Chapter 26 Textbook

Question 1

What two methods do scientists use to determine and categorize evolutionary relationships?

Answer 1

1. morphological characteristics
2. molecular characteristics

Question 2

Morphological characteristics meaning

Answer 2

Relating to the outward appearance of structural features of an organism or its parts. Includes a description of characteristics such as size, shape, colour, number, and arrangement of any other visible feature.

Question 3

Molecular characteristics meaning

Answer 3

Features based on the macromolecular composition of an organism, most notably the content and sequence of DNA and proteins.

Question 4

What are these characteristics used to create?

Answer 4

Phylogenetic trees

Question 5

Phylogenetic Trees meaning

Answer 5

A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms

Question 6

How can phylogenies be used?

Answer 6

As a hypothesis; We can make and test predictions based on the assumption that a phylogeny— our hypothesis—is correct. This is particularly valuable when looking at extinct groups, such as the dinosaurs.

Question 7

Phylogenetic bracketing

Answer 7

Phylogenetic bracketing is a method of inference used in biological sciences. It is used to infer the likelihood of unknown traits in organisms based on their position in a phylogenetic tree.

Question 8

Phylogeny meaning

Answer 8

The evolutionary history of a species or group of related species.

Question 9

Systematics meaning

Answer 9

A scientific discipline focused on classifying organisms and determining their evolutionary relationships.

Question 10

How is ancestry important when studying about organisms today?

Answer 10

Organisms share many characteristics because of common ancestry. As a result, we can learn a great deal about a species if we know its evolutionary history. For example, an organism is likely to share many of its genes, metabolic pathways, and structural proteins with its close relatives.

Question 11

Taxonomy

Answer 11

A scientific discipline concerned with naming and classifying the diverse forms of life.

Question 12

Why is using the common names for organisms confusing?

Answer 12

Common names used in everyday language can often cause confusion because they are too general (refer to more than one species), like a finch for example. Or they do not accurately reflect the organism to the fullest degree. For example a jellyfish isn’t a fish.

Question 13

What system was made to thus avoid confusion when naming organisms?

Answer 13

Binomial Nomenclature

Question 14

How does the Binomial Nomenclature system work?

Answer 14

The first part of a binomial is the name of the genus (plural, genera) to which the species belongs. The second part, called the specific epithet, is unique for each species within the genus. The names are all in Latin additionally.

Question 15

What species are grouped together?

Answer 15

Ones that are closely related are grouped into the same genus.

Question 16

What are the levels of Linnaean Classification?

Answer 16

From broadest to most specific
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 17

What is an analogy for the Linnaean Classification?

Answer 17

The resulting biological classification of a particular organism is some- what like a postal address identifying a person in a particular apartment, in a building with many apartments, on a street with many apartment buildings, in a city with many streets, and so on.

Question 18

Taxon meaning

Answer 18

A named taxonomic unit at any given level of classification.

Question 19

Relationship between taxonomy and phylogenetic trees?

Answer 19

The branching pattern often matches how taxonomists have classified groups of organisms nested within more inclusive groups. Sometimes however, there are differences.

1. Taxonomists occasionally place a species into a genus or some other group that it is not closely related to. This could be because over time the organism lost key traits shared by relatives, and could get reclassified after examining DNA.
2. Linnaean Classification doesn’t expand on the interconnected relationships between groups like mammals, birds, reptiles etc

Question 20

Branch points on phylogenetic trees

Answer 20

The relationships are often are depicted as a series of dichotomies, or two-way branch points. Each branch point (or internal node) represents common ances- tor of the two evolutionary lineages diverging from it.

Question 21

Tree Topology definition

Answer 21

In biology, tree topology is the branching structure of a phylogenetic tree, or evolutionary tree, that shows the evolutionary relationships between organisms. It’s a diagrammatic representation that summarizes the patterns of relatedness between species, independent of the branch lengths.