Apologia Biology Module 04 Review

Front 1

Fungi can be saprophytic or parasitic, but either way they digest their food in the same way. Describe this digestion.

Back 1

Whether saprophytic or parasitic, fungi digest their food outside of their bodies. The fungus grows on and in its food, secreting a chemical onto the food that digests it before it is ingested. The digested food is then absorbed into the cells of the fungus, as a quick source of nutrition and energy.

Front 2

What part of fungus is often most harmful?

Back 2

If a fungus is harmful to other creatures, it is often the substances that the fungus excretes for extracellular digestion which are responsible for the harm that it inflicts.

Front 3

All fungi reproduce by making spores. True or False?

Back 3

True. Most fungi have other means of reproduction at their disposal as well, but they all have this mode of reproduction in common.

Front 4

The mycelium is NOT a root system for the mushroom.

Explain this statement!

Back 4

Although the hyphae might look a lot like roots, there are many differences between a root system and the mycelium of a mushroom. A root system, for example, has one purpose: to pull nutrients and water from the soil so that they can be transported to the rest of the plant. The mycelium of the mushroom, on the other hand, is the main part of the mushroom.

Whereas the root system is really just an extension of the tree, a mushroom's stalk, cap, and gills are really just an extension of the fungus's main body - the mycelium.

Front 5

In regards to cells, kingdom Fungi is unique. In what way?

Back 5

Even when a fungus is composed of septate hypha, its cells are not completely separated from one another, because the pores in the cell walls allow cytoplasm to be passed between the cells.

Front 6

All fungi reproduce by sporophores or stolens. True or false?

Back 6

False. Many fungi do not form sporophores or stolons at all.

Front 7

An organism eats food and then digests it. Does this organism belong to kingdom Fungi? Why or why not?

Back 7

No, the organism is not a part of kingdom Fungi. Fungi digest their food before eating it. This process, called “extracellular digestion,” is common to all fungi.

Front 8

A farmer tries to remove a patch of mushrooms from his field by pulling all of the stalks and caps in the patch out of the ground. Why has the farmer really not gotten rid of the fungus?

Back 8

The stalks and the caps are not the main parts of the mushroom. The mycelium, which is underneath the ground, is the main body of the fungus. Even though the farmer removed the stalks and caps, the mycelium is still there. It will produce more stalks and caps later on.

Front 9

A fungus produces haustoria (plural of haustorium). Is it saprophytic or parasitic?

Back 9

Only parasitic fungi produce haustoria, so the fungus must be parasitic. Since a haustorium's job is to invade a living cell and draw nutrients from it, there is no reason a saprophytic fungus would produce a haustorium.

Front 10

What job does the fruiting body of a fungus perform?

Back 10

The fruiting body holds and releases the spores for reproduction. Once all spores are released, the fruiting body withers and dies.

Front 11

Spores of a fungus give rise to offspring that are identical in every way to the parent. Were the spores formed asexually or sexually?

Back 11

The spores result from asexual reproduction, because asexual reproduction results in offspring that are identical to parents.

Front 12

Kingdom Fungi is divided into six phyla:

Back 12

Basidiomycota,
Ascomycota,
Zygomycota,
Chytridiomycota, Deuteromycota, and Myxomycota

Front 13

How are fungi placed within the six phyla?

Back 13

Organisms are placed within each phylum based mostly on their sexual reproduction.

Front 14

The last phylum in kingdom Fungi, Myxomycota, is rather controversial. Why is it considered controversial?

Back 14

Since the slime molds resemble protozoa during a part of their life cycle and fungi during another part of their life cycle, there is much controversy as to whether to place these creatures in kingdom Protista or kingdom Fungi.

Front 15

What happens during the button stage of development?

Back 15

At this point, the hyphae begin filling with water quickly, and eventually the stipe and cap of the mushroom break through the membrane. The hyphae fill with water so quickly during the button stage that the stipe and cap of a mushroom can literally "pop up" out of the membrane overnight.

Front 16

Once the fruiting body of the mushroom releases all of its spores, the fungus withers and dies. True or false?

Back 16

False. Just the fruiting body withers and dies. The fungus is still very much alive, because the mycelium is still digesting and absorbing nutrients below the surface.

Front 17

What part of the mushroom do we eat?

Back 17

the fruiting body

Front 18

The genus Amanita contains mushrooms that are commonly called "destroying angel" mushrooms. What does that mean?

Back 18

These pure white mushrooms carry a poison that is deadly to humans. If you eat one of these mushrooms, it tastes quite normal. However, after eating one of those mushrooms, you can die in as little as 16 hours! There is virtually nothing that can be done to treat a person who has eaten these deadly mushrooms.

Front 19

Are fairy rings magical? Why or why not?

Back 19

When a fungal mycelium begins to grow in an area, it eats the remains of dead organisms. As it eats, it grows and reproduces. Eventually, the mycelium will spread out in all directions, making a relatively circular patch of hyphae. Once the hyphae in the center of the circle eat up all of the remains of dead organisms, there is no more food for them, and they die. The hyphae at the edge of the mycelium, however, still have food, because they haven't existed for as long as those at the center, and they therefore have not used up the food in their area. As a result, they continue to live, and the mycelium becomes ring-shaped. When it is time to reproduce, then, the ring produces fruiting bodies, forming a fairy ring.

As time goes on, the mycelium continues to grow outward, and the inner hyphae continue to die because they use up their food. As a result, the mycelium retains its ring shape, but the ring gets larger in diameter.

Front 20

Why is it unlikely to find dense patches of puffballs?

Back 20

The puffball spores, which are as fine as dust, are often carried on the wind for several miles before they hit the ground.

Front 21

A mushroom is in its button stage. Has it released its spores yet?

Back 21

No. The button stage comes before the stipe and cap are formed. Since the spores are released from the gills in the cap, a mushroom cannot release its spores until the stipe and cap are formed.

Front 22

One major characteristic that separates the members of phylum Basidiomycota into different subgroups is the structure in which the fungi form their basidia. Where are the basidia formed in mushrooms? What about in puffballs? Where are they formed in shelf fungi?

Back 22

In mushrooms, basidia form on the gills of the cap. In puffballs, they form inside the membrane of the fruiting body. In shelf fungi, they form in the pores of the fruiting body.

Front 23

The members of phylum Ascomycota are both single-celled creatures and multicellular organisms. True or False?

Back 23

True.

Front 24

A single-celled organism asexually reproduces by duplicating its nucleus, causing a bulge to form in its plasma membrane, transferring the copied nucleus and some cytoplasm to the bulge, and then separating the bulge into a small cell. The small cell grows to the size of the parent in a day or so. How does this compare to the budding that takes place in yeasts?

Back 24

It is very similar, but not identical. For yeasts, the bud typically does not detach itself until after it is fully grown.

Front 25

Bread rises because of the fermentation process. Since this process produces both alcohol and carbon dioxide, why don't you get drunk when you eat bread?

Back 25

Baked bread does not have alcohol in it because the heat of the baking process evaporates the alcohol. Thus, even though alcohol is formed during the making of bread, it is removed by the heat of the baking process.

Front 26

Phylum Zygomycota contains fungi that reproduce in three ways. What are they?

Back 26

1. They can asexually reproduce when a stolon lengthens and forms new filaments. The new filaments become a new mycelium and thus a new fungus.

2. Another form of asexual reproduction involves the production of sporangia (from aerial hyphae) that release spores.

3. Finally, hyphae can fuse together and sexually reproduce to form a zygospore that can then mature into another fungus.

*****Although the latter form of reproduction is what separates these fungi from the ones in the other phyla, all three means of reproduction are used.*****

Front 27

Why should you put the rest of a loaf of bread away immediately after pulling out what you need?

Back 27

Because these bread mold fungi have so many reproductive modes at their disposal, their spores are in the air virtually everywhere. If you leave bread out in the open, bread mold spores will eventually land on it and, within a matter of days, the growing mold will be noticeable.

Front 28

A bread mold forms a stolon for reproduction. Is it reproducing sexually or asexually?

Back 28

Stolons are an asexual means of reproduction, so the mold is reproducing asexually.

Front 29

A fungus forms a fruiting body. Is it likely to be a bread mold?

Back 29

No, bread molds do not form a fruiting body. In sexual reproduction, they form an underground zygospore that grows into a new mold. They do have sporangiophores that form asexual spores, but those are not fruiting bodies; they are just specialized aerial hyphae.

Front 30

Phylum Chytridiomycota ...... What characteristic sets them apart and qualifies them to be in this separate phylum?

Back 30

The characteristic that sets the members of this phylum apart from the rest of the fungi is the fact that their spores have flagella.

Front 31

Why is phylum Deuteromycota considered a “holding area?"

Back 31

If a fungus is studied and scientists cannot determine a sexual reproductive phase in its life cycle, it is placed in this “phylum” until it can be better classified. The reason we put phylum in quotation marks here is that many biologists don't really consider this classification group a true phylum. Instead, they consider it a “holding area” until more can be learned about the fungus.

Front 32

Some scientists say that phylum Deuteromycota “has no taxonomic status.” Why?

Back 32

the reason this classification has no taxonomic status is because biologists assume that all fungi have a sexual mode of reproduction. This, of course, could very well be an incorrect assumption, and perhaps this should be a true phylum.

Front 33

A biology teacher once said, “The only thing imperfect about the imperfect fungi is our knowledge of them.” What does the biology teacher mean?

Back 33

The fact that a fungus is called imperfect means that we simply do not know about its sexual reproduction. Since we do not know about an aspect of its life, our knowledge of it is imperfect.

Front 34

In medical journals these days, there is a lot of concern about the overuse of antibiotics. Doctors think that since antibiotics are so effective, they are prescribed far too often for patients. Why are doctors worried about overuse of antibiotics?

Back 34

The more an antibiotic is used, the more likely the chance of bacteria (or other pathogen) strains immune to the antibiotic will form. If that strain reproduces and is spread, a new antibiotic must be made to destroy that strain of bacteria (or other pathogen).

Front 35

Most of the time, you will see slime molds in which stage? Where can you find them?

Back 35

In their feeding stage, when they resemble colonial protozoa. They usually can be found on the bark of decaying logs or between the layers of leaves on the floor of a forest.

Front 36

What color are slime molds?

Back 36

Slime molds are usually white, red, orange, or yellow.

Front 37

Slime molds are stationary. True or False?

Back 37

False. Slime molds can move about as a unit in search of food.

Front 38

What causes slime molds to enter their reproductive stage where they resemble fungi?

Back 38

When the food supply is exhausted or when unfavorable conditions occur, the slime mold will produce fruiting bodies that are best described as sporophores. These sporophores contain spores that are released to find new sources of food. If they find a new source of food, they will grow and reproduce to form a new slime mold. Some slime molds produce motile spores (spores that can move on their own), while others produce nonmotile spores (spores that cannot move on their own).

Front 39

What is the main feature of a slime mold's habitat? (the most important thing)

Back 39

Probably the main feature of a slime mold's habitat is water. Wherever dead trees, bark, or leaves are kept moist, slime molds are almost certain to grow.

Front 40

A biologist observes a slime mold only during its feeding stage. In what kingdom will the biologist most likely classify it?

Back 40

Since slime molds in their feeding stage resemble protozoa, the biologist will most likely classify it in kingdom Protista

Front 41

Where do lichens grow?

Back 41

As a result of this mutualistic arrangement, you can find lichens where other organisms cannot survive. They are commonly found growing on dry rocks, brick walls, fences, and trees. In certain cold, snowy regions, lichens grow so large that they can cover a few square miles!

Front 42

True or False? The fungus of a lichen can live without the alga.

Back 42

False! The fungus NEEDS the alga because it produces the food.

Front 43

What is special about the mycelium of a fungus that makes it a desirable "friend" for a root system?

Back 43

in order to absorb minerals effectively from the soil, an organism must be wide and thin. This is how the mycelium of a fungus grows. This is not, however, the way that a root system grows. Roots usually grow thick and long, trying to go deep into the soil. Since the mycelium of the fungus has the ideal structure for absorbing minerals, it does so in exchange for food.

Front 44

Suppose a biologist were to separate the fungus spores from the alga spores in a soredium. Could the fungal spores develop into a free-living fungus? Could the spores from the alga develop into a free-living alga?

Back 44

The spores from the fungus could never grow into a free-living fungus, because the fungus in a lichen (that's where a soredium comes from) has no food supply without the alga. The alga would be able to live on its own, because the fungus simply gives it support and protection. The alga can live without that. It will not be as prolific as it could be with the fungus, but it can live on its own.

Front 45

There are some scientists who have studied the effect of air pollution on fungi. They conclude that air pollution destroys fungi at a much higher rate than it destroys other organisms. These same scientists say that if air pollution kills too many fungi, trees and other plants will begin to die as well. Why?

Back 45

Because nearly 80% of plants have a symbiotic relationship with the mycelia of fungi, if fungi die off, the trees will no longer be able to participate in the symbiotic relationship. The fungi help trees absorb vital minerals from the soil. Without the aid of the fungi, the trees will not be able to absorb enough minerals, and they will begin to die.

Front 46

Which of the following characteristics or structures exist for the vast majority of fungi? Which are
present in only a few species?


extracellular digestion sporangiophores
motile spores
stolons
mycelia
septate hyphae
chitin
hyphae cells
caps and stalks
haustoria
rhizoid hyphae

Back 46

Characteristics common to the majority of fungi were discussed in the section entitled “General
Characteristics of Fungi.” It was noted, however, that of the specialized hyphae, only rhizoid hyphae
are common to the vast majority of fungi.


Common to the majority of fungi:

extracellular digestion
chitin
mycelia
hyphae
cells
rhizoid hyphae

Present in only some:

stolens
caps and stalks
sporangiosphores
haustoria
motile spores
septate hyphae

Front 47

. Some biologists say that a mushroom is much like an iceberg, because only about 10% of an
iceberg is visible from the surface of the ocean. What do they mean?

Back 47

Typically, we see only the fruiting body of a mushroom. Like an iceberg, that visible part is only a
small fraction of the total mushroom, because the mycelium is the largest component of a mushroom.

Front 48

What is the difference between septate and nonseptate hyphae?

Back 48

Septate hyphae have cell walls to separate the cells while non-septate hyphae do not.

Front 49

What is the function of the following specialized hyphae?
rhizoid hyphae stolon sporophore haustorium

Back 49

Rhizoid hyphae support the fungus and digest the food; a stolon asexually reproduces; a sporophore
releases spores for reproduction; a haustorium invades the cells of a living host to absorb food directly
from the cytoplasm.

Front 50

rhizoid hyphae stolon sporophore haustorium~ which are aerial?

Back 50

. Stolons and sporophores are aerial. Aerial hyphae are not imbedded in the material upon which the
fungus grows. In order to perform their jobs, rhizoid hyphae and haustoria must be imbedded in the
material.

Front 51

What is the difference between a sporangiophore and a conidiophore?

Back 51

A sporangiophore produces its spores in an enclosure; a conidiophore does not.

Front 52

Give the main characteristic associated with each of the phyla of kingdom Fungi:

Basidiomycota,
Ascomycota, Zygomycota, Chytridiomycota, Deuteromycota, and Myxomycota.

Back 52

Basidiomycota: Form sexual spores on club-like basidia

Ascomycota: Form sexual spores in sac-like asci

Zygomycota: Form sexual spores where hyphae fuse

Chytridiomycota: Form spores with flagella

Deuteromycota: Fungi with no known method of sexual reproduction

Myxomycota: Fungi that look like protozoa for much of their lives

Front 53

Describe each of the stages (in chronological order) associated with the life cycle of a mushroom,
starting with the formation of a mycelium.

Back 53

A mushroom begins life as a small mycelium that grows from spores which have come from another
mushroom. As the mycelium begins to grow, it might encounter a compatible mycelium. As the two
mycelia begin to intertwine, their hyphae will sexually reproduce. Eventually, the newly-produced
hyphae will form a complex web and enclose themselves in a membrane. When the hyphae are formed
in the membrane, we say that the mushroom has reached the button stage of its existence. At that
point, the hyphae begin filling with water quickly, and eventually the stipe and cap (the fruiting body)
of the mushroom break through the membrane. The fruiting body of the mushroom releases its spores,
which will grow into new mycelia if they land in suitable habitats.

Front 54

What is the main difference between shelf fungi, puffballs, and mushrooms?

Back 54

The main difference is where they form their spores. Mushrooms form spores on basidia that exist
in the gills of the cap, puffballs produce spores on basidia enclosed in a membrane, and shelf fungi
produce spores on basidia in pores on the fruiting body.

Front 55

What is an alternate host? List a type of fungus that uses one.

Back 55

An alternate host is used by a parasitic fungus at some stage in its life. It is not the host that the
fungus spends most of its life on; it is simply a temporary host that is necessary for a certain part of the
fungus’ development. Rusts use alternate hosts.

Front 56

. What type of fungus is best known for fermentation? To which phylum does it belong?

Back 56

Yeast are best known for fermentation. They belong to phylum Ascomycota

Front 57

How is budding different from the asexual reproduction in bacteria?

Back 57

In budding, the offspring stays attached to the parent until it has grown. In bacterial asexual
reproduction, the offspring grows on its own.

Front 58

Name at least two pathogenic fungi and the maladies that they cause.

Back 58

There are many pathogenic fungi. You need only list two:

1) rusts - crop damage
2) smuts - crop damage
3) ergot of rye (Claviceps purpurea) - death
4) Cryphonectria parasitica - chestnut blight
5) Ophiostoma ulmi - Dutch elm disease
6) Synchytrium endobioticum – potato wart

Front 59

. Describe the three ways a bread mold can reproduce. In each case, specify whether the
reproduction is sexual or asexual.

Back 59

Bread mold can asexually reproduce when a stolon elongates and eventually starts another
mycelium. It can also asexually reproduce when an aerial hypha forms a sporophore (typically a
sporangiophore). Sexually, bread molds reproduce when two mycelia form a zygospore.

Front 60

What puts a fungus into phylum Deuteromycota?

Back 60

If we do not know what its sexual mode of spore formation is, we place the fungus in phylum
Deuteromycota.

Front 61

. What can happen when an antibiotic is used too much?

Back 61

If an antibiotic is used too much, resistant strains of the pathogen it is supposed to destroy can be
formed.

Front 62

Name the genus of the fungus that produces penicillin.

Back 62

. Penicillin is extracted from a fungus in genus Penicillium.

Front 63

When a slime mold is a plasmodium, it resembles organisms from what kingdom?

Back 63

In its feeding stage, a slime mold is a plasmodium. During that time, it resembles organisms from
kingdom Protista.

Front 64

. What is the easiest way to get rid of slime molds?

Back 64

Slime molds must have water to survive. Keep the habitat dry, and all slime molds will die.

Front 65

What are the two major forms of mutualism in which fungi participate? Describe each
relationship and the job of each participant in that relationship.

Back 65

. Fungi participate in mutualism by forming lichens and mycorrhizae. A lichen is a mutualistic
relationship between a fungus and an alga. The alga produces food for both creatures via
photosynthesis, and the fungus supports and protects the alga. Mycorrhizae are mutualistic
relationships between a fungus’ mycelium and a plant’s root system. The mycelium takes nutrients
from the root while it collects minerals from the soil and gives them to the root.

Front 66

What is a soredium?

Back 66

A soredium is the specialized spore produced by most lichens. It contains spores for both the
fungus and the alga.