This ppt describes about the genus Riccia, its distribution, habiata, gametophytis as well as sporophytic phase, etc. Hope it will help the students of Botany in preparing for their examk nations.
This is a detailed presentation on Morphology, anatomy and reproduction of Marchantia spp. with high quality pics and eye capturing transitions and animations
This ppt describes about the genus Riccia, its distribution, habiata, gametophytis as well as sporophytic phase, etc. Hope it will help the students of Botany in preparing for their examk nations.
This is a detailed presentation on Morphology, anatomy and reproduction of Marchantia spp. with high quality pics and eye capturing transitions and animations
Richard's aventures in two entangled wonderlandsRichard 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.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
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.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
(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.
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
1. LIFE CYCLE OF ANTHOCEROS
DR. AVINASH K. ANEY
M.Sc., M. Phil., Ph.D. SET
Head
Department of Botany,
Science College, Pauni, Dist. Bhandara
2. Occurrence and distribution:
Cosmopolitan in habitat
Genus comprising 20 species, found in
25 species reported from India
Three common Himalayan species: A. himalyanesis, A. erectus and A. chambensis
Most commonly found in hilly regions such as Mussoorie, Kumaon hills, Chamba
valley and other places, 5000 to 8000 feet altitude
Some species are reported from South India
Classification and systematic position:
Division: Bryophyta
Class: Anthocerotopsida
Order: Anthocerotales
Family: Anthocerotaceae
Genus: Anthoceros
3. External features/External morphology:
Plant body is small, thalloid gametophyte, prostrate
Thallus dorsiventrally differentiated, and dark green in colour
Thallus lobed and lobes are somewhat divided
Mid-rib is absent
Dorsal surface is smooth and dark green
Ventral surface rough with simple, smooth-walled rhizoids
Ventral scales and tuberculate rhizoids all totally absent
Dark green colouration of the thallus is because of presence of Nostoc colonies
Nostoc colonies are seen from the underside
4. Internal structure of the thallus: (V.S. of thallus)
Anatomy of thallus is very simple
Epidermis:
Both the surfaces are covered by single layered epidermis
Upper epidermis also called dorsal epidermis and lower is called ventral epidermis
Epidermal cells compactly arranged with chloroplast
Air chambers and air pores absent
Only smooth walled simple rhizoids present on the ventral epidermis
Internal to upper and lower epidermis, simple parenchymatous cells present
The cells are large, compactly arranged and hexagonal in shape
Each cell contains a big lens shaped chloroplast with a single pyrenoid in the center
Certain intercellular cavities are present on the ventral side of thallus, called mucilage cavities
These cavities open by small openings called slime pores
Sometimes, colonies of blue-green algae, Nostoc are present in these cavities
7. 1. Vegetative reproduction:
A. By death and decay of posterior part of thallus:
The older posterior part of the thallus disintegrates due to ageing.
When this decay of cells reaches dichotomy, the lobes become separated.
Each detached lobe with growing point can develop into new plant of Anthoceros.
B. Persistent growing apices:
The thalli completely dried up during summer, leaving the growing apices
Apices tolerate the adverse condition and develops into new thalli during favorable condition
C. Formation of tubers:
In certain species, thallus becomes thickened at several places on the margins
Such marginal thickenings are called tubers
The tubers are perennating structure and can survive during adverse condition
They detached from the mother plant and during favorable condition develop into new thalli of
Anthoceros
D. By gemmae:
Gemmae are reported to found on the dorsal surface of thallus in some species
Reported in A. gladulosus, A. formosae
Each gemmae germinate to form new thalli of Anthoceros
8. 2. Asexual reproduction:
Takes place by spores produced in sporophyte
3. Sexual reproduction:
Species of Anthoceros may be homothallic (monoecious) or heterothallic (dioecious)
Sex organs are antheridia and archegonia
Sex organs develops directly on the thallus and are embedded into thallus tissue
Structure of mature antheridium:
E
Each
Antheridia are produced in cavities called anthreridial
chamber
They may be produced singly or in groups of three to four
The anthreridial cavities are covered by roof layer
Mature antheridium is stalked and club shaped
The stalk is short and multi-layered
Body of antheridium is covered with single layered jacket
Body accommodates numerous androcytes, which
metamorphoses into antherozoids
Each antherozoid (sperm) is uninucleate, rod-like, elongated structure
It has tapering anterior end and posterior broader portion called vesicle
Vesicle contains the male nuclei (n)
Two equal lengths flagella arise from the anterior narrow end
Antherozoids are chemotactic and motile structure
9. Structure of mature archegonium:
Fertilization:
Act of union of haploid male gametes (n) with haploid female gamete (n) is called
fertilization
Water is very essential for the act of fertilization
Pre-fertilization changes:
Matured antheridia opens due to water and biflagellate antherozoids liberate
Chemotactic antherozoids swim on the film of water and reaches the archegonia
Prior to fertilization, cover cells detached from archegonium and neck canal become gelatinized due
to disintegration of all NCCs and VCC
Many antherozoids enter the archegonium, travel through neck and but one lucky antherozoid
penetrate the egg and fertilization is affected to produce diploid (2n) zygote
Each
Archegonia are found embedded in the thallus
They remain in direct contact with the thallus tissue
They do not have their own jacket layer
Mature archegonium is a flask-shaped structure
Differentiated into posterior broader venter and anterior narrow neck
Venter contains basal egg (n) cell and upper venter canal cell (VCC)
Neck consist of an axial row of 4-6 neck canal cells (NCCs)
Four compactly arranged cover cells (Cap/lid cells) are present at the top
10. Post-fertilization changes:
After fertilization, zygote (2n) begins to enlarge, secrete a cellulose wall around and
begins to develop into embryo
Zygote divides first by transverse wall producing two celled embryo
Embryo divides and redivides to produce spore producing structure called
Sporogonium
External features of sporogonium (Sporophyte):
Anthoceros sporophytes are much elongated structure
Arise in the form of horny structure at the place of
fertilized archegonia
Usually 2-3 cm long, in some species, they may be 15
cm long
Because of the horny appearance of sporophyte, the
species are called ‘hornworts’
Mature sporogonium differentiated into foot,
meristematic zone and elongated, erect capsule
Place of seta is taken by meristematic zone
Lower portion of sporophyte is embedded in thallus
tissue called involucre
Capsule is indefinite in growth
11. Internal structure of sporogonium:
Anthoceros sporophytes differentiated into three regions: foot,
meristematic zone and capsule
Foot:
Foot is bulbous and embedded deeply in thallus tissue
Consist of compactly arranged cells
Absorbs water and nutrition from mother plant
Meristematic zone:
Seta is absent, instead presence of middle meristematic zone
The cells of this zone divides continuously adding the cells and
resulting in continuous increase in length of capsule
Capsule:
Main part of the sporogonium
Much elongated, erect and slender
Entire capsule is covered by four to six layered wall of parenchymatous cells
Outermost layer is epidermis, which is interrupted at several places by stomata
The cells of wall layer possesses chloroplast and is photosynthetic in function
Centre of the capsule is occupied by sterile tissue called columella
It is generally 16 cells in thickness and provides mechanical support to the capsule
Also acts as a water conducting tissue
Columella remain surrounded by sporogenous tissue
12. Sporogenous tissue is reported to be in different stages of development
Just above the meristematic zone, archesporium is young and single layered
It is two layered thick above
Above region consist of diploid mother cells (2n) and elater mother cells, tetrad of spore
(n) and the spore and elaters towards the tip region
Spores and Elaters:
Sporogenous cavity contains spores and elaters
Elaters are elongated and multicellular, called pseudoelaters
They may be branched or unbranched with cells joined by
oblique septa, hence called pseudoelaters
Hygroscopic nature helps in liberation and dispersal of spores
Twisting of pseudoelaters exert a pressure on wall of capsule
resulting in breaking the wall layer
Spores are small, somewhat spherical, unicellular, uninucleate and
haploid, ranging from 12 µ to 30 µ in diameter
Possesses two wall layers: Outer, thick, inelastic, rough, sculptured
called exine or exosporium, inner, thin, elastic and smooth called intine
or endosporium
Colour of the matured spore varies from species to species
It may be yellow, brown, dark brown or black
13. Dehiscence of capsule and dispersal of spores:
On maturation, the tip of sporogonium becomes black or brown in colour
Capsule dehiscence depends upon water
Dry atmosphere helps in dehiscence of capsule
The tip of capsule shrivels up by losing water
Dehiscence begins from the tip of capsule by the formation of longitudinal slit
The longitudinal slit widen and enlarge and proceed towards base
The spores are liberated out and dispersed through the wind
Tiny spores are easily carried out by wind current and settled on the substratum
Germination of spores:
After liberation from the capsule, the spores undergo
a period of rest for some period
The germination starts during favourable condition
Spore enlarge in size by absorption of water
Exine of the spore ruptures and intine comes out in
the form of germinal tube through germ pore
Nucleus divides to produce two celled embryo, that divides to form irregular protonema
Rhizoids comes out from lower surface and enter the soil
Finally, it develops into young gametophyte of Anthoceros
14. Life cycle and alternation of generation:
Life cycle is heteromorphic and haplodiploidy type
Consist of two phases i.e. gametophytic and sporophytic
Gametophytic phase is haploid, first, dominant and independent
Sporophytic phase is diploid, second, conspicuous and dependent on the gametophyte
Two important events takes place in life cycle i.e. fertilization and meiosis
Fertilization results in diplodization (2n)
Meiosis results in haplodization (n)
Two phases comes in alternate manner with one another, hence called alternation of generation