Fungi have a variety of body forms ranging from unicellular yeasts to multicellular mushrooms. They obtain nutrients by absorbing organic molecules and break down dead material as decomposers. Fungi reproduce both sexually through spores or asexually through budding. Major fungal groups are classified based on their reproductive structures. Fungi play important ecological roles in symbiosis, disease, and nutrient cycling.
Disease management system that in the context of associated environment and population dynamics of microorganisms, utilizes all suitable techniques and methods in a manner as compatible as possible and maintains the disease below economic level”.
Title
Introduction
Objectives
Justification
Methodology
Results and Discussion
Conclusion
References
Pteridophyta or Pteridophytes are Vascular Plants (also known as "seedless plants") that reproduce and disperse via spores. They do not produce either seeds or flowers.
Additional info:
+ Division Equisetophyta (horsetails & scouring rushes)
+ Division Psilotophyta (whisk ferns)
(This is our report in Botany 2.)
Made by: Sharmine Ballesteros (BS Biology 2A2-1)
Pollination, transfer of pollen grains from the stamens, the flower parts that produce them, to the ovule-bearing organs or to the ovules (seed precursors) themselves. In plants such as conifers and cycads, in which the ovules are exposed, the pollen is simply caught in a drop of fluid secreted by the ovule. In flowering plants, however, the ovules are contained within a hollow organ called the pistil, and the pollen is deposited on the pistil’s receptive surface, the stigma. There the pollen germinates and gives rise to a pollen tube, which grows down through the pistil toward one of the ovules in its base. In an act of double fertilization, one of the two sperm cells within the pollen tube fuses with the egg cell of the ovule, making possible the development of an embryo, and the other cell combines with the two subsidiary sexual nuclei of the ovule, which initiates formation of a reserve food tissue, the endosperm. The growing ovule then transforms itself into a seed.
It discuss about root system, monocot and dicot differences, functions of root system, T.S. Of dicot root system, cross section of dicot root system, parts - epidermis, root hair, cortex, parencyma, endodermis, pericycle, vascular bundles - xylem, phloem, pith difference between monocot and dicot root
9 November 1877 – 21 April 1938) was a South Asian Muslim writer,[1][2] philosopher,[3] scholar and politician,[4] whose poetry in the Urdu language is considered among the greatest of the twentieth century,[5][6][7][8] and whose vision of a cultural and political ideal for the Muslims of British Raj[9] was to animate the impulse for Pakistan.[1][10] He is commonly referred to by the honorific Allama[11] (from Persian: علامہ, romanized: ʿallāma, lit. 'very knowing, most
Mycology is the branch of biology concerned with the study of fungi.
The word 'myco' is derived from the Greek word mýkēs meaning “mushroom, fungus”.
Heinrich Anton de Bary is the father of Mycology.
Fungi are eukaryotic organisms that include such as yeasts, moulds and mushrooms. These organisms are classified under kingdom fungi.
Fungi are diverse and widespread.
Disease management system that in the context of associated environment and population dynamics of microorganisms, utilizes all suitable techniques and methods in a manner as compatible as possible and maintains the disease below economic level”.
Title
Introduction
Objectives
Justification
Methodology
Results and Discussion
Conclusion
References
Pteridophyta or Pteridophytes are Vascular Plants (also known as "seedless plants") that reproduce and disperse via spores. They do not produce either seeds or flowers.
Additional info:
+ Division Equisetophyta (horsetails & scouring rushes)
+ Division Psilotophyta (whisk ferns)
(This is our report in Botany 2.)
Made by: Sharmine Ballesteros (BS Biology 2A2-1)
Pollination, transfer of pollen grains from the stamens, the flower parts that produce them, to the ovule-bearing organs or to the ovules (seed precursors) themselves. In plants such as conifers and cycads, in which the ovules are exposed, the pollen is simply caught in a drop of fluid secreted by the ovule. In flowering plants, however, the ovules are contained within a hollow organ called the pistil, and the pollen is deposited on the pistil’s receptive surface, the stigma. There the pollen germinates and gives rise to a pollen tube, which grows down through the pistil toward one of the ovules in its base. In an act of double fertilization, one of the two sperm cells within the pollen tube fuses with the egg cell of the ovule, making possible the development of an embryo, and the other cell combines with the two subsidiary sexual nuclei of the ovule, which initiates formation of a reserve food tissue, the endosperm. The growing ovule then transforms itself into a seed.
It discuss about root system, monocot and dicot differences, functions of root system, T.S. Of dicot root system, cross section of dicot root system, parts - epidermis, root hair, cortex, parencyma, endodermis, pericycle, vascular bundles - xylem, phloem, pith difference between monocot and dicot root
9 November 1877 – 21 April 1938) was a South Asian Muslim writer,[1][2] philosopher,[3] scholar and politician,[4] whose poetry in the Urdu language is considered among the greatest of the twentieth century,[5][6][7][8] and whose vision of a cultural and political ideal for the Muslims of British Raj[9] was to animate the impulse for Pakistan.[1][10] He is commonly referred to by the honorific Allama[11] (from Persian: علامہ, romanized: ʿallāma, lit. 'very knowing, most
Mycology is the branch of biology concerned with the study of fungi.
The word 'myco' is derived from the Greek word mýkēs meaning “mushroom, fungus”.
Heinrich Anton de Bary is the father of Mycology.
Fungi are eukaryotic organisms that include such as yeasts, moulds and mushrooms. These organisms are classified under kingdom fungi.
Fungi are diverse and widespread.
Fungi is most abundantly found organism in earth, almost all parts of earth we found earth, here we represent some characteristic with their uses and disadvantages .
Fungi are eukaryotic organisms that include microorganisms such as yeasts, moulds and mushrooms. These organisms are classified under kingdom fungi.
General Characteristic of Fungi
Mycology
DEFINITION
Occurrence
Characteristics
Nutrition
Cell structure of Fungi
Fungi as parasites & pathogens
Presentation
BEST OF LUCK
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...
Intro to fungi_presentation
1. Kingdom FungiKingdom Fungi
• The characteristicsThe characteristics
of fungiof fungi
• The evolution ofThe evolution of
the fungithe fungi
• FungalFungal
classificationclassification
• Fungal life cyclesFungal life cycles
2. The Characteristics of FungiThe Characteristics of Fungi
• Body form
* unicellular
* filamentous (tube-like
strands called hypha
(singular) or hyphae
(plural)
* mycelium = aggregate
of hyphae
* sclerotium = hardened
mass of mycelium that
generally serves as an
overwintering stage.
* multicellular, such as
mycelial cords,
rhizomorphs, and fruit
bodies (mushrooms)
4. The Characteristics of FungiThe Characteristics of Fungi
• Heterotrophy - 'other food'
* Saprophytes or saprobes - feed on dead
tissues or organic waste (decomposers)
* Symbionts - mutually beneficial
relationship between a fungus and
another organism
* Parasites - feeding on living tissue of a
host.
• Parasites that cause disease are called
pathogens.
5. Heterotrophic by AbsorptionHeterotrophic by Absorption
• Fungi get carbon from organic sources
• Hyphal tips release enzymes
• Enzymatic breakdown of substrate
• Products diffuse back into hyphae
Product diffuses back
into hypha and is used
Nucleus hangs back
and “directs”
6. HyphaeHyphae
• Tubular
• Hard wall of chitin
• Crosswalls may
form compartments
(± cells)
• Multinucleate
• Grow at tips
7. Hyphal growthHyphal growth
• Hyphae grow from their tips
• Mycelium = extensive, feeding web of hyphae
• Mycelia are the ecologically active bodies of
fungi
This wall is rigid Only the tip wall is plastic and stretches
13. LichensLichens
• “Mutualism” between
* Fungus – structure
* Alga or cyanobacterium –
provides food
• Three main types of lichens:
* Crustose lichens form flat
crusty plates.
* Foliose lichens are leafy in
appearance, although lobed or
branched structures are not true
leaves.
* Fruticose lichens are even more
finely branched and may hang
down like beards from branches
or grow up from the ground like
tiny shrubs.
14. Lichen internal structureLichen internal structure
Lobaria
Lichens are nature’s biological monitorsLichens are nature’s biological monitors
of pollution and air qualityof pollution and air quality
•Thalli act like sponges
•Some species more sensitive to
pollution
•Which species are present can
indicate air quality
•Most resistant species can also be
analyzed for pollutants, including
bioaccumulation of heavy metals and
radioactive isotopes
16. Fungi are Spore-ific!!!Fungi are Spore-ific!!!
• Spores - asexual (product of
mitosis) or sexual (product of
meiosis) in origin.
• Purpose of Spores
* Allows the fungus to move
to new food source.
* Resistant stage - allows
fungus to survive periods of
adversity.
* Means of introducing new
genetic combinations into a
population
17. Reproduce by sporesReproduce by spores
• Spores are reproductive cells
* Sexual (meiotic in origin)
* Asexual (mitotic in origin)
• Formed:
* Directly on hyphae
* Inside sporangia
* Fruiting bodies
Amanita fruiting body
Pilobolus sporangia
Penicillium hyphae
with conidia
18. Hyphal growth from sporeHyphal growth from spore
mycelium
germinating
spore
• Mycelia have a huge surface area
19. The Characteristics of FungiThe Characteristics of Fungi
• Fungus is often hidden from view. It grows
through its food source (substratum),
excretes extracellular digestive enzymes,
and absorbs dissolved food.
• Indeterminate clonal growth.
• Vegetative phase of fungus is generally
sedentary.
20. The Characteristics of FungiThe Characteristics of Fungi
• Cell wall present, composed of cellulose and/or chitin.
• Food storage - generally in the form of lipids and glycogen.
• Eukaryotes - true nucleus and other organelles present.
• All fungi require water and oxygen (no obligate anaerobes).
• Fungi grow in almost every habitat imaginable, as long as there
is some type of organic matter present and the environment is
not too extreme.
• Diverse group, number of described species is somewhere
between 69,000 to 100,000 (estimated 1.5 million species total).
24. Chytridiomycota – “chytrids”Chytridiomycota – “chytrids”
• Simple fungi
• Produce motile spores -
zoospores
• Mostly saprobes and
parasites in aquatic habitats
• Could just as well be
Protists Chytridium growing on spores
Chytriomyces growing on pine pollen
25. Zygomycota – “zygote fungi”Zygomycota – “zygote fungi”
• Sexual Reproduction -
zygosporangia
• Asexual reprod. – common
(sporangia – bags of asexual
spores)
• Hyphae have no cross walls
• Grow rapidly
• Decomposers, pathogens, and
some form mycorrhizal
associations with plants
Rhizopus on strawberries
Rhinocerebral zygomycosis
26. Life cycle of Rhizopus
Asexual sporangium
with spores inside
Sexual zygsporangium
with one zygospore
27. Ascomycota – “sac fungi”Ascomycota – “sac fungi”
• Sexual Reproduction – asci
(sing. = ascus)
• Asex. Reprod. – common
• Cup fungi, morels, truffles
• Important plant parasites &
saprobes
• Yeast - Saccharomyces
• Decomposers, pathogens,
and found in most lichens
A cluster of asci with spores inside
29. Basidiomycota – “club fungi”Basidiomycota – “club fungi”
• Sexual Reproduction – basidia
• Asexual reprod – not so
common
• Long-lived dikaryotic mycelia
• Rusts & smuts –plant parasites
• Mushrooms, polypores,
puffballs, boletes, bird’s nest
fungi
• Enzymes decompose wood,
leaves, and other organic
materials
• Decomposers, pathogens, and
some form mycorrhizal
associations with plants SEM of basidia and spores
30. MushroomMushroom
Life CycleLife Cycle
Nuclear
fusion in
basidium
Meiosis
Hyphal fusion
of haploid
mycelia
haploid
mycelium
young basidia - the
only diploid cells
mycelium and fruiting
body are dikaryotic
N 2N N+N
32. Some fungi have more thanSome fungi have more than
one scientific name – Why?one scientific name – Why?
• Teleomorph: the sexual reproductive stage
(morph), typically a fruiting body (e.g., Morchella
esculenta, Agaricus brunescens).
• Anamorph: an asexual reproductive stage
(morph), often mold-like (e.g. Aspergillus flavus,
Fusarium solani). When a single fungus produces
multiple morphologically distinct anamorphs, they
are called synanamorphs.
• Holomorph: the whole fungus, including all
anamorphs and the teleomorph.
33. Deuteromycota – Form PhylumDeuteromycota – Form Phylum
“Imperfect Fungi”“Imperfect Fungi”
• Fungi that seldom or never reproduce
sexually.
• Asexual reproduction by vegetative growth
and production of asexual spores common.
34. YeastsYeasts
• Single celled fungi
• Adapted to liquids
* Plant saps
* Water films
* Moist animal tissues
Candida
Saccharomyces
35. MoldsMolds
• Rapidly growth
• Asexual spores
• Many human importances
* Food spoilage
* Food products
* Antibiotics, etc.
Fig 31.21 Antibiotic activity
Noble Rot - Botrytis
36. HUMAN-FUNGUS INTERACTIONSHUMAN-FUNGUS INTERACTIONS
• Beneficial Effects of Fungi
* Decomposition - nutrient and carbon recycling.
* Biosynthetic factories. Can be used to produce drugs, antibiotics,
alcohol, acids, food (e.g., fermented products, mushrooms).
* Model organisms for biochemical and genetic studies.
• Harmful Effects of Fungi
* Destruction of food, lumber, paper, and cloth.
* Animal and human diseases, including allergies.
* Toxins produced by poisonous mushrooms and within food (e.g.,
grain, cheese, etc.).
* Plant diseases.
Editor's Notes
Most enzyme release (and absorption) at tips
Proteins and other materials synthesized by the entire mycelium are channeled by cytoplasmic streaming to the tips of the extending hyphae.
Chitin is the same material used by Arthropods (Insects, crabs, etc.) in their exoskeletonsa
Nuclei of fungi are hard to see without stains
Half of the mushroom-forming fungi (basidiomycota) form mycorrhizas with trees
Some people think that the spongy tissue in roots evolved as a place where fungi could invade to form early links with plants that helped them survive the harsh life on early earth
4 of the regions where mycorrhizas are found are circled.
These are “ecto” because the hyphae remain outside the root cells (though they extend inside the root)
Thallus is a plant-like body that doesn’t have roots, stems or leaves
Thallus doesn’t look like either partner
Dual nature of thalli was not fully understood until early 1900’s
Fungus gives the name to the lichen (by agreement)
Fungus usually, but not always, an Ascomycote (in 8+ independent orders)
Algae green. If bluegreen bacteria present, lichens fix nitrogen (turn atmospheric nitrogen into amino acid nitrogen in proteins)
The nature of lichen symbiosis is may also be described as mutual exploitation instead of mutual benefit.
Lichens live in environments where neither fungi nor algae could live alone.
While the fungi do not not grow alone in the wild, some (but not all) lichen algae occur as free-living organisms.
If cultured separately, the fungi do not produce lichen compounds and the algae do not “leak” carbohydrate from their cells.
In some lichens, the fungus invades algal cells with haustoria and kills some of them, but not as fast as the algae replenish its numbers by reproduction.
Lobaria oregana prefers old-growth conifer canopies in forests with clean air.
Fungi reproduce by releasing spores that are produced either sexually or asexually.
The output of spores from one reproductive structure is enormous, with the number reaching into the trillions.
Dispersed widely by wind or water, spores germinate to produce mycelia if they land in a moist place where there is food.
Fungal mycelia can be huge, but they usually escape notice because they are subterranean.
One giant individual of Armillaria ostoyae in Oregon is 3.4 miles in diameter and covers 2,200 acres of forest,
It is at least 2,400 years old, and weighs hundreds of tons.
(Actually noone has seen this of this extent – but cultures have been taken from soil over that area and all isolates have been found to be the same individual)
Ten cubic centimeters of rich organic soil may have fungal hyphae with a surface area of over 300 cm2
Molecular studies indicate that animals, not plants, are the closest relatives of fungi.
Both Animals and Fungi are related most closely to a group of Protists known as the choanoflagellates (collar flagellates)
Kingdom began in ocean during Precambrian (Late Proterozoic era)
More than 100,000 species of fungi are known and mycologists estimate that there are actually about 1.5 million species worldwide.
The phyla of fungi are determined by
1. motility of spores
2. nature of sexual stage
Fungi moved onto land with the plants in the Early Paleozoic
Much of the evolution of fungi was in conjunction with the evolution of plants and plant parts
For example, when roots evolved, fungi were there and helped (mycorrhizas)
When wood evolved, fungi evolved to take advantage of it
Other evolutionary changes related to animals
Classified in CMR as true fungi (because of their molecular relationships)
Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)
Most of the 600 zygomycote, or zygote fungi, are terrestrial, living in soil or on decaying plant and animal material.
Asexual reproduction in sporangia
One zygomycote group form mycorrhizas, mutualistic associations with the roots of plants.
Mycologists have described over 60,000 species of ascomycetes, or sac fungi.
Ascomycota tend to grow from spore to spore in one year and relate well to living plant tissues
There is diverse form in the growth and fruiting structures – yeasts to morels, many intermediate (and small)
Asexual reproduction by conidia (externally produced, not in sporangia)
Half of the Ascomycota form lichens (evolved 8 or more times in different orders) but not all lichens are Ascomycotes
This begins the first of several photographic reviews of fungal diversity. Enjoy the pictures and try and get a feeling of some of the different forms these fungi take and their roles in the environment.
Asexual spores conidia
Ecologically important on wood as decomposers and parasites
Half the mushrooms form mycorrhizas
Bread and wine yeast, the budding yeast, Saccharomyces
Easily cultured. For a time, this was the most important organism for studying the molecular genetics of eukaryotes
Thus, Saccharomyces is arguably the most important organism known to humans
Candida causes diseases of humans, usually experiencing chemical imbalance or immune problems
A mold is a rapidly growing, asexually reproducing fungus.
The mycelia of these fungi grow as saprobes or parasites on a variety of substrates.
Also used in foods (Blue cheese, Tempeh) and in industrial production of drugs
Early in life, a mold, a term that applies properly only to the asexual stage, produces asexual spores.
Later, the same fungus may reproduce sexually, producing zygosporangia, ascocarps, or basidiocarps
Some molds go through a “fake sex” process