BISC 132 Exam 2

A fungi cell wall is made up of what?

A fungi cell wall is made up of what?

A polysaccharide called chitin

What term is collectively used to refer to unicellular fungi?

Yeast

What do multicellular fungi produce?

Hyphae

Septate hyphae have walls known as…

septa

What do septa walls in septate hyphae do?

Incompletely separate cells

What are coenocytic hyphae?

One multinucleated cell

What do hyphae form?

Mycelium

What does mycelium do?

Increase surface area for the uptake of nutrients

What are fungi?

Heterotrophs

Most fungi get their nutrients as being what?

Saprobes

How else can mushrooms get their nutrition?

By being either parasitic or a predator

Parasitic fungi are an important plant to what?

Animal pathogens

What different ways can fungi be aerobes/anerobes?

• Obligate aerobes

• Obligate anaerobes

• Facultative anaerobes

How do many fungi reproduce?

Asexually

What are the different ways that fungi can reproduce asexually?

• Fragmentation

• Budding

• Spores

What happens during fragmentation?

A new organism grows from a fragment of hyphae.

In what type of fungi does “budding” occur?

Yeast

How do fungi reproduce asexually using spores?

They release them from their sporangium.

Fungi can also reproduce…

sexually.

What are the steps of sexual mating types of haploid hyphae?

• Plasmogamy (1n)

• Karyogamy (2n)

• Zygote

• Meiosis

• Spores

• Germination

What occurs during plasmogamy?

Cytoplasms fuse

What is the result of plasmogamy?

A dikaryotic cell (N+N)

What happens during karyogamy?

Nucelli fuse to form a single diploid nucleus (2n)

What is produced by karyogamy?

A zygote

A zygote forms haploid spores by what?

Meiosis

What do the haploid spores from meiosis grow into?

Haploid mycellium

What are the five major fungi phyla?

• Chytridiomycota

What are some traits of chytridiomycota?

• Mostly unicellular, some multicellular with coenocytic hyphae

• Only fungi with flagella (on spores)

• Mostly aquatic, some parasites

What is an example of a Chytridiomycota?

Batrachochytrium dendrobatids

What are Batrachochytrium dendrobatids doing?

Devastating amphibian populations across the globe

What are some traits of Zygomycota?

• Coenocytic hyphae

• Form zygotes as part of sexual reproduction

• Diploid (2N) spores that resist harsh conditions

How do Zygomycota spores germinate?

When the conditions are good, they disperse haploid spores from their sporangium.

What is an example of Zygomycota?

Black bread mold

What are some traits of Ascomycota?

• After plasmogamy, a dikaryotic sac-like ascocarp forms. The cell at the tip of this cup is called an ascus.

• There are multiple members

What does an ascus cell do?

Karyogamy, meiosis, and mitosis. This creates 8 haploid ascospores.

What are examples of ascospores?

• Saccharomyces

  • Cerevisiae

  • Bakers/Brewer’s yeast

• Penicillium

  • Chrysogenum

    • Our source of penicillin

What are some traits of Basidiomycota?

• Haploid (1n)

• Primary mycelium undergoes plasmogamy, then mitosis to form dikaroyotic secondary mycelium

• Secondary mycellium is the dominate sturcutre, it grows and forms

  • Grows and forms basidiocarp (mushroom)

• In the club-shaped basidia, in gills of mushroom, karyogamy, meisosi makes 4 haploid basidiospores

  • Basidiospores relesed, grow into new primary mycelium

  • Include shelf fungus and all toadstool type mushrooms (some are edible)

When ascomycetes and basidiomycetes do not reproduce sexually, they are called what?

Imperfect fungi or mold

What do glomeromycotan form through asexual reproduction?

Almost all form Arbuscular Mycorrhizae

Fungi can be found in virtually all ecosystems. What type of relationships do they participate in?

• Mutualism

• Parasitism

• Communsiliam

What is mycorrhizae?

A partnership between the roots of a plant and fungal hyphae (90% of plant species)

What happens during mycorrhiaze?

The fungi uses hyphae to absorb water and mineral nutrients for the plant. In turn, the plant gives sugars from photosynthesis to the fungus.

What are the two types of mycorrhizae?

• Ectomycorrhizae

• Endomycorrhizae

What is lichen?

A symbiotic relationship between a fungus and a partner through photosynthesis.

What occurs to make lichen?

A fungus provides protection and its partner provides sugars through photosynthesis. (mutualism)

What are fungus-growing ants?

Leafcutter ants

What do the leafcutter ants do?

They feed leaves to, care for, and eat fungi.

The fungus that the ants take care of can be considered to be what?

Domesticated through mutualism

What issue rises with human fungal infections?

They are very hard to treat

Protists and humans have issues with treating fungal infections. Why?

They are both eukaryotes

True or False: Antibiotics work to treat fungi infections.

False

Some fungi are important model organisms for understanding what?

Eukaryotes

What are the Kingdom Plantae?

Monophyletic phototrophs that are distinct from red and brown algae due to their different photosynthesis pigments

The earliest plants were aquatic. What were they called?

Green algae that went through both asexual and sexual reproduction

What are the two types of the first plants?

Chlorophytes and Charophytes

Chlorophytes are often…

unicellular.

Which of the first two types of plants are more closely related to land plants?

Charophytes

What are some advantages to early life on land from an evolutionary standpoint?

• Less competition

• More light

• No herbivores

  • At first…

What are some challenges to early life on land from an evolutionary standpoint?

• Need to not dry out

• Need to transport water to photosynthetic organs

• Need to support weight of body

• Sperm needs to get to eggs

All “land plants” have what kind of life cycle?

Haplodiplontic

What are sporophytes?

Multicellular diploids (2n) that are used in the haplodiplontic life cycle.

What are gametophytes?

Multicellular haploids (1n) that are used in the haplodiplontic life cycle.

What are two parts of the haplodiplontic life cycle?

• Sporophytes

• Gametophytes

What is the dominant form of the haplodiplontic life cycle?

Either sporophytes or gametophytes

What are the of the haplodiplontic life cycle?

• Sporophytes (2N) produce unicellular haploid spores by meiosis.

  • These spores divide by mitosis. to form a gametophyte (1N)

• The gametophyte produces gametes (eggs/sperm) through mitosis. These then fuse to form a zygote.

  • These zygotes divide by mitosis to form sporophytes (2N)

What do sporophytes produce through meiosis?

Unicellular haploid spores

What do the unicellular haploid spores do?

Divide by mitosis to form gametophytes (1n)

What does the gametophyte produce through mitosis?

Gametes (eggs/sperm)

Gametes fuse to form what?

Zygotes (2N)

The zygotes created by gametophytes divide by mitosis to produce what?

To produce sporophytes (2N)

The earliest land plants were known as;

• Bryophytes

What are some examples of bryophytes?

• Liverworts

• Hornworts

• Mosses

What are bryophytes?

A prominent gametophyte, sporophyte, can be hard to see. They have no vascular tissue to transfer water or nutrients, so they must be small. They have no roots; rhizoids anchor them to the ground. They also use thalli to do photosynthesis, and their eggs and sperm are produced by gametophytes on distinct structures that can either be on the same plant or on a different individual. They also can only reproduce in moist/wet environments.

Bryophytes are also known as what?

Non-vascular plants

Bryophytes do not have roots, but they rather have (what?) to anchor them to the ground.

Rhizoids

Bryophytes have no leaves but have something that does go through photosynthesis. This is known as what?

Thalli

The eggs and sperm of a bryophyte are produced on what?

Distinct structures on the same plant or on a separate plant.

Bryophytes can only reproduce in what type of conditions?

Wet/rainy conditions as their sperm swims using flagella.

Liverworts reproduce asexually using what?

Gemma cups that detach, flow away with the rain, anchor, and grow into a new gametophyte.

What do hornworts have?

Sphorophyte structures in the shape of a tall, thin horn that helps to disperse spores.

The gametophyte of mosses can be considered to be…

A tangle of photosynthetic filaments on the ground.

What do mosses have that help to elevate the sporophytes?

Stalks that allow them to disperse spores.

Saprobes are a part of what cycle?

The carbon cycle

What are tracheophytes also knwon as?

Vascular plants

What is special about tracheophytes?

They have a vascular system to transport water and nutrients throughout plant in roots, stems, and leaves.

What anchors plants better than rhizoids?

Roots

What helps to make cell walls of plants stronger?

Lignin

What has better surface than thalli, thus resulting in more photosynthesis?

Leaves

The characteristics of being a vascular plant allow for what type of plants?

Larger plants

Taller plants…

access sunlight better

What is more prominent in vascular plants?

Sporophyte

What are the two major groups of seedless vascular plants?

• Lycophytes

In seedless vascular plants, the sperm still has to swim to get to the egg. For this, they require…

a moist environment.

What are some exampeles of lycophytes?

• Club mosses

• Quillworts

• Spike mosses

What are lycophytes also known as?

Fern allies

What are some examples of pterophytes?

• Whisk ferns

• Horsetails

• Ferns

The leaves of a fern develop into something known as a ( ) that unfurls when they grow.

fiddleheads.

What is the life cycle of a fern?

• Sporophyte

  • Releases haploid spores

    • These spores are photosynthetic and independent of the sporophyte.

• Rest of life cycle is typical

What does division spermatophyte mean?

Seeded, vascular plants.

What are some qualities of a sporophyte dominant plant?

• Gametophyte is microscopic (not free-living)