BIOL 172 Exam 1

Protists, 4 Supergroups,

What are the levels of Organizations in Biology?

Biosphere, Ecosystems, Communities, Populations, ORGANISMS, Organs/Organ Systems

Evolution =

changes in organisms’ DNA over time

The goals of every organisms are _________+________

survival;reproduction

Taxonomy = ?

classification method

Phylogeny

'“tribe-making”

There is an estimated ____ _______ extant species

8.7 MILLION

The Taxa (DKPCOFGS)

Domain, Kingsdom, Phylum, Class, Order, Family, Genus, Species

How many domains are in the Modern ToL (Tree of Life)?

3 domains

Where are the Eukarya Supergroups in The Taxa?

Between Domain and Kingdom

The ToL is built using _______

Phylogenies

What is a Protist?

Any eukaryote that is NOT a fungus, plant, or animal

What was a protist once classified as?

The Kingdom Protista

A protist is no longer classified together as Kingdom Protista because …..

paraphyletic

Protists are mostly …..

unicellular, NO tissues

What are Protists NOT?

Plants, Animals, or Fungi

“Protist” is paraphyletic, not _______

monophyletic

Protists evolved across all three feeding types which are….

Producers(Autotrophs), Consumers (Heterotrophs), and Mixotrophs

Producers (Autotrophs)

“Self feeding” They make organic molecules(biomolecules) from scratch (CO2 and inorganic reactants)

Consumers (Heterotrophs)

“different feeding” They must consume pre-made organic molecules

Mixotrophs

“Mixed feeding” Can produce AND consume other organisms

Almost all Autotrophs are _____________, using solar energy to make GLUCOSE through photosynthesis.

photoautotrophs

The rest of Autotrophs (Producers) are ________ that are in places like deep-sea hydrothermal vents, geysers, caves, and deep in rock

chemoautotrophs

__________ occurs in some prokaryotes and all plants, but also algae and certain other protists.

Photosynthesis

Almost all ________, including humans, depend on photoautotrophs for food and oxygen.

heterotrophs

Endosymbiosis

one cell engulfs another cell, which becomes an endosymbiont and then in the host cell

________ evolved through 1st Degree endosymbiosis of an aerobic heterotrophic bacterium —- happened ONCE!

Mitochondria

Each type of ____ evolved through endosymbiosis events

Plastid

________ is how PROTISTS evolved from PROKARYOTE ancestor(s). (e.g. Chloroplasts vie 1st Degree endosymbiosis of cyanobacterium → green algae)

Endosymbiosis

Endosymbiosis occurred repeatedly in the evolution of ______

Eukaryotes

In Domain ________, One phylogeny splits all eukaryotes into 4 “supergroups”

Eukarya

The four supergroups of Domain Eukarya

Excavata, SAR clade, Archaeplastida, Unikonta

The 3 members in the Excavata supergroup.

Key characteristics: PROTISTS, UNICELLULAR, “excavated” feeding groove, mostly anaerobic environments with reduced mitochondria

Diplomonads, Parabasalids, Euglenozoans

Diplomonads have a _____-______ _______!

(e.g. Genus species =Human diarrhea parasite from infected freshwater sources)

Non-functional mitochondria ; Giardia lamblia

Parabasalids have reduced mitochondria called __________ → produce H adn ATP anaerobically. Genus species- common STI that infects urinary& reproductive tracts

hydrogenosomes ; Trichomonas vaginalis

Euglenozoans have which unique features? (Excavata supergroup)

spiral or crystalline rod inside their flagella

The Euglenozoans includes ______ and ______

kinetoplastids ; euglenids

The kinetoplastid _______ _____ infects humans and cattle → African sleeping sickness from Tsetse flies (vectors)

Trypanosoma brucei

Trypanosoma brucei evades immune system of host using millions of _____ ____ ____ (VSG’s) expressed sequentially

variable surface glycoproteins

The “___” clade was established entirely by DNA homologies

SAR

The SAR Clade contains 3 related clades which are

Stramenopiles, Alveolates, Rhizarians

This clade includes important autotrophs and some heterotrophs (diatoms, golden algae, brown algae) → uni- & multicellular

hint: part of SAR’s clade

Stramenopiles

Important Unicellular Stramenopiles like _______ are unicellular algae with a unique 2-part glass-like cell wall

Diatoms

Stramenopiles like Diatoms produce _____ of all O2 on Earth

20%

Important multicellular Stramenopiles include ____ ____ (aka “seaweeds” or macroalgae) largest;marine most complex algae

Brown algae

This SAR’s clade includes dinoflagellates, apicomplexans, and ciliates and is named for membrane bound sacs (cortical alveoli) just under the cell membrane

Alveolates

These IMPORTANT Alveolates could be autotrophs, heterotrophs or mixotrophs.

**Some could release toxins in the presence of large fish that cause the “red tide”

Dinoflagellates

__________ are ALL unicellular and are specialized parasites of animals

e.g. Plasmodium → malaria

Toxoplasma → toxoplasmosis

Apicomplexans

Apicomplexans spread through their host as infectious cells called _______

sporozoites

One end of an Apicomplexan cell, the apex contains a _____ __ _________ specialized for attaching to and penetrating host cells and tissues

complex of organelles

4 species of ________ cause malaria in humans'

e.g. Insect vecot = Anopheles mosquitoes

Plasmodium

Toxoplasma induces _________ ___________ in hosts

behaviorial changes

(e.g. A rat willingly shows itself to a cat so cat can eat it and then cat poops and contaminates its next victim)

A large varied group pf mostly living protists are named for their use of cilia to move and feed.

Most well known Paramecium

Ciliates

Ciliates have large macronuclei and small micronuclei, and has Genetic variation (recombination) via ________

conjugation

Conjugation in ciliates is a ..

sexual process, but not sexual reproduction.

two individuals exchange haploid micronuclei

Ciliate reproduction via separate asexual process of ________ ________:

one cell splits into two (mitosis)

binary fission

The supergroup _________ is divided into clades Amoebozoa & Opisthokonta

Unikonta

The Supergroup Unikonta include many protists like ____ _____ and the Kingdom ______ and Kingdom _______

Slime molds

_________ are amoebas that move with lobe- or tube-shaped pseudopodia (foot-like extensions) and include slime molds

Amoebozoans

____________ _____ _____ are amoeba “supercells containing many nuclei that inhabit moist soil or decaying vegetation and feed by phagocytosis (Cell-feeding, engulfing)

Plasmodial slime molds

__________ ________ ______ are microscopic amoeba that feed individual cells but can form multicellular aggregated to migrate as a visible mass and disperse reproductive spores.

Cellular slime molds

Fungi

Single celled or multicellular heterotrophic eukaryotes (most have flagellum)

Fungi’s similarities with plants:

cell walls, non-motile, growth from tips

Fungi’s similarities with animals:

chitin as structural material, and use melanin for skin protection, and heterotrophic

_____ are more closely related to animals than to plants

Fungi

Over 70 species of fungus are _______

bioluminescent

The biggest organism ever is the “______ _______” Armillaria can cover more than 1800 football fields

honey mushroom

The main “body” of the fungus is made up of thin, thread-like filaments that are called ____

hyphae

A mass of hyphae is called a _______

mycelium

__________ fungi lack septa= continuous cytoplasmic mass with hundreds or thousands of nuclei.

Most fungi have hyphae divided into cells by septa with pores allowing for movement of organelles.

Coenocytic

Fungi obtain food by _______ __________ and _________

extracellular digestion ; absorption

Fungi secrete digetsive enxymes into the environment, then absorn the nutrients released; called “_________”

saprotrophic

Most fungi are _______ : live on decaying organisms

decomposers

Some fungi are _______: extract food from living organisms

parasites

A few fungi are _____: paralyze prey

** some unique predatory fungi have specialized hyphae for capturing prey

predators

Fungi can extract or exchange nutrients with plants with specialized hyphae called ______ that penetrate the tissues of their host

haustoria

___________ are mutually beneficial relationships between fungi and plant roots

Micorrhizae

Mycorrhizae are mutually beneficial symbioses between fungi and _______ ______

plant roots

______ are a mutualistic symbioses of fungi+ algae or cyanobacteria

Lichens

The Fungi of a Lichen provides attachment, structure, nutrients, and help anchor soil physically and uses _______

glomalin

Fungi reproduce using sexual or asexual ________

spores

(Almost all) fungi spend most of their lives as ______, becoming ______ only for the purpose of meiosis & sexual reproduction

haploids ; diploid

In Fungal reproduction, asexual reproduction is done by ______ most of the time

haploids

In stressful conditions for Fungal reproduction, they switch to sexual reproduction:

_________ (fusion of +/- cytoplasm) and is followed by _______ (fusion of +/- nuclei → _______ _____)

Plasmogamy ; Karyogamy ; diploid cells

Spores are ____ haploid reproductive cells that are produced sexually (meiosis) or asexually (mitosis)

genderless

______ are widespread in lakes and soils and include decomposers and parasites.

Chytrids

Ergot of rye is caused by an _______ and produces toxins

(think: LSD, gangrene, hallucinations, Most fungi are _____)

ascomycete

Genus species is an ascomyte used to make beer, bread, champagne

Saccharomyces cerevisiae

The 2nd biggest group of fungi

Basidiomycetes

Basidiomycetes include _____, puffballs, and shelf fungi, mycorrhizae, and plant (decomposers of wood)

mushrooms

Chytrids =

MOST DEADLY wildlife pathogen! and are deadly to amphibians

Supergroup ______ includes green algae, red algae, and land plants

Archaeplastida

Green algae is a Paraphyletic group of >7000 species including _______ and _____

chlorophytes and charophytes

Green algae includes ________ + _______ species and require aquatic or damp habitats

unicellular+multicellular

“Most primitive” (simplest) chlorophyte sexual and asexual stages have primitive traits: (motile)

unicellular with flagella

Green algae involved in 3 ways:

Formation of colonies, true multicellular bodies, and repeats division of nuclei coencytic organism (ONE BIG CELL)

In the Kingdom Plantae —Land plants share many traits with green algae but terrestrial (land) plants share 3 key traits ONLY with charophytes:

Rings of cellulose-synthesizing complexes

Structure of flagellated sperm

Formation of phragmoplast

The long-chain structural carbohydrate, cellulose, is synthesized by _____ of protein in the cell membranes of both charophytes and plants

rings

Charophytes and plants use a group of microtubules called a _____ (“fence builder”) to organize the cell plate during cell division (cytokinesis)

phragmoplast

The Pros of Moving onto Land

unfiltered sunlight

more CO2

nutrient-rich soil

escape from aquatic herbivores and pathogens

The Cons of moving onto land

water scarcity: need desiccation protection

full brunt of gravity: needs structural support