property.

Answer 8

Combinational chemistry

Question 9

homologous molecules that are present within different species and have similar or identical functions.

Answer 9

Ortholog

Question 10

conserved residues that are structurally and functionally important and are characteristic of particular families of proteins.

Answer 10

Sequence template

Question 11

a tool for determining evolutionary relationships between amino acid sequences. When two sequences are compared, each substitution is assigned a score based on the matrix. A large positive score corresponds to a substitution that occurs frequently, while a negative score correspond to a substitution that occurs only rarely.

Answer 11

Substitution matrix

Question 12

A branching diagram or tree that shows the evolutionary relatedness of different organisms on the basis of some biological characteristic, such as the amino acid sequences of a family of proteins.

Answer 12

Evolutionary tree

Question 13

homologous molecules that are present within one species. Paralogs often differ in their detailed biochemical functions.

Answer 13

Paralog

Question 14

The exchange of DNA between species that provides a selective advantage to the recipient.

Answer 14

horizontal gene transfer

Question 15

In this substitution, an amino acid is replaced by one that is structurally dissimilar.

Answer 15

nonconservative substitution