Exam 2 Bio

endosymbiosis

phylogenetics

study of evolutionary relationships between organisms

gradualism

time, change slowly

amniotes

vertebrates with fetal membrane (amnion)

taxonomy

the scientific discipline concerned with classifying and naming organisms

binomial

two-part scientific name of a species

first part of the scientific name of an organism

genus

second part of the scientific name of an organism

specific epithet

Carl Linnaeus

founder of taxonomy, introduced system for grouping species

groupings of species (from broad to narrow)

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

taxon

taxonomic unit at any level of hierarchy

phylogeny

the evolutionary history of a species or group of related species

systematics

classifies organisms and determines their evolutionary relationships

what do phylogenetic trees represent?

a hypothesis about evolutionary history, relationships, and patterns of descent

branch point (in a phylogenetic tree)

represents a common ancestor of the descendant species diverging from that point

sister taxa

groups that share an immediate common ancestor

rooted tree

includes a branch to represent the last common ancestor of all taxa in the tree

basal taxon

diverges early in the history of a group and originates near the common ancestor of the group

polytomy

branch from which more than two groups emerge

how do systematists infer phylogenies?

they gather information about morphologies, genes, and biochemistry of living organisms

homologies

similarity due to shared ancestry

organisms with similar morphologies are likely to be _____ _____ _____ than organisms with different structures

more closely related

analogy

similarity due to convergent evolution

convergent evolution

independent evolution of similar adaptations in organisms from different evolutionary lineages

homoplasy (similar to analogy)

characters are similar, but not derived from a common ancestor

phylogenetic trees do not _____…

indicate when species evolved or how much change occurred in a lineage, no phenotypic similarity

______ _______ are used to construct phylogenetic trees

shared characters

_____ _____ can be used to infer phylogeny

homologous characters

cladistics

groups organisms by common descent

cladistics is the ____ ____ of phylogenetics

analytical/statistical part

clade

a group of species that includes an ancestral species and all its descendants

outgroup

species or group of species that is closely related to the ingroup

the outgroup is the group that has…

diverged before the ingroup

systematists

compare each ingroup species with the outgroup to differentiate between shared derived and shared ancestral characteristics

monophyletic (clade)

one group of one ancestor that includes all descendants

paraphyletic

an ancestral species and some, not all, of the descendants

polyphyletic

distantly related species does not include most recent common ancestor

polyphyletic groups are different from paraphyletic groups by the fact that they …

don’t include the most recent common ancestor

shared ancestral character

character that originated in an ancestor of the taxon

shared derived character

evolutionary novelty unique to a particular clade

can a character can be both ancestral and derived?

yes

____ ____ ____ _____’s pink color comes from living prokaryotes

utah’s great salt lake

“bacteria run the world”

Edward O. Wilson

what are masters at adaptation?

prokaryotes

what can thrive almost everywhere?

prokaryotes

what are microscopic but large in numbers?

prokaryotes

prokaryotes are divided into two domains:

bacteria (monera) and archaea

likely Earth’s first organisms

prokaryotes

unicellular, some form colonies

prokaryotes

how big are prokaryotes?

0.5-5 micrometers/μm

three common shapes of prokaryotes

cocci (spheres), bacilli (rods), and spirals

important feature of nearly all prokaryotes cells?

cell wall

what does the cell wall in prokaryotic cells do

maintains cell shape, protects the cell, and prevents it from bursting in a hypotonic environment

what are cell walls made of?

peptidoglycan, network of sugar polymers cross-linked by polylpeptides (strong)

_____ lack peptidoglycan

archaea

what is the gram stain used for

to classify bacteria by cell wall composition

gram-positive

simpler walls with large amount of peptidoglycan

gram-negative

bacteria have less petidoglycan and an outer membrane that can be toxic

antibiotics can target …

peptidoglycan and damage bacterial cell walls

gram-negative bacteria are more likely to be….

antibiotic resistant

capsule

polysaccharide or protein layer that covers many prokaryotes

where is the bacterial capsule located

right outside the bacterial cell wall

pro - (?) karyote - (?)

before the nut

endospores

metabolically inactive, remain viable in harsh conditions for centuries

fimbriae

allow prokaryotes to stick to their substrate or other individuals in a colony

pili (sex pili)

longer than frimbrae, allow prokaryotes to exchange DNA

taxis

ability to move toward or away from a stimulus

chemotaxis

movement toward or away a chemical stimulus

flagella

tough, used by bacteria to move (hook and motor structure)

prokaryotic genome has less ___ than the eukaryotic genome

DNA

most of prokaryotic genome consists of a _____ _____

circular chromosome

chromosome in prokaryotic cells is not surrounded by a membrane, it is located in the _____

nucleoid region

plasmids

smaller rings of DNA in some species of bacteria

what is the foundation of life on earth?

prokaryotes

eukaryotes (definition)

true to the nucleus

eukaryotes are ____-celled organisms

single

what are protists

eukaryotes

organisms in most eukaryotic lineages are ____

protists

protists are colonial. what does this mean?

they coalesce together with one functional purpose and work toward the same goal

protists is the informal name of the group of mostly ______ _______

unicellular eukaryotes

protists exhibit more what than any other group of eukaryotes?

structural and functional diversity

protists can reproduce how?

asexually and through meiosis and fertilization

most nutritionally diverse of all eukaryotes

protists

photoautotrophs

photosynthesize, have chloroplasts

heterotrophs

absorb or ingest large food particles

mixotrophs

combine photosynthesis and heterotrophic nutrition

chemotrophs

chemical energy

______ _____ around the 1970s found bioluminescent animals and vertebrates… what did that discovery do?

Atlantic Rift, it rewrote the way we thought about energy acquisition

how did the vertebrates in the Atlantic Rift get their energy?

micronutrients, volcanic activity, temperature, chemical energy

supergroups of eukaryotes

excavata, SAR, archaeplastida, unikonta

there is considerable evidence that much protist diversity has origins in _______

endosymbiosis

endosymbiosis (a mutually beneficial process)

relationship bw two species where one organism lives inside the cell or cells of the other organism (the host)

Dr. Lynn Margulis

developed the Serial Endosymbiotic Theory (SET), The Origin of Eukaryotic Cells

Serial Endosymbiotic Theory (SET)

chloroplasts and mitochondria evolved from a symbiotic bacteria that lived inside of a larger prokaryote

Earth’s age

~4.5 to 7 billion years

cyanobacteria and protists likely exists on land by..

1.2 billion years ago

small plants, fungi, and animals emerged on land only within the

last 500 million years

plants have diversified into more than

290,000 living species

plants don’t only provide energy, but…

diversity of habitat and places to reproduce

the root of our ancestry evolutionary is

aquatic

algae

photosynthetic protists, not in plant kingdom