Molecular Phylogenetics

Question 0

What are the steps of molecular phylogenetics ?

Answer 0

1. Get DNA sequence
2. Compare them
3. Make a tree based on nucleotide sequence

Question 1

What is molecular phylogenetics?

Answer 1

Compares DNA sequences b/w organisms

Question 2

Phylogenetic tree

Answer 2

-Can contain info about evolutionary distance by length of branches

Vs cladogram where lengths are arbitrary no meaning

Question 3

Meaning of Phylogenetic tree branches

Answer 3

• Length= evolutionary distance
• describe by time/ number of changes
• number of changes described morphologically or by nucleotide sequence

Question 4

What is bifurcation & when is it used?

Answer 4

• the division of something into 2 branches or parts

- used by cladistics

Question 5

What is multifurcation and when is it used?

Answer 5

• Division of something into more than 2+ branches or parts
• used by molecular methods
• acceptable

Question 6

Rooted tree

Answer 6

One unique node on tree is common ancestor of everything else on tree

• typically an out group
• has a root

Question 7

What is unrooted tree

Answer 7

Depicts relationships b/w members w/out a common ancestor

-typically through computational methods

Question 8

What is computational phylogenetics?

Answer 8

-algorithms: process or set of rules to be followed in calculations can be used for morphological/molecular data
-morphological: must pick and define characters to make a tree
-molecular: characters already defined
MUST BE HOMOLOGOUS

Question 9

Define parsimony.

Answer 9

The adoption of the simplest assumption in the interpretation of data
-occham’s razor

Question 10

Define Occham’s razor

Answer 10

Principle stating that the hypothesis that has the fewest assumptions is best

Question 11

What is traditional phylogenetics?

Answer 11

Uses morphology to make tree

Question 12

What is molecular phylogenetics?

Answer 12

Uses nucleotide sequences to make trees