Bajrang Bali presented on the absorption of water by plants. Water is absorbed through the root hairs located in the root hair zone and transported throughout the plant. Water can be absorbed actively, using energy from respiration, or passively through transpiration pull. Active absorption involves osmotic forces or can be non-osmotic, while passive absorption relies solely on transpiration. Factors like soil water availability, temperature, aeration, transpiration rate, and root morphology affect the absorption of water. Aquaporin proteins in cell membranes aid the transport of water molecules across plant cells.
intro-hostory and discovery-characteristics of phytochrome-chemical nature of phytochrome-mode of action-mechanism-phytochrome mediated physiological responses-phytochrome is a pigment system:some evidences-role of phytochrome
Everything about photoperiodism from scratch to smart, from the oldest models to the latest models as well as proposed one, exclusive and elusive illustrations and models for proper understanding
intro-hostory and discovery-characteristics of phytochrome-chemical nature of phytochrome-mode of action-mechanism-phytochrome mediated physiological responses-phytochrome is a pigment system:some evidences-role of phytochrome
Everything about photoperiodism from scratch to smart, from the oldest models to the latest models as well as proposed one, exclusive and elusive illustrations and models for proper understanding
The soil-plant-atmosphere continuum (SPAC) is the pathway for water moving from soil through plants to the atmosphere.
Continuum in the description highlights the continuous nature of water connection through the pathway.
The low water potential of the atmosphere, and relatively higher (i.e. less negative) water potential inside leaves, leads to a diffusion gradient across the stomatal pores of leaves, drawing water out of the leaves as vapour.
Students able to understand that who helps to transport in plants, Mechanism of transport in plants, physical forces involved in transport, Behavior with different solutions.
The soil-plant-atmosphere continuum (SPAC) is the pathway for water moving from soil through plants to the atmosphere.
Continuum in the description highlights the continuous nature of water connection through the pathway.
The low water potential of the atmosphere, and relatively higher (i.e. less negative) water potential inside leaves, leads to a diffusion gradient across the stomatal pores of leaves, drawing water out of the leaves as vapour.
Students able to understand that who helps to transport in plants, Mechanism of transport in plants, physical forces involved in transport, Behavior with different solutions.
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.
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.
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.
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.
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.
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 .
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
1. PRESENTATION ON
TOPIC : ABSORPTION OF WATER
PRESENTED BY
BAJRANG BALI
Dept. of Vegetable Science
M.Sc. Previous Year.
2. ABSORPTION OF WATER
Uptake of water by plant is called
absorption of water.
• Plant absorb water from the soil
through the root hairs.
• Water is said to be the liquid gold
of life.
• Plant are capable of absorbing
water from soil solution.
• Mainly absorb capillary water.
• Plant also absorb dissolved
nutrients along with water.
3. Site of Water Absorption
Water is mainly absorption
of root hairs.
Located in a group just
above the root cap.
This area rich in root hairs
is called root hair zone.
4. Typical Root Hair
• Billions of root hairs in the
root system of a plant.
• Root hairs are tubular hair
like projections of the
epidermal cells.
• Each root hair is single cell.
• Root hairs are 0.5 to 1.0 cm in
length and 10 mue in
diameter.
5. • Root hair is modified epidermal cell
• The wall of the root is permeable to
water it is made up of cellulose and
pectic substances which are strongly
hydrophilic (water loving in nature)
• Next cell wall there is plasma
membrane enclosing cytoplasm,
nucleus and vacuole.
• Vacuole is filled with cell sap whose
water potential is more negative than
the soil solution.
6. PATH OF ABSORBED WATER
It move into the cortical cells.
After crossing the cortical cells the reaches the epidermis.
The endodermal cells lying opposite to root hairs are especially modified to transport
the absorbed water. These endodermal cells are called passage cells. The passage cells
are permeable to water because they lake of casparian thickening in their wall.
Other indodermal cells are provided with casparian thickening are impermeable to
water.
The water passege cells pass into the pericycle cells. from the pericycle cells ,the
water passage into xylem. through the xylem tube ,the water move up through stem to
reach the leaves.
The water movement from one cell to another is brought about by turgor pressure.
7. Absorption of Water
The soil water molecules are absorbed into the cell wall of root
hair cells by imbibitions.
The protoplast of root hair cell is hypertonic and the soil is
hypotonic and the soil water is hypotonic.
OP of the cell sap of root hair cell is higher than the OP of the soil
water.
OP of cell sap is usually between 3 to 8 atmosphere while that of
reach watered soil is less than 1 atm.
As the root hair cell contains less water it has less turgor pressure.
High OP and less TP of root hair cell result in increased diffusion
pressure deficit.
This leads to the increase in the suction pressure of root hairs.
The cell of endodermis facing xylem are thin walled and lack
casparian thickening. they are called passage cells.
Proposed by Atkins (1916), PRIESTLY and Arnold(1952) ANDERSON and house(1967), Levitte
(1969)
8. Mechanism of water absorption
Kramer (1949) proposed that water is absorbed by to mechanism.
9. 1.Active absorption
• Active osmotic absorption.
• Active non osmotic absorption.
Active absorption – the absorption of water by the plant
with the use of energy is known as active absorption. in
this process, the root cell play active role in the absorption
of water.
Intake of water by the plants with the use of energy is
called active absorption.
The water is absorbed by the activity of root hair cells.
The water is absorbed by the operation of osmotic forces
by the use of energy.
In osmotic active absorption, the water move from
hypotonic solution to hypertonic solution.
Proposed by Atkins (1916) &
Priestly (1922)
10. I. Active Osmotic Absorption
• The intake of water by the root hairs by the operation
of osmotic forces is called osmotic active absorption.
• Water is absorbed by the activity of root cells.
• Osmotic pressure, root pressure, turgor pressure and
DPD play the main role.
• The water move from hypotonic solution to hypertonic
solution.
• The root hair cells suck the soil water and the xylem
vessel pumps the water upwards.
11. Active non osmotic absorption of water
• This intake of water without the involvement of osmotic forces
and with the use of energy is called non osmotic active absorption.
• The water moves against concentration gradient.
• Respiratory energy is used.
• It is correlated with respiration.
• The water molecules move through symplast pathway
transmembrane pathway.
• Plant hormone like auxins stimulate non osmotic active
absorption.
Poisons retard this absorption.This concept was proposed by Kramer(1959).
12. Passive absorption
• The intake of water by plants due to transpiration pull is called passive
absorption.
• The water is absorbed due to transpiration activity in the top of the
plants.
• The root hair cell has no role in absorption. It function as an absorptive
surface.
• Water is absorbed through roots.
• Transpiration increase the concentration of cell sap and DPD in the
leaves.
• As result water from the xylem vessels move into the mesophyll cells of
leaves.
• The water in the xylem vessels is in the from of a column.
• Hence there is pulling up of water column.
• This result in a tension in the root hair cells.
• The water moves through apoplastic pathway, symplast pathway and
transmembrane pathway.
• It is now largely greatest amount of water is pulled up by passive
absorption.
13. Difference between active and passive absorption
s.no. Active absorption Passive absorption
1 Energy is required. Energy is not required.
2 The forces are created by osmotic
concentration.
Created by transpiration pull
3 Absorption is due to activity of
root hair cell.
Absorption is due to the activity of the
leaves.
4 root hair cells have high
DPD,compared to soil solution.
The mesophyll cell have high DPD
compared to xylem vessels.
5 Rate of absorption depend on
DPD.
Rate of absorption depend on transpiration.
6 Absorbed through symplast
pathway and transmembrane
pathway.
Water passes through apoplast
pathway,symplast pathway and
transmembrane pathway.
7 It is correlated with respiration
for energy.
It is correlated with transpiration.
8 The rate of absorbtion is slow. The rate of absorbtion is high.
14. Apoplast and Symplast
The water move through apoplastic
pathway(Through intercellular pathway).
Symplast pathway through plasmadesmata.
Transmembrane pathway through aquaporins.
15. Factors affecting water absorption
1. External factors:
i. Available soil water:- Dry soil decreases the rate of absorption.
Decreases in soil water reduces the rate of absorption.
ii. Concentration of solution: Soil much more concentration than the
cell sap OP high of cell sap of root cells.
iii. Soil temperature: Max. absorption of water 20ᵒC to 30ᵒC.
If temperature ↑ absorption↓.
If 20ᵒC↓ together absorption ↓.
If 0ᵒC physiologically dry.
iv. Soil aeration: Oxygen is essential for water absorption by roots.
In water logged soils, aeration is very poor and this poor aeration decreases
the permeability of root cells to water.
They are not good absorption of water. Therefore, such water logged soils
are to be physiologically dry.
16. Internal factors
i. Transpiration:
Rate of absorption of water is directly proportional to that of
transpiration.
High rate of transpiration increase the rate of absorption due to
transpiration pull transmitted to roots.
Transpiration creates a favorable condition for the entrance of water
into roots.
ii. Root hairs:
The efficiency of water absorption depends upon the characteristics
of the absorbing system(root system).
The presence of more number of root hairs accounts for the high rate
of absorption.
iii. Metabolism:
The metabolism and absorption are closely related.
The factors inhibiting the rate of respiration such as poor aeration
and KCN reduce the water absorption rate.
17. AQUAPORINS
Aquaporins are water trarnsport channels present in cell membranes. In fact, they are
integral membrane proteins, Which have central pore and a gate, embeded in the lipid
bilayer of the cell membranes.
Aquaporins act as the plumbing system for the selective transport of water molecules
into and out of the cell membrane.
Nearly, 3 billion of water molecules can pass through an aquaporin per second.
Peter Agre in 2003 indentified the integral protein that acts as a water channel and
named it aquaporin. For this discovery, he was awarded the Nobel Prize for 2003.
It is the indirect evidence for high rate of water movement across the cell membrane of
plants.