In Zygomycota, after sexual reproduction, meiosis occurs at germination. Why?
So that spores produced asexually within the new sporangium are haploid.
Homothallic
self-fertile species
heterothallic
require + and - strains for sexual reproduction
Zygosporangia
In phylum Zygomycota, thick-walled structures in species that reproduce sexually, zygospores develop in these
Zygospores
Zygomycota
sexual reproduction
Sexually produced resting spores
Sporangiophore
"Sporangium bearer"
Sturdy erect branch formed from the rhizoid/stolon point
produces a spherical sporangium at its apex
Zygomycota Rhizopus are composed of _______. The coencytic hyphae growing through substrate develop ______ that form _______ whenever their tips come into contact with the substrate.
mycelium
stolon
rhizoids
Why is Fungi important?
Decomposer
Medically
Economically
Pathogens
Symbiotic relationships with plants
Hyphae
Fungal filaments
Mass of hyphae are called_____?
Mycelium
Mycology
Study of fungi
septa (septum-singular)
partitions or crosswalls dividing fungi
Note: hyphae that have this are septate
Coencytic
AKA: a-septate
hyphae lacking septa, "contained in a common cytoplasm"
multinucleate
Explain the nature of hyphae, method of asexual an d sexual reproduction, and the common plant diseases of Phylum: Chytridiomycota
Hyphae: Aseptate/coenocytic
Asexual reproduction= zoospores
Sexual reproduction= NONE
Common diseases= Brown spot of corn, crown of wart alfalfa, black wart of potato
Explain the nature of hyphae, asexual and sexual reproduction and common plant diseases for Phylum: Zygomycota
Diseases= Black stem rust of wheat and other cereals, white pine blister rust, corn smut, loose smut of oats
Conidia
Asexual reproduction
spores produced by conidiogenous cells
occur singly or in chains
Sporangia (sporangium)
Asexual reproduction
Sac-like structure entire contents converted into 1 or many spores
Identify and explain the 3 phases of sexual reproduction for fungi.
Plasmogamy: fusion of protoplasts
Karyogamy: the fusion of nuclei
Meiosis: re-establishes haploid condition
Dikaryon
2 haploid nuclei do not fuse for some time. "2 nuclei"
Meiosis in Fungi is _______.
Zygotic: formation of zygote nucleus
Gametangium (pl: gametangia)
gamete-producing structures
*May form gametes or simply contain nuclei functioning as gametes.
Endomycorrhizae
type of mycorrhizae where the fungi penetrate the plant root cells and increase the uptake of nutrients by both plant and fungal cells.
Antheridia
multinucleate gametangia
"Male"
Ascogonia
Multinucleate gametangia
"Female"
Trichogyne
Outgrowth of the ascogonium that the male nuclei of the antheridium pass into the ascogonium
Fusion of protoplasts is called_______?
Plasmogamy
Dikaryotic means....?
Contain 2 compatible haploid nuclei
What is the difference between Hymenomycetes and Gastromycetes?
Hymenomycetes produce their basidiospores on a distinct fertile layer (hymenium) which is exposed before the spores are mature.
Gastromycetes have no distinct hymenium visible at the time the basidiospores are released
Define and explain the parts of a mushroom in class Hymenomycetes.
Pileus: Cap
stipe: stalk
volva: cup on surface of cap, at the base of stipe
gills: lower surface of the cap consists of radiating strips of tissue lined with hymenium
Peridium
Outer covering of basidiomata of Gastromycetes that varies from papery thin to thick and rubbery
Saprophytic
feeds off of dead animals
What makes the class Teliomycetes different than Basidiomycetes?
The do not form Basidiomata
Ectomycorrhizae
Fungi that do not go into the cells of roots
Increase surface area and absorption
grow in between cells creating hartig net
Hartig net
in ectomycorrhizae when the fungi grow in between the cells, this allows for a "net" to absorb nutrients to release into cells
Conidial fungi
fungi with no known sexual state, artificial group of fungi AKA fungi imperfecti
Alternation of generations
alternate between gametophitic and sporophitic generations
Name the characteristics that differentiate the phyla of Protista. (5 of them)
1. Photosynthetic pigments
2. Food (photosynthate) reserve
3. Cell Wall components
4. Presence or absence of flagella, #, and location
5. Various special features
Which phylum of Protista has the following characteristics:
1. chl a & b
2. food reserve of paramylon
3. usually 2 unequal length flagella
4. no cell wall but instead a pellicle
5. found sometimes in marine habitat but usually freshwater
Euglenophyta (Euglenoids)
Compare and contrast Cryptomonads and Euglonoids.
Similarities: require certain vitamins, pigmented photosynthetic members and phagocytic members that consume particles, no cell wall,
Differences: Cryptophyta: may have proteinaceous layer under plasma membrane, have a chloroplast endoplasmic reticulum, live in cold water (freshwater or marine)
Nucleomorph
reduced nucleus (meaning "looks like a nucleus")
remains of the nucleus of red algal cell that was ingested and enslaved for photosynthetic capabilities.
Cryptomonads
Characteristics of Rhodophyta and give an example.
Has chl a and phycobilins (found in cyanobacteria) as well as carotenoids
Floridean starch
no flagella
cellulose cell wall embedded in matrix of galactans
Marine, many found in tropical areas
Example: Bracteospermum , Coralline algae
This phylum of Protista has no photosynthetic pigment (or chl a & c, carotenoids, peridinin), uses starch as a food reserve, have no flagella except in the gametes, have a layer of vesicles beneath plasma membane with no cellulose plates, and have symbiotic relationships (freshwater and marine)
Dinophyta
Zooxanthallae is an example of the phylum ________ that has a symbiotic relationship with corals.
Dinophyta
What characteristics make phylum Myxomycota different from other phylums of Protista? Please give an example of Myxomycota.
Has more characteristics of protozoans than fungi!!!
Uses glycogen for food reserve
Has 2 flagella but only in reproductive cells
No cell wall on plasmodium
Terrestrial!!! but needs moist and shady area
Has sclerotium (encysted stage)
Example: Physarium
Compare and contrast Phylum Myxomycota and Dictyosteliomycota.
Similarites:
* Both are slime molds
* Both use glycogen for food reserve
* Both are terrestrial
Differences:
* Dictyosteliomycota: cellular slime mold that has a cellulose cell wall, closely related to ameobas, has macrocyst production, can undergo chemotaxis
* Myxomycota: plasmodial slime mold, has flagella in reproductive stages, has plasmodiocarp
Chemotaxis
process by which organisms move by chemical reactions
Identify and explain the 3 types of gametic formation.
Isogamy: gametes are produced but can't tell the difference between male and female (note there is a chemical difference)
Anisogamy: different gametes (different sizes) and female is usually larger
Oogamy: female gamete (ovum) not flagellated, male is much smaller but flagellated
Compare and contrast Dictyosteliomycota and Oomycota
Similarities
* no photosynthetic pigments
* both use glycogen as food reserve
* both have cellulose (or cellulose like material) for cell wall
Differences
* Oomycota is commonly known as water molds while Dictyosteliomycota is known as cellular slime molds
* Cellular slime mold is terrestrial, water molds are mostly aquatic (marine or fresh) although some are terrestrial
* Oomycota have 2 flagella in zoospores in males
Which Protista phylum causes downy mildew in grapes as well as blight of potato?
Oomycota
Characteristics of Bacillariophyta.
* AKA: diatoms
* have chl a & c, carotenoids, and esp fucoxanthin
* food reserve: chrysolaminarian
* no flagella, except in male gametes of centric diatoms
* silica cell wall
* found in freshwater, marine and terrestrial environments
* Basis of most aquatic food webs!!!!!
True or False: In sexual reproduction of an Oomycete, the male nuclei from the antheridia travel down the fertilization tubes of the oogonia, nuclear fusion occurs creating a zoospore.
FALSE. The thick-walled zygote formed is called an oospore which develops into a hypha, into a zoosporangium to renew the cycle.
Oomycota, Bacillarphyta, and chrysophyta are closely related by the occurrence of their ______. They are more commonly known as____________.
Flagella
heterokonts (different flagella)
In oomycetes, 1 to many eggs are produced in this structure.
oogonium (pl: oogonia)
Diatoms have a unique structure of their 2-part cell walls. What is these structures called?
Frustules
Diatoms mainly reproduce asexually. Explain how.
Cell division
Each daughter cell receives 1/2 of the frustule from parental and constructs a new half.
When does sexual reproduction in diatoms take place?
Because it takes 1/2 of parental, typically get smaller w/each generation
When it gets to a critical size!
Sometimes by changes in physical environment
When sexual reproduction in centric Diatoms does occur, it is typically _________.
oogamous
When sexual reproduction occurs in pennate diatoms, it is ___________.
Isogamous
The phylum chrysophyta are sometimes colorless, but others are a golden-brown color. This is due to what?
Fuxoxanthin (carotenoid)
Explain, in words, the life cycle of the Fucus.
Gametangia formed in conceptacles found in diploid individuals
8 eggs per oogonium and 64 sperm antheridium
Eggs and sperm released into water
fertilization takes place
meiosis= gametic
zygote grows into new diploid individual.
What photosythetic pigment does Rhodophyta have that makes them unique?
phycobilins (mask the color of chl a)
gives the algae its red appearance
Explain Chlorophyceae's unique mode of cytokinesis.
Involves phycoplast
daughter nuclei move toward one another as nonpersistent mitotic spindle collaspes
phycoplast developes parallel to plane of cell division (phycoplasts: ensure cleavage furrow will pass between 2 daughter nuclei)
Explain Charophyceae's mode of cytokinesis.
phragmoplast
microtubules in phragmoplast are oreinted perp. to plane of cell division