Environmental Microbiology - Exam 4

Protists

eukaryotes with the taxonomic classification in flux

Protists is a ___ grouping

artificial

Protists are not

monophyletic

Protists are typically

unicellular

Stramenopiles include

oomycetes, diatoms, golden algae, and brown algae

Brown algae includes

kelp and brown seaweeds

Stramenopiles have both

chemoorganotrophic and phototrophic members

All stramenopiles have ____ at some point in their life cycle

heterokont flagella

Heterokont flagella

one short, small flagella and one large with flagellar hairs

There are over _____ species of diatoms

100,000

Diatoms are found in both ____ habitats

marine and freshwater

Diatom cell walls are made of

silica

Diatom cell walls are called

frustules

There is a diversity of diatoms in nearly every

natural water source

Diatoms appeared on Earth about ___ years ago

200 million

Diatoms are important to

marine primary production and global carbon cycling

Marine planktonic diatoms produce ____ of organic ocean carbon

40-50%

Diatoms store

photosynthate in lipids (biofuels)

Oomycetes are also called

water molds

Oomycetes are called water molds because of their

filamentous growth and coenocytic (aseptate) hyphae

Oomycete cell walls are made of

cellulose

Oomycetes caused the

Irish Potato Famine

Oomycetes can cause disease in

fish

Golden algae is also called

chrysophytes

Most golden algae are ___ cellular

uni

Some golden algae are

colonial

Golden algae are named for their

color

Golden algae color comes from

chloroplast pigments dominated by fucoxanthin

Brown algae habitat

marine

Brown algae are ___ cellular

multi

Haptophyta were formerly in

Stramenopila

Coenocytic

no septa in hyphae

Haptophyta are

planktonic photosynthetic protists

Coccolithophore and Foraminifera fuction

precipitate calcium carbonate

CaCO3

Calcium carbonate

Coccolithophores and Foraminifera produce calcium carbonate for their

coccoliths

Coccoliths

ornate calcite scales

Coccolithophore and Foraminifera calcium carbonate formation influences

Earth’s carbon budget

How do Rhizaria obtain nutrients?

Predatory or mixotrophs (host algal symbionts)

Rhizaria have ___ morphology

amoeboid

Rhizaria amoeboid morphology is distinnguished by

pseudopodia

Rhizaria are important to the

ocean carbon cycle

Most Rhizaria skeletons are made of

siliceous material or calcium carbonate

Threadlike pseudopodia are also called

axopodia

Rhizaria use pseudopodia to

move and feed

Rhizaria feed by

endocytosis

Endocytosis

Use mucous coated axopodia to entrap prey

Foraminifera are exclusive to ___ habitats

marine

Foraminifera is the only eukaryote that

reduces nitrate to nitrogen gas

Foraminifera form

tests

Tests

shell-like structures

Tests are made of

organic materials

Tests are reinforced with

calcium carbonate

White Cliffs of Dover are formed from

fossilized foraminifera tests

Radiolarians are mostly in ____ habitats

marine

Radiolarians are ____trophic

hetero

Radiolarian tests are made of

silica

Radiolarians are named for their

radial symmetry of tests

Chlorarachniophyta are ___ trophic

photo

Chlorarachniophyta are ___ - like

amoeba

Chlorarachniophyta have _____ chloroplasts

atypical

Chlorarachniophyta’s atypical chloroplasts are a product of

secondary endosymbiosis

Chlorarachniophyta chloroplasts have ___ membranes

four

Chlorarachniophyta chloroplast membranes are derived from

engulfed eukaryotic algae

Chlorarachniophyta chloroplasts also contain a

nucleomorph

Chlorarachniophyta nucleomorphs are the remnent of

engulfed algae

True fungi are

eukaryotic spore-bearers

True fungi are ____ trophs

chemoorganohetero

True fungi use ____ for nutrients

absorptive nutrition

True fungi are (relationship)

parasitic, mutualist saprophytes

True fungi release

degradative enzymes

True fungi lack

chlorophyll

True fungi reproduce

sexually and asexually

Mycology

study of fungi

Mycologists

scientists who study fungi

Mycoses

diseases caused by fungi

Mycotoxicology

study of fungal toxins and their effects

Fungi are important to

fermentation, organic acids, drugs, antibiotics, and immunosuppressive agents

Fungal antibiotics

penicillin and cephalosporin

Fungal immunosuppressive

cyclosporin

Fungal organic acid

citric acid

Fungal drug

cortisone

Fungal fermentation

yeast

There are ____ described fungal species

90,000

There are possible ____ fungal species

1.5 million

Fungal cell walls are made of

chitin

The name Chitin is derived from

a french word meaning “covering”

Chitin chemical formula

C8H13O5N

Second most abundant polysaccharide in nature

Chitin

Most abundant polysaccharide in nature

cellulose

About ___ tons of chitin are produced each year in the biosphere

1 billion

Chitin is a long-chain polymer of

N-acetylglucosamine

The fungal cell wall is ___ glycoproteins

20%

The fungal cell wall is ___ polysaccharides

80%

beta-glucans make a ___ cell wall

stiff

Glycoproteins are ____ linked to additional polyssacharides

covalently

Glycoproteins determine ____ of cell wall

properties

Glycoproteins are

antigenic

Antigenic

hides inner wall components from host immune systems

Main bulk of cell wall

matrix