This presentation is based on the anatomy of fruit, types of fruit, their description and the reproductive part of fruit which is seed, and the anatomy of seed and the types of germination.
This presentation is based on the anatomy of fruit, types of fruit, their description and the reproductive part of fruit which is seed, and the anatomy of seed and the types of germination.
This is a general presentation on fruit types and the specific information used to distinguish them. In my class, this input was provided prior to a full-on exploration of as many different types of fruit we could get our hands on.
In a very rare move for me... images were shamelessly borrowed from all over for educational purpose.
Este trabajo fue realizado por la alumna Paulita de Carabasa de segundo año de Polimodal, a partir de los contenidos de Biology.
Gracias!!! Paula. Excelente trabajo...
This is a general presentation on fruit types and the specific information used to distinguish them. In my class, this input was provided prior to a full-on exploration of as many different types of fruit we could get our hands on.
In a very rare move for me... images were shamelessly borrowed from all over for educational purpose.
Este trabajo fue realizado por la alumna Paulita de Carabasa de segundo año de Polimodal, a partir de los contenidos de Biology.
Gracias!!! Paula. Excelente trabajo...
1. Reproduction in Lower and higher plantsBio-Geek
This ppt is for class 12th students of state board as well as CBSE board.
This presentation contain exercise of state board chapter.
it will helpful to NEET aspirants as well as for B.Sc. students also
Events of fertilization
A] Pollination brings female and male gametophyte together- The male and female gametophytes must meet and unite their gametes to fertilize egg. This is done by pollination, in which pollen is placed on the stigma of the carpel.
B] Germination of pollen grain under suitable condition- The cytoplasm of the pollen grain absorbs sugar and water from the stigma and bulges out to produce a tube known as pollen tube by braking down exine of pollen grains. This germinating pollen tube grows down through the stigma and style of flower towards the micropyle of the ovary. This tube produces chemical, calcium such as that dissolves the tissues of the style and the tip of the pollen tube enters the ovary through the micropylar end occurring double fertilization.
Pollination brings female and male gametophyte together- The male and female gametophytes must meet and unite their gametes to fertilize egg. This is done by pollination, in which pollen is placed on the stigma of the carpel.
B] Germination of pollen grain under suitable condition- The cytoplasm of the pollen grain absorbs sugar and water from the stigma and bulges out to produce a tube known as pollen tube by braking down exine of pollen grains. This germinating pollen tube grows down through the stigma and style of flower towards the micropyle of the ovary. This tube produces chemical, calcium such as that dissolves the tissues of the style and the tip of the pollen tube enters the ovary through the micropylar end occurring double fertilization.
This slide will cover whole topic about Bryophtes and Pteridophytes. In this slide we cover about bryophytes types.Like liverworts, Mosses and Hornworts.
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.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
(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.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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 .
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.
5. Male Reproductive Part of a flower
Stamen
Anther [Bilobed] – It has
two theca hence called
dithecous
Filament
T.S. of anther – Tetragonal in shape
Microsporangia – They are four in number.
They develop into pollen Sac.
6. Structure of Microsporangium : Circular in shape
Protection
Dehiscence of anther [helps
in opening of anther to
release pollen grains]
Nourishment to pollen grains]
It has dense cytoplasm and is
binucleated
7. Microsporogenesis
Process of formation of microspore in pollen
grains from MMC
Every cell of sporogenous tissue is MMC
(Microspore Mother Cell)
Pollen Grain / Microspore / Male Gametophyte
(Spherical in shape)
8. Exine
Made up of sporopollenin
Resistant to organic material
Can withstand high temperature, strong acid
and alkali. Hence can be preserved as fossil.
Intine
Continuous inner layer
Made up of cellulose and pectin
Vegetative cell
Bigger, abundant food reserve and irregular
shaped nucleus.
Generative Cell
Small, dense cytoplasm and spindle shaped
nucleus
9. In 60% of angiosperms, pollen grains are shed
at this stage (2-celled stage) and in remaining,
generative cell divides mitotically to give rise to
2 male gametes (3-celled stage)
3-celled stage 2-celled stage
Vegetative cell Vegetative cell
2 Male Gametes Generative Cell
10. Female Reproductive Part of a flower
Gynoecium
Monocarpellary (single pistil)
Multi carpellary (More than one pistil)
Pistil is fusedSyncarpous
Pistil is freeApocarpous
11. Pistil
Landing platform for pollen
grain
Elongated slender part
Basal bulged part
Inside ovary we have ovarian
cavity (locule)
14. Pollination
Autogamy Geitonogamy Xenogamy
Pollination – Transfer of pollen grains from anther to
stigma of a pistil
Transfer of pollen grains
from anther to stigma of
a same flower
eg. pea
Transfer of pollen grains
from anther to stigma of
another flower of same
plant eg. cucurbita
Transfer of pollen grains
from anther to stigma of
another flower of different
plant eg. papaya
17. Adaptation for wind pollination
Pollen grains are light & non-sticky
Well exposed stamens & feathery
stigma
Flowers packed into inflorescence.
eg. Corn cob-tassels (stigma & style)
Adaptation for water pollination
Common in algae, bryophytes,
pteridophytes & monocots
Vallisneria, Hydrilla (fresh water)
and sea grasses like zostera
(marine)
Exception : water hyacinth & water
lily pollinated by insect or wind
Pollen grains are long ribbon like
and have mucilaginous covering
18. Adaptation for insect pollination
Flowers large, sticky and brightly coloured
Have honey and nectar which act as floral
rewards
Tallest flower of Amorphophallus provide safe
place (floral reward) for laying eggs.
Moth & Yucca – Moth deposits its egg and
Yucca in turn gets pollinated
19. Outbreeding devices
Stops inbreeding depression due
to self pollination
No synchrony between pollen
release and stigma receptivity
Anther and stigma placed at
different positions
Self incompatibility
Production of unisexual flowers
Monoecious plants (Male &
Female flowers on same plant)
prevent autogamy but not
geitonogamy
Dioecious plants prevents both
autogamy and geitonogamy
20. Pollen-Pistil Interaction
Events from pollen deposition on the stigma until
entry of pollen tube into ovule.
Dynamic process, incompatible pollens don’t grow
Compatible pollens develop pollen tubes which
grows through stigma & style to reach the ovary. It
enters the ovule through micropyle and reaches the
synergids guided by filiform apparatus.
21. Artificial Hybridization
Helps to obtain desirable characters.
Emasculation – Anthers are removed using forceps
Bagging – Flower is covered with paper bag
Re-bagging – Pollen grains dusted on stigma and
the flower covered again
Double Fertilization
Syngamy Triple Fusion
Male gametes fuses with
egg nucleus to form zygote
Other male gametes fuses
with polar nuclei to form
Primary Endosperm Nucleus(PEN)
22. Double Fertilization
Syngamy Triple Fusion
Male gametes fuses with
egg nucleus to form zygote
Other male gametes fuses
with polar nuclei to form
Primary Endosperm Nucleus(PEN)
24. Endosperm
Endosperm development precedes embryo development.
Primary Endosperm Cell (PEC) formed as a result of triple fusion
undergoes repeated divisions and a triploid endosperm tissue is formed.
In most of the cases, the PEN undergoes successive nuclear divisions
without cytokinesis, to give rise to free nuclear endosperm.
Subsequently, cell wall formation starts from the periphery and the
endosperm becomes completely cellular, e.g., coconut, rice, maize,
sunflower, etc.
Filled with reserve food materials used for nutrition of developing embryo.
The endosperm may be completely utilised by the developing embryo
before the maturation of seeds as in pea, bean and mustard, etc.
26. Embryo : Development (Embryogeny)
Develops at micropylar end of the embryo sac where zygote is situated.
Zygote Proembryo mature embryo (globular, heart-shaped).
27. Seed (fertilised ovule)
It is the final product of sexual reproduction
Consists of seed coat, cotyledons and an embryonal
axis
Perisperm: Residual, persistent nucellus. Ex. Black
pepper and Beet
Integuments of ovules harden to form the seed coat.
Micropyle facilitates the entry of oxygen and waer
into the seed
As the seed matures the embryo enters into a state of
dormancy.
28. Fruit (Develops from ovary)
Wall of the ovary develops into wall of fruit called
pericarp.
Consists of seed coat, cotyledons and an embryonal
axis
Fruits may be fleshy ex. Guava, mango
Fruits may be dry ex. Groundnut and mustard
FRUITS
TRUE FALSE PARTHENOCARPIC
29. Advantages of seeds
Seed formation is more dependable as fertilization and
pollination does not require water.
Better adaptive strategies for dispersal
Have sufficient food reserves.
Hard seed coat provides protection to the young
embryo.
Generates new genetic combination leading to
variation.
Can be stored as food.
30. APOMIXIS
Apomixis is a mode of reproduction which does
not involve formation of zygote through gametic
fusion.
Is mechanism of seed production without involving
the process of meiosis and syngamy.
It plays an important role in hybrid seed
production.
POLYEMBRYONY
The phenomenon of the development of more than
one embryo in one ovule, seed or fertilized ovum is
called polyembryony.
Caused due to fertilization of one or more than one
embryonic sac or due to the origination of embryos
outside of the embryonic sac.
