Chapter 20

Question 1

Adaptive Radiation

Answer 1

When ONE species evolved into many different species VERY quickly!

Question 2

Systematics

Answer 2

Reconstruction and study of evolutionary relationships

Question 3

Cladogram

Answer 3

AKA phylogenetic tree, a family tree among taxonomic groups

Question 4

How many…
Clades?
Branch Points?
Sister Taxa?
Nodes?

Answer 4

Clades: 4
Branch Points: 4
Sister Taxa: 2
Nodes: 4

Question 5

What does it mean if a trait appears on the cladogram at multiple times?

Answer 5

It is an analogous trait

Question 6

Cladistics

Answer 6

Process to arrange tax by homologous characters into clades

Question 7

What type of grouping is a clade?

Answer 7

Monophyletic

Question 8

Monophyletic group

Answer 8

AKA a Clade, is a group of organisms that includes the most recent common ancestor and ALL it’s decendents

Question 9

Paraphyletic group

Answer 9

A group that still contains the most recent common ancestor but NOT all it’s decedents

Question 10

Polyphyletic group

Answer 10

A group of two convergent descendants which do not have a direct common ancestor, they will share similar traits through convergent evolution

Question 11

Synapomorphy

Answer 11

A derived but shared characteristic of trait

Question 12

Rule of Parsimony

Answer 12

In regards to phylogenetic trees, choose the simplest cladogram with the fewest steps or events

Question 13

Polytomy

Answer 13

A branch from which more than two groups emerge: 3 or more Taxa coming off of a node

Question 14

When does Adaptive Radiation usually occur?

Answer 14

After mass extinctions or the recent inhabitation of a new organism into the area

Question 15

Homology

Answer 15

A similar trait due to shared ancestry (but might not share a similar function)

Question 16

Analogy

Answer 16

AKA Homoplasy. A similar trait due to convergent evolution, not because of the same evolutionary path

Question 17

Homoplasy

Answer 17

Analogous structures within different species, which resemble each other and have the same functions, but did not have a common ancestral origin. (They are still analogous traits though!!!)

Question 18

How can a structure be both homologous and analogous?

Answer 18

Bat and bird wings for example are homologous as forelimbs, but analogous as functional wings

Question 19

What do scientists use to establish the phylogeny of a group of organisms (Cladistics)

Answer 19

Homologous Structures

Question 20

Why do you want to avoid polyphyletic grouping?

Answer 20

It is important to know the most recent common ancestor, so scientists will instead reclassify the organisms if the evidence suggests they are polyphyletic

Question 21

Outgroup vs Ingroup on Character Table

Answer 21

The outgroup shares no characteristics with the primitive, while those in the i group share one or more characteristic with it’s primitive ancestor

Question 22

What is an apomorphy represented by on a character table? Pleisomorphy?

Answer 22

An apomorphy is represented by a 1, while a pleisomorphy is represented by a 0

Question 23

Derived Vs Ancestral Traits

Answer 23

Ancestral traits are shared throughout the larger group. Derived traits are present only in a smaller group

Question 24

Autapomorphy

Answer 24

A derived but unique characteristic or trait

Question 25

Apomorphy

Answer 25

A derived characteristic or trait

Question 26

Plesiomorphy

Answer 26

An ancestral characteristic or trait

Question 27

What determines the most parsimonious tree?

Answer 27

The tree with the fewest branches and/or fewest traits on the tree while still being a correct tree

Question 28

Phenetics vs Cladistics

Answer 28

Phenetics is a method of classifying organisms based on structural and morphological characteristics, while Cladistics is a method of classifying organisms based on their ancestry and evolutionary relationships

Question 29

Maximum Parsimony Vs Maximum Likelihood

Answer 29

Maximum Parsimony assumes that the tree that requires the least amount of shared derived characters is most likely, while Maximum Likelihood uses DNA to group organisms

Question 30

Phylogenetic Species Concept

Answer 30

Species is a population or set of populations characterized by one or more shared derived characters

Question 31

Vertical gene transfer

Answer 31

DNA transferred from parent to offspring

Question 32

Horizontal gene transfer

Answer 32

Genetic material transferred from one species to another

Question 33

What are the 5 types of Horizontal Gene Transfer?

Answer 33

Transformation, Transduction, Conjugation, Transfection, Transposons

Question 34

Transformation

Answer 34

When DNA fragment from a dead, degraded bacterium enters a competent recipient bacterium and is exchanged for a piece of DNA of the recipient.

Question 35

Transduction

Answer 35

When a virus transfers genetic material from one bacterium to another

Question 36

Conjugation

Answer 36

When there is a transfer of DNA from a living donor bacterium to a living recipient bacterium by cell-to-cell contact.

Question 37

Transfection

Answer 37

When DNA is introduced to a multicellular organism (eukaryotic cell) by nonviral methods

Question 38

Transposons

Answer 38

Jumping genes!

Question 39

Endosymbiostic Theory of Eukaryotic Orgin

Answer 39

A theory that mitochondria and chloroplasts were once their own primitive bacteria and was engulfed (predator/prey), but then evolved into a eukaryotic cell like we have today

Question 40

Why is it likely that our world started off as an RNA planet?

Answer 40

Because RNA molecules are more stable and replicate more quickly which would have helped create DNA

Question 41

Protocells

Answer 41

Probably some of the first types of cells with lipid bilayers and may have formed fluid filled vesicles with a membrane-like structure

Question 42

The Alkaline Vent Hypothesis

Answer 42

A hypothesis of hydrocarbons that came from deep sea vents that were full of tiny pores. These pores could create a pH gradient which is an essential component in energy producing molecules like ATP

Question 43

How is it proposed that the Horizontal Gene Theory created eukaryotes?

Answer 43

Although the HGT mainly involves prokaryotic cells, it is theorized that eukaryotes evolved from a pool of prokaryotes, some with mitochondria and some with chloroplast