Biology 2

what did Carolus Linnaeus do

classified life’s diversity “for the greater glory of God”

classified life according to morphological characteristics

How do scientists classify life nowadays

molecular characteristics of DNA or proteins

what are morphological and molecular characteristics used in

phylogeny, the evolutionary history of species

taxonomy, the scientific naming and classification of species

what is Carolus Linnaeus most famous for

developing the binomial naming system for naming species using latin

Who added an addition taxon and what is it

Carl woese, domain

Name each taxa in their proper rank (taxon)

domain

kingdom

phylum

class

order

family

genus

species

What are the 3 domains by Carl Woese

bacteria, archaea, eukarya

two main groups of phylogenetic trees

cladogram

phylogram

define cladogram

branch order only important feature and branch length and order of terminal tree are irrelevant

define phylogram

branch order is important and branch lengths are proportional to evolutionary change or time

what does the root tell you in a phylogeny

a root is before the first branch point and represents the most recent common ancestor of all the organisms depicted in that tree

branch points in a phylogeny

represent a dichotomy where an evolutionary relationship is not fully understood which is represented as a polytomy, a branch point with more than 2 descendants

sister taxa

most related and share common ancestor

basal taxon

lineage that diverges early

a clade

monophyletic group that includes an ancestor and all its descendants

paraphyletic group

includes an ancestor and some, but not all of its descendants

polyphyletic group

includes descendants with different ancestors

autotrophs

organisms that produce their own food. these organisms obtain carbon from inorganic sources like CO2

heterotrophs

organisms that consume their food. obtain carbon from organic macromolecules

mixotrophs

organisms that can be both autotrophs and heterotrophs

morphological characteristics

size shape and presence or absence of anatomical features

Describe the hierarchical organization of biological classification.

Many species are within a genus → many genera within a family → many families within an order → many orders within a class → many classes within a phylum → many phyla within a kingdom.

domain

many kingdoms/phyla are within a domain

which domains contain prokaryotic cells vs eukaryotes

bacteria and archaea have prokaryotes and eukarya contain eukaryotes

which domains are sister taxa

archaea and eukarya

define archaea

prokaryotes that live all over the world, including many extreme environments

define bacteria

prokaryotes that include harmful pathogens and beneficial photosynthesizers and symbionts

Euryarchaeote group

halophiles (archaea living in salty conditions), methanogens (archaea that release methane gas)

TACK supergroup/superphylum group includes:

thaumarchaeotes

aigarchaeotes

crenarchaeotes

korarcheotes

thaumarchaeotes

archaea that can oxidize ammonia

aigarchaeotes

archaea that are aerobic and thermophiles

crenarchaeotes

thermophiles (archaea living in hot conditions)

korarcheotes

recently discovered

Proteobacteria

diverse group of gram-negative bacteria that includes, phototrophs, chemotrophs and heterotrophs

chlamydias

parasitic bacteria that only survive inside animal cells

spirochetes

helical bacteria that move like a corkscrew

cyanobacteria

photoautotrophs that perform photosynthesis

gram-positive bacteria

diverse group which lack an outer membrane

biofilm

surface coating colony

how do cells in a biofilm act

cooperatively as a community and share nutrients

what type of membrane do gram-positive bacteria have

single plasma membrane with thick outer layer of peptidoglycan

what type of membrane do gram-negative bacteria have

inner plasma membrane, middle thin layer of peptidoglycan and outer membrane with lipid lipopolysaccharide

cell wall of many prokaryotes

surrounded by sticky capsule or slime layer

fimbriae

short appendages for adhesion

flagella

long appendages that whip to move cell

pili

appendage that pulls cell together during DNA transfer

taxis

directional movement toward or away from stimulus

chemotaxis

directional movement toward or away from chemical

binary fission

one cell divides into two which can each divide

nucleoid

contains DNA genome in cytoplasm

F plasmid

contain fertility genes to make pilus

R plasmid

contains genes that enable antibiotic resistance

3 main mechanisms that prokaryotes use to move genetic material

transformation

transduction

conjugation

transformation

uptake of foreign DNA

transduction

transfer of DNA via phage

Conjugation

transfer of DNA through pilus

obligate aerobes

require oxygen for cellular respiration

obligate anaerobes

die in Prescence of oxygen

nitrogen fixation

some prokaryotes convert nitrogen into ammonia

endospore

dormant form of cell that can withstand harsh environment

protists

mostly unicellular eukaryotic organisms with great structural and functional diversity.

different protists that fit into all four eukaryote supergroups

excavata, SAR, archaeplastida, unikonta

what are the members of excavata characterized by

cytoskeleton, many have an excavated feeding groove

are diplomonads and parabasalids sister taxa?

yes, they have interesting modified mitochondria

Euglenozoans

diverse protists that have a spiral or crystalline rod in their flagella

what ‘troph’ are euglena

mixotrophs

what does the SAR clade consist of

stramenophiles, alveolates, rhizaroans

diatoms

photosynthetic unicellular glass like algae organisms, symmetry, strong

brown algae

multicellular and mostly marine protists

oomycetes

water moulds

dinoglagellates

have a cellulose plate and 2 flagella

apicomplexans

parasites of animals

ciliates

large varied group characterized by their numerous cilia used for moving and feed

ameobas

unicellular organisms found in rhizaria and unikonta, they use pseudopodia to move and eat

forams

have porous shell called a test

cercozoans

have threadlike pseudopodia and some have flagella

radiolarians

look like a star with numerous thread like pseudopodia reinforced with microtubules

supergroup Archaeplastida contains:

red and green algae and land plants, all have plastids

red algae

mostly multicellular

green algae

can be unicellular, divided into two groups chlorophytes and charophytes

supergroup unikonta contains:

protists like fungi and animals

slime moulds

fungus like and cellular or plasmodial

entamoebas

parasidic ameobas

nucleariids

unicellular amoebas that feed on algae and bacteria

choanoflagellates

unicellular colonial protists, characterized by single flagellum surrounded by collar of microvili

protists are either:

photoautotrophs or chemoheterotrophs

fungi are _____

heterotrophs

what type of cell structure do fungi have

unicellular sometimes but mostly multicellular

are type of cellular structures do fungi have

all the typical eukaryotic cells and a cell wall make of chitin and large central vacuoles

what are the network like structures of multicellular fungi called

hyphae

fruiting body

hyphae used for reporduction

mycelium

interwoven mass of hyphae used for feeding

what are specialized hyphae, arbuscules

little trees that grow instead plant root cells to exchange nutrients

haploid spores

spores involved in asexual or sexual reproduction

plasmogamy

two spores meet and fuse cytoplasm’s in sexual reproduction

what does plasmogamy produce

cell called heterokaryon

karyogamy

two different haploid nuclei fuse in this process

produce diploid cell

chytrids are mostly what

aquatic fungi with motile flagellated spores

zoopagomycetes

fungi impact animals, some pathogens, some mutualists

mucoromycetes

phylum mucoromycota

moulds and mycorrhizae