Chp 18 Science

Monophyletic

A clade is made of a __________

all, no

A clade must be monophyletic. This means that it contains an ancestral species and ____ of its descendants, and ___ species that are not descendants of that ancestor.

degrees

A cladogram's branching patterns indicate _______ of relatedness among organisms.

Phylum

A group of classes

Order

A group of families

Class

A group of orders

Genes

A group of similar species

Genus

A group of similar species. It contains five other species of bears, including Ursus arctos, the brown bear or grizzly bear.

Clade

A group of species that includes a single common ancestor and all descendants of that ancestor

Domain

A larger, more inclusive category than a kingdom

Domain term

A larger, more inclusive category than a kingdom

branches, node, shared

A speciation event, in which an ancestral lineage _______ into two new lineages, is the basis for each branch point, or node. Each ____ represents the last point at which the new lineages ______ a common ancestor.

Derived character

A trait that arose in the most recent common ancestor of a particular lineage and was passed along to its descendants. Four limbs, for example, is a derived character for the clade Tetrapoda.

Mitochondria

All eukaryotic cells, for example, have _______, and all mitochondria have their own genes.

Derived character

An _____ is a trait that arose in the most recent common ancestor of a particular lineage, and was passed along to its descendants.

mutate

Because all genes _______ over time, shared genes contain differences that can be treated as derived characters in cladistic analysis.

lose, cautious

Because distantly related groups of organisms can ____ the same character, systematists are _______ about using the absence of a trait as a derived character.

changing

Classification systems have changed dramatically since Linnaeus's time, and hypotheses about relationships among organisms are still ______ today as new data are gathered.

raccoons

DNA analysis revealed that the giant panda shares a more recent common ancestor with bears than with ______. Therefore, the giant panda has been placed in a clade with bears.

new

Darwin's ideas about a "tree of life" suggested a ____ way to classify organisms-- not just based on similarities and differences, but instead based on evolutionary relationships.

clade

Each derived character defines a _____. Hair, for ex, is a defining character for the clade Mammalia.

Long phrases

Early scientific names often used ____ ____ to describe species in great detail. For example, the English translation of the scientific name of a tree might be "Oak with deeply divided leaves that have no hairs on their undersides and no teeth around their edges."

Taxa

Families, Orders, Classes, and Phyla are all _____

Domain

Genetic analysis has revealed that the two main prokaryotic kingdoms are more different from each other, and from eukaryotes, than previously thought. So biologists established a new taxonomic category. What was it?

taxa (singular: taxon)

In addition to naming organisms, biologists try to organize, or classify, living and fossil species into larger groups that have biological meaning. Biologists often refer to these groups as to what?

two

In binomial nomenclature, each species is assigned a ______- part scientific name.

derived

In contrast to Linnaean classification, cladistic analysis focuses on certain kinds of characters, called _____ characters, when assigning organisms into clades.

share

In general, the more derived genetic characteristics two species ______, the more recently they shared a common ancestor and the more closely they are related in evolutionary terms.

Binomial

In the 1730s, Swedish botanist Carolus Linnaeus developed a two-word naming system called ______ nomenclature.

unicellular, prokaryotic

Members of the domain Archaea are _______ and _______, and they live in some extreme environments

unicellular, prokaryotic

Members of the domain Bacteria are _______ and _______. This domain corresponds to the kingdom Eubacteria.

RTA bacteria

Members of the domain ______ live in some of the most extreme environments on Earth.

Heterotrophs, chitin

Members of the kingdom Fungi ______ with cell walls containing _____.

kingdom

Multicellular organisms that move about are placed in the _____ Animalia.

New, new

Over the years, ____ information and ____ ways of studying organisms have produced major changes in Linnaeus's original scheme for organizing living things.

Seven

Over time, Linnaeus's original classification system would expand to include ____ hierarchical species, genus, family, order, class, phylum, and kingdom.

Protista

Quotes are put around kingdom "_____" to indicate that it is not a monophyletic group.

Cladogram

Shows relative degrees of relatedness among lineages.

6

The ___- kingdom system of classification includes the kingdoms Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia.

common

The bottom, or "root," of the tree represents the _______ ancestor shared by all organisms on the cladogram.

modification

The concept of descent with _______- led to phylogeny- the study of how living and extinct organisms are related to one another.

Eukarya

The domain containing all organisms that have a nucleus

Bacteria

The domain containing organisms that are prokaryotic and unicellular

Genus

The first part of the name-Ursus- is the ____ to which the organism belongs.

group

The goal of phylogenetic systematics, or evolutionary classification, is to ______ species into bigger categories that reflect lines of evolutionary descent, rather than overall similarities and differences

Catchall

The kingdom Protista has long been viewed by biologists as a "_______" group of eukaryotes that could not be classified as fungi, plants, or animals.

last

The lowest node represents the ____ common ancestor of all four-limbed animals- members of the clade Tetrapoda.

Eubacteria and Archbacteria

The monerans were placed in what two kingdoms?

Binomial nomenclature

The name Ursus arctos is an example of the two-part scientific name given in the ______ system.

Systematics

The science of naming and grouping organisms

Systematics

The science of naming and grouping organisms is called what?

first

The scientific name usually in Latin. It is written in italics. The ____ word begins with a capital letter, and the second word is lowercased. The polar bear, for example, is called Ursus maritimus.

habitat

The second part of a scientific name- maritimus for polar bears- is unique to each species and is often a description of the organism's _______ or of an important trait.

Phylogeny

The study of how living and extinct organisms are related to one another

more

The use of DNA characters in cladistic analysis has helped to make "evolutionary tress: ____ accurate.

Family

Under Linnaeus' classification system, similar genera were placed into a larger category called a _______

kingdom, phylum, class, order, family, genus, species

What are the seven taxa?

because they vary among languages and from place to place. For example, the names cougar, puma, panther, and mountain lion can still be used to indicate the same animal- Felis Concolor.

Why are common names confusing?

Linnaeus

________ grouped organisms into larger taxa overall similarities and differences

Clade

a group of species that includes a single common ancestor and all descendants of that ancestor- living and extinct.

Eukarya

consists of all organisms that have a nucleus =eukaryotes. It comprises the 4 remaining kingdoms of the six-kingdom system: "Protista," Fungi, Plantae, and Animalia.

Cladogram

links groups of organisms by showing how evolutionary lines, or lineages, branched off from common ancestors