Lecture 12

Question 1

coding strand is the one that runs from … to …

Answer 1

5’; 3’

Question 2

… tree: each branch splits into two

Answer 2

dichotomous

Question 3

basal clade: group that is … to all others

Answer 3

least related

Question 4

Why study the evolutionary history of diseases?

• to understand how genetic differences are related to …
• improved diagnostic …, …, … and …
• identify … of new diseases
• elucidate interactions among … and different … or in different …
• describe rate of …
• make predictions about …

Answer 4

pathology; assays; treatments; drugs; vaccines; origins; disease organisms; host species; habitats; evolutionary change; future outbreaks

Question 5

phylogenetic tree: diagram of … among a group of organisms

Answer 5

evolutionary relationships

Question 6

the root of the tree represents the …, and the tips of the branches represent the …. of that …

Answer 6

ancestral lineage; descendants; ancestor

Question 7

The branches of a phylogenetic tree may be represented two different ways;

• … branches: branches will be different lengths based on the number of … or …
• … branches: all branches in the tree are the ..

Answer 7

scaled; evolutionary changes; distance; unscaled; same length

Question 8

for scaled branches, branches that don’t continue moving express …
those that do represent .. species-species that are …

Answer 8

extinct species; extant; still alive now

Question 9

branch length may represent … or rate of …

Answer 9

time; genetic change

Question 10

for many trees, branch length is not scaled at all; only the … is represented

Answer 10

pattern of change

Question 11

When a lineage splits (.. or … event), it is represented as … on a phylogeny. When a splitting event occurs, a … gives rise to two or more daughter lineages

Answer 11

speciation; splitting; branching; single ancestral lineage

Question 12

phylogenies trace patterns of … between lineages. Each lineage has a part of its history that is … to it alone and parts that are …

Answer 12

shared ancestry; unique; shared with other lineages

Question 13

Each lineage has ancestors that are … to that lineage and ancestors that are shared with other lineages–…

Answer 13

unique; common ancestors

Question 14

a clade is a grouping that includes a … and all the … (… and …) of that …

Answer 14

common ancestor; descendants; living; extinct; ancestor

Question 15

clades are nested within one another, forming a …

Answer 15

nested hierarchy

Question 16

taxonomic classification reflects this nested hierarchy: all taxonomic groups should be

Answer 16

true clades

Question 17

the branching pattern of phylogenetic trees does not imply …-all lineages have had .. to evolve, and evolve unique differences since splitting from other lineages

Answer 17

advancement; equal time;

Question 18

some trees indicate when … evolved. These can be … or …

Answer 18

specific characters; morphological; molecular

Question 19

that character is an … for that lineage, so all descendants should … that character, unless it is later … through further …

Answer 19

ancestral trait; share; lost; evolutionary change

Question 20

additional information can be “mapped” onto a phylogenetic tree to look patterns and correlations between … and other …

Answer 20

evolutionary history; characteristics

Question 21

every phylogenetic tree is a …, but many have an abundance of .. supporting them

Answer 21

hypothesis; evidence