Ectomycorrhiza

Question 1

What type of plants do ectomycorrhiza typically colonize

Answer 1

Trees, woody plants

Question 2

What percentage of trees are colonized by ectomycorriza compared to plants colonized by endomycorrhiza

Answer 2

10% of trees colonized by ectomycorrhiza; 90% of plants colonized by endomycorrhiza

Question 3

Which phyla of fungus form the majority of ectomycorrhizal relationships

Answer 3

Basidiomycetes

Question 4

Which phyla of fungus form the majority of endomycorrhizal relationships

Answer 4

Ascomycetes

Question 5

True or false: ectomycorrhiza penetrate the root cells of the plants that they colonize

Answer 5

false, they grow around and in between the cells

Question 6

A loose weft of hyphae that is formed around the plant cell

Answer 6

Hartig net

Question 7

Hyphae that are established outside of the root

Answer 7

Mantle

Question 8

Characteristics of roots that are colonized by an ectomycorrhizal fungus

Answer 8

Different color, thicker, lots of dichotomous branching, no root hairs

Question 9

Do ectomycorrhizal fungus show host specificity

Answer 9

No, they do not show a high degree of host specificity

Question 10

Apoplast

Answer 10

the space in between the cells

Question 11

What is delivered into the apoplast from the plant, then taken up by the fungus

Answer 11

Sucrose

Question 12

What are harvested by the fungus from the environment, then delivered into the apoplast to be taken up by the plant

Answer 12

Phosphate, amino acids, and peptides

Question 13

Why is the tree completely dependent on the fungus after colonization

Answer 13

Because the relationship results in the loss of root hairs and encasement of the feeder roots by the fungus, so all minerals that enter the root must enter through the hyphae

Question 14

What percentage of a tree’s net photosynthate is allocated to the fungus

Answer 14

10%

Question 15

What happens to fungi that are grown outside of the ectomycorrhizal relationship?

Answer 15

The do not fruit, grow poorly, and are unable to degrade cellulose (the principal diet of basidiomycetes)

Question 16

How long is the typical life span of an ectomycorrhizal relationship

Answer 16

Three years

Question 17

Two reasons why the ectomycorrhizal relationship eventually ends

Answer 17

The roots outgrow the fungus and the tree roots might be colonized by fungus that is better adapted to the new soil.

Question 18

The interlocking network of fungi and plants that communicate through the fungal hyphae

Answer 18

the “wood-wide-web”

Question 19

Three genera of Basidiomycetes that commonly form ectomycorrhizal relationships

Answer 19

Amanita, Boletus, and Tricholoma

Question 20

Genus of Ascomycete that forms ectomycorrhizal relationships

Answer 20

Tuber

Question 21

Genus of Zygomycete that forms ectomycorrhizal relationships

Answer 21

Endogone (VERY RARE)

Question 22

A “menage a trois” network involving two plants and one fungus where one plant does not photosynthesize

Answer 22

Monotropoid mycorrhiza

Question 23

Which features to monotropoid mycorrhiza and ectomycorrhiza share

Answer 23

A mantle and hartig net

Question 24

A nutrient transfer hyphae that punctures the cell wall, but not the membrane.

Answer 24

fungal peg

Question 25

What does the monotropic plant give to the fungus?

Answer 25

nothing

Question 26

Where does the fungus in a monotropoid mycorrhiza get its carbohydrates

Answer 26

A photosynthesizing third party, usually a pine

Question 27

Examples of the three participants in a monotropoid relationship

Answer 27

Monotropa (monotropic plant), Boletus (fungus), and Pinus (third party photosynthesizer)

Question 28

Why are orchids completely dependent on fungi for the first 2-11 years of life

Answer 28

they go through a non-photosynthetic phase during this time

Question 29

Why are orchids called "mycorrhizal cheaters"

Answer 29

They give nothing back to their fungal benefactor

Question 30

The genus and phylum of the most common orchid mycorrhiza

Answer 30

Rhizoctonia spp. (Basidiomycete anamorph)

Question 31

Why are orchid mycorrhiza considered endomycorrhiza

Answer 31

They have a hyphal structure that penetrates the plant cell wall, then degenerates after a few days

Question 32

Peloton

Answer 32

a dense mass of coiled hyphae that invaginates the membrane within the cell wall of orchid root hairs

Question 33

What is the typical lifespan of a peloton

Answer 33

a few days

Question 34

Why is the orchid mycorrhizal relationship thought to be still evolving

Answer 34

the fungus sometimes infects the orchid, killing the embryo, so it is a balancing act

Question 35

Mycorrhiza that has mantle and branches characteristic of ectomycorrhiza, but also penetrates the cell and forms a peloton.

Answer 35

Erecoid mycorrhiza

Question 36

What characteristics do Erecoid mycorrhiza and ectomycorrhiza share

Answer 36

they both have a mantle and branches

Question 37

Why are Erecoid mycorrhiza called "ectendo" mycorrhiza

Answer 37

They exhibit features of both ecto- and endomycorrhiza

Question 38

Why is it difficult to choose the proper ectomycorrhizal inoculant

Answer 38

a toxic species can cause illness/fatalaties or a desirable food species can be over-harvested

Question 39

Dog shit fungus

Answer 39

Pisolithus tinctorius, an earthball

Question 40

Lichen

Answer 40

a relationship between a fungus and an alga

Question 41

Mycobiont

Answer 41

the fungus, which is the dominant partner and determines the shape of the lichen

Question 42

Photobiont

Answer 42

the alga that lives and photosynthesizes within the fungal thallus, providing carbon compounds

Question 43

Which is the dominant partner in the lichen relationship

Answer 43

The fungus, which is 95% of the biomass

Question 44

Why are lichen considered "balanced parasitism"

Answer 44

The relationship is an exploitation by the fungs; the alga can live perfectly fine on its own but is captured by the fungal component

Question 45

What percentage of food synthesized by the alga is taken by the fungal hyphae

Answer 45

50%

Question 46

Unicellular alga component found in 80% of all lichen

Answer 46

Trebouxia

Question 47

Filamentous green algae that is a component in 10% of all lichen

Answer 47

Trentepohlia

Question 48

Cyanobacteria component found in 10% of all lichen

Answer 48

Nostoc

Question 49

What is the name of a lichen containing all three components

Answer 49

Lobaria

Question 50

What role does the cyanobacteria play in the lichen

Answer 50

It does nitrogen fixation

Question 51

Soredia

Answer 51

Little balls of hyphae-wrapped algae that serve as somatic propagules (reproductive structures)

Question 52

Cephalodium

Answer 52

The internal, brown clump of cyanobacteria

Question 53

Isidia

Answer 53

A finger-like growth containing both the photobiont and mycobiont components that grows up from the thallus and breaks off. (Somatic propagule)

Question 54

Podetia

Answer 54

Large, upright, branched structures that often have cups at the top that may bear soredia

Question 55

98% of the mycobiont components are

Answer 55

Ascomycetes

Question 56

Why are the sexual spores formed by lichens so strange

Answer 56

They do not contain an algal component, so they must find their own appropriate photobiont before they can start a new generation of lichen

Question 57

Many lichen are constantly resynthesized because

Answer 57

The are finding different alga to capture

Question 58

The fungal solution for finding an appropriate photobiont is:

Answer 58

Cleptobiosis

Question 59

Cleptobiosis

Answer 59

stealing a photobiont from another exhisting lichen

Question 60

Lichenicolous lichen

Answer 60

lichen that are growing on top of another because the top lichen has poached the photobiont from the bottom one

Question 61

A flask-shaped structure bearing conidia

Answer 61

pycnida

Question 62

Who determines a lichen's shape

Answer 62

the fungal component

Question 63

Lichen that looks "painted on"

Answer 63

Crustose lichen

Question 64

Lichen with a lobed appearance

Answer 64

Folios

Question 65

Bush-like lichen

Answer 65

Fructiose

Question 66

Lichen with upturned scale-like squamules

Answer 66

Squamulose

Question 67

Loose, powdery, soredia-like material lacking an outer cortex and not producing fruiting bodies

Answer 67

Leprose

Question 68

What happens if a mycobiont is grown without a photobiont

Answer 68

It grows as an undifferentiated mass of hyphae

Question 69

Under what conditions will the fungus and the alga form lichen

Answer 69

When both parties are completely debilitated, the fungus will "embrace" the alga and the alga will "allow" itself to be co-opted.

Question 70

Cell wall proteins that polymerize via hydrophobic interactions, which make the lichen very hydrophobic

Answer 70

Hydrophobins

Question 71

A fungal feeding structure, similar to an arbuscule, that dimples the membrane but doesn't puncture it

Answer 71

Haustoria

Question 72

A disaccharide that interacts with the membrane to create a liquid crystalline form when dehydrated and doesn't leak when rehydrated

Answer 72

Trehalose

Question 73

How much do lichen grow per year and why

Answer 73

1-4 mm/year because they are dried for most of the year.

Question 74

How old is the oldest estimated lichen

Answer 74

4500 years old

Question 75

Measuring the diameter of the largest lichen species on a rock surface to determine how long the rock has been exposed

Answer 75

Lichenometry

Question 76

Which shape of lichen is the most useful to Lichenologists

Answer 76

Crustose, because it is the slowest grower

Question 77

What is the Hawksworth and Rose Lichen Scale used to measure

Answer 77

Air pollution

Question 78

Why are lichen so sensitive to air pollution

Answer 78

Lichen rely on rain to obtain minerals, but acid rain destroys lichen

Question 79

Three important roles that lichen play in nature

Answer 79

Food for animals, used as nests by birds, and soil formation

Question 80

Pedogenesis

Answer 80

Soil formation

Question 81

Cryptobiotic soil

Answer 81

soil that contains lichen with cyanobacteria, which provides the bulk of nitrogen fixation in an ecosystem