This is a detailed presentation on Morphology, anatomy and reproduction of Marchantia spp. with high quality pics and eye capturing transitions and animations
This is a detailed presentation on Morphology, anatomy and reproduction of Marchantia spp. with high quality pics and eye capturing transitions and animations
description of different types of reproductive organs, developmental stages and process of reproduction in Cycas. Various internet sources have been used.
description of different types of reproductive organs, developmental stages and process of reproduction in Cycas. Various internet sources have been used.
Soral & Sporangial Characters in Pteridophytes.pdfANAKHA JACOB
Sporangia are Spore bearing structure.
• May be eusporangiate or leptosporangiate.
• Homo- or Heterosporous.
• Terminal/ Lateral/ aggregated into specialized structures.
Tassel is regarded as primitive and acrostichoid condition as advanced.
The sporangia on expanded sporophyll are with or without the
indusium(protective covering).
• The sori lacking indusia are exindusiate or naked (Gleicheniaceae).
This is a Life Cycle of Shpagnum, A good content for Masters Students. (But this content is not made by me...but i thought that this will help many students who are in search for content)
Thank you 😊
It is called as “living fossil”
The whole order is extincted except one species Ginkgo biloba
This order was occurred in Triassic periods of Mesozoic age (200,000,000 years ago)
This order consists of 16 genera and many species (all in fossil forms except one)
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.
(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.
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.
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.
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.
3. SELAGINELLA
spike moss or club moss
Habitat
• About 700 species of selaginella are distributed in the tropical and
temperature areas.
• Most of the selaginella species grow in damp shady areas .
• Some species are xerophytes.
e.g : S. lepidophylla, S. rupestris
• Some are epiphytic eg: s.oregana
• Common species
S. rupestris
S. megaphylla
S. kraussiana
S. bryopteris
4. MORPHOLOGY OF SELAGINELLA
• The plant body is sporophyte and differentiated into:
Root
Stem
Leaves
Ligules
Rhizophore
5. ROOT
• The root is adventitious grow from
the tip of rhizophore or directly
from the stem.
• Root are arise endogenously and
branched dichotomously.
• Aerial root contain cap.(in epiphyte)
• Root hair is present.
6. STEM
• Stem is green, herbaceous, dichotomously
branched , erect or prostrate with erect
branches.
• Stem is covered with leaves.
• They are also pseudomonopodia ( false
growth from one point).
• The shoot apex consists of a single apical
cell in most cases.
7. LEAVES
• Leaves are microphyllous with a single unbranched midrib.
• On the upper surface a small, membranous, tongue like outgrowth called ligule is
present.
• The leaves are dorsiventral.
8. • Two types of leaf condition:
1. Homoeophyllum or
(isophyllous)
2. Heterophyllum or
(anisophyllous)
Homoeophyllum Heterophyllum
Leaves in a plant are all one kind such
condition is called is isophylly and the
leaves are called isophyllous.
Leaves of plants are two kinds:
1. Small , 2. Large
such condition is called anisophylly
and the leaves are called anisophyllous
9. LIGULE
• On the upper surface a small, membranous, tongue like or leaf like outgrowth
called ligule present on the adaxial side of the leaf.
• A mature ligule has a prominent basal portion called the glossopodium.
• Definite function of the ligule is unknown.
10. RHIZOPHORE
• It is a colourless, leafless, unbranched and cylindrical structure.
• This structure arises from the prostrate axis at the point of dichotomy and
elongates downward.
• free end of rhizophore touches the soil it develops a tuft of adventitious roots .
• Root cap is absent . It develops adventitious root at its tip.
12. STEM ANATOMY
• Epidermis is without hair and stomata. It is surrounded by a cuticle.
• Epidermis is followed by a well defined cortex region. It is parenchymatous or is
differentiated into outer sclerenchymatous and inner parenchymatous regions.
• Stele is generally protostelic, where xylem is surrounded by phloem cells. The
number of steles varies in different species.
• Central portion is separated from cortex by a cavity having air spaces
• Endodermis :the cortex and central tissue is connected by radially elongated cells
called trabeculae.
• Stele is surrounded by a pericycle that is single layered. Pith is generally absent.
13.
14. LEAF ANATOMY
• Epidermis single layered on the lower and upper side stoma is present.
• Stomata present on the upper surface .Epidermis contain chloroplast.
• Mesophyll is uniformly formed either all of spongy or all palisade like elongated
cells with air spaces
• Simple vascular bundle at the center.
15. LIGULE ANATOMY
• The ligule arise from several short rows of superficial cells.
• Fully developed ligule consists of a distinct and hemispherical basal region where
cells are large and thin walled and contain vacuolated cytoplasam this region is
glossopodium.
• Glossopodium surrounded by a sheath called glossopodium sheath.
16. ROOT ANATOMY
• Outermost layer is epidermis ( large single layer ), covered by cuticle.
• Root hairs are present and arise from some epidermal cells.
• Lower region of the epidermis, wide zone of cortex is present
1. Outer hypodermis ( have sclerenchyma cells)
2. Inner parenchyma cells.
• Endodermis layer is present ( inconspicuous )
• Single layered pericycle is present just below the endodermis.
• Xylem is surrounded by phloem
17.
18. RHIZOPHORE ANATOMY
• Outermost layer is epidermis. It is of thick walled and single layer cells.
• Root hairs are absent.
• Just below the epidermis there is cortex region
1. Hypodermis ( thick walled) few layered.
2. Thin walled parenchymatous region
• After cortex region endodermis layer around the pericycle.
• Thin walled pericycle is present around the vascular tissue.
• Stele is protostele ( xylem is in center and phloem surrounds the xylem)
21. VEGETATIVE REPRODUCTION
• Fragmentation
Under humid conditions in S. rupestris,branches of the stem develop some
roots . These branches later disjoin from the parent plant and develop into
separate individual plants.
• Tubers
These appear towards the end of the growing season. The tubers may be
aerial, developing at the tips of underground branches (e.g., S. chrysocaulos)
(e.g., S. chrysorrhizos). Under favourable conditions tubers germinate into a
new plant.
22. • Resting Buds
The resting buds develop at the tip of
some aerial branches. They pass the
unfavourable conditions and develop
rhizophore in the favourable conditions.
23. Sexual reproduction by spores
• Selaginella is a sporophytic plant and reproduce sexually.
• Selaginella is a heterosporous i.e., produce two different types of spores—
megaspores and microspores.
• These spores are produced in megasporangia and microsporangia, respectively
which, in turn, are produced on fertile leaves known as megasporophylls and
microsporophylls respectively.
• Usually both these structures are grouped together to form a compact structure
known as strobilus which is usually a terminal structure.
24. STROBILUS:
It is a reproductive structure
formed by the aggregation of ligulate
sporophylls at the apex of the
branches of stem. The length of the
strobilus varies from 1/4 inch to 2-3
inches in different species. In some
species as for e.g., S cuspidata, S.
patula etc. the growth of the stem
continues beyond the strobilus and
such condition is called selago
condition
25.
26. SPORANGIA
• Mature sporangia is a stalked structure consist short stalk and capsule.
• Stalk is multicellular and multiseriate ,
capsule is 2 layered wall called jacket.
• Two types of sporangia:
1. Megasporangia
(large and pale)
2. Microsporangia
(small , slightly elongated )
27. Development of sporangia
• Sporangium development is of the eusporangiate type. Development of
megasporangia and microsporangia similar up to formation of spore mother cell.
• Sporangia initial present in axil of the leaf. It divides to form outer jacket initial and
inner archesporial initials.
• The archesporial initial divides to form mass of sporogenous tissue. outer most layer
of sporogenous tissue forms tapetum.
• Jacket initial by further division rise to a jacket layer .
• All sporogenous cells in the microsporangium become spore mother cells. SMC
separate from each other and they under go meiosis to form microspores and several
SMC produce megasporangium.
• But only one SMC is functional rest are disintegrate. The spore mother cell divide
meiotically to produce 4 megaspore.
• The development of megaspore started before their shedding from the sporangia.
28.
29. Gametophytic generation
Spores and gametophyte
• Spore is the first cell of gametophytic generation and they are haploid and
uninucleate.
• Selaginella is heterosporous they produce two types spores :
1. Microspores it produce microsporangium:
Tetrahedral , two layered outer exine and inner intine.
Exine thick and intine thin
2. Megaspores it produce megasporangium:
Tetrahedral with triradiate ridge and spore coat is thick it may be 2or3 layered.
If it is 2 layered outer exine and inner intine.
If it is 3 layered outer exine ,middle mesospore and inner endospore.
exine layer is thick and inner intine thin.
30. GERMINATION
• Spore germination takes place by segmentation .
• Initial stage of germination is spores remain in sporangia.
• Thus, spores are shed as multicellular gametophyte.
• Microspores germinate to form :
(Male) microgametophyte
(Female) megagametophyte
31. Germination of microspore and development of
microgametophyte
• Microspore is first divides unequally .
• Resulting form small prothalli cell and large antheridial initial.
• Prothalli cell does not under go division simply become vegetative part of
prothallus.
• Antheridial cell undergo division until 12 cell formed.4 of them form a central
core and other are arranged around them.
• The central cells called primary androgonial cell and marginal cell called jacket
cells.
• In this stage microgametophyte consist 13 cells namely 4 androgonial cell,1
prothallial cell,8 jacket cell.
32. Germination of megaspore and development of
megagametophyte
• Megaspore nucleus divides many times forming a coenocytic mass of numerous
free nuclei.
• Now wall formation begins between the nuclei of the apical part and a cushion
like cellular mass is formed in the part.
• Below this tissue the gametophyte is still in the free nuclear coenocytic stage.
• Most of the superficial cells in the apical cushion become archegonial initial.
• Few archegonial initial appear in the apical region
33. FERTILIZATION
• Water is necessary to carry out the process of fertilization.
• The swimming antherozoids reach the egg through the neck of archegonium and
the nucleus of antherozoid fuses with the egg nucleus thus forming a zygotic
nucleus.
• The fertilized egg secretes a wall around it forming a diploid structure known as
zygote or oospore (2x).
• Thus the gametophytic generation ends and the initial stage of sporophytic
generation is formed.
34. Embryo Development (Young Sporophyte):
• Oospore or zygote is the initial stage of sporophytic generation.
• oospore first divides by a transverse division into an upper suspensor initial
(epibasal) and a lower embryo initial (hypobasal) .
• The suspensor initial further divides in all directions forming a multicellular
suspensor .
• The embryo initial divides by 2 vertical divisions at right angle to each other thus
forming 4 cells .
• One of these 4 cells divides by an oblique wall forming a shoot initial.
• Now the cells except the shoot initial divide sporophyte transversely forming 2
tiers of 4 cells each.