The Earth’s atmosphere is divided into several layers. The lowest region, the troposphere, extends from the Earth’s surface up to about 10 kilometres (km) in altitude. Virtually all human activities occur in the troposphere. Mt. Everest, the tallest mountain on the planet, is only about 9 km high. The next layer, the stratosphere, continues from 10 km to about 50 km. Most commercial airline traffic occurs in the lower part of the stratosphere. For nearly a billion years, ozone molecules in the atmosphere have protected life on Earth from the effects of ultraviolet rays. It is a form of oxygen (O2). We all know that, oxygen we need to live and breathe. Normal oxygen consists of two oxygen atoms. Ozone, however, consists of three oxygen atoms and has the chemical formula O3.
is essential for life on Earth.
It helps plants to grow, and provides warm and light.
Sunlight also helps people to be happy and healthy
produces light and warmth but also Ultraviolet (UV) radiation. UV radiation cannot be seen or felt.
It is UV radiation, not the warmth or brightness of the sun that causes changes to skin color, damage to eyes, and other bad health effects.
what is climate change...
Direct and indirect effects of climate change on plant processes:
Phenology,
Net carbon assimilation,
Water relation,
Grain development and quality,
Nutrient acquisition and yield
is essential for life on Earth.
It helps plants to grow, and provides warm and light.
Sunlight also helps people to be happy and healthy
produces light and warmth but also Ultraviolet (UV) radiation. UV radiation cannot be seen or felt.
It is UV radiation, not the warmth or brightness of the sun that causes changes to skin color, damage to eyes, and other bad health effects.
what is climate change...
Direct and indirect effects of climate change on plant processes:
Phenology,
Net carbon assimilation,
Water relation,
Grain development and quality,
Nutrient acquisition and yield
Heavy metal stress
EFFECTS OF HEAVY METAL ON PLANTS
Sources of metal toxicity
Chromium, manganese, zinc, aluminum, copper, nickel
ALLUMINIUM TOXICITY IN SOIL
Inhibition of Ca Uptake by AIuminium
Aluminium tolerance in soil by internal accumulation
Aluminium tolerance in soil by exclusion
CADMIUM TOXICITY IN SOIL
CADMIUM ACCUMULATION IN PLANTS
CADMIUM TOXICITY IN PLANTS
CADMIUM TOLERANCE MECHANISM
ROLE OF PHYTOCHELATINS
intro-classification-salt accumulation in soil imapairs plant function and soil structure-physiological effects on crop growth and development-osmotic effect and specific ion effects-plant use different strategies to avoid salt injury
impact of climate change on disease developement and managementprakash mani kumar
climate play an important role in the disease developement in plant. the effects of changes in temperature, CO2 and ozone concentrations, precipitation, and drought on the biology of pathogens and their ability to infect plants and survive in natural and agricultural environments. The climate influences the incidence as well as temporal and spatial distribution of plant diseases. Climate affects all life stages of the pathogen and host and clearly poses a challenge to many pathosystems.
A heavy metal is toxic when relatively it is dense metal or metalloid that is noted for its potential toxicity, especially in environmental contexts.
Heavy metal toxicity means excess of required concentration or it is unwanted which were found naturally on the earth, and become concentrated as a result of human caused activities.
Then enter in plant, animal and human tissues via inhalation, diet and manual handling, and can bind to, and interfere with the functioning of vital cellular components.
Here, it is a brief presentation regarding nanofertilizer, in relation to its role in enhancing the use efficiency of concerned nutrient, along with some experimrntal findings. Thank you for ur kind consideration.
Salinity stress
Categorization of salt affected soils
CAUSES OF SALINITY IN SOIL
Salinity effects on Plants
Injuries due to salt stress
different strategies to avoid salt injury
salt tolerance
salt avoidance
salt evasion
halophytes
non halophytes
glycophytes
Breeding for salt tolerance
Determination of soil available nitrogen by Alkaline
permanganate method (Subbiah and Asija, 1956).
Nitrogen is necessary for all forms of life. It is most important
essential plant nutrient for crop production as it is constituted the building blocks of almost all the plant structures.
Heavy metal stress
EFFECTS OF HEAVY METAL ON PLANTS
Sources of metal toxicity
Chromium, manganese, zinc, aluminum, copper, nickel
ALLUMINIUM TOXICITY IN SOIL
Inhibition of Ca Uptake by AIuminium
Aluminium tolerance in soil by internal accumulation
Aluminium tolerance in soil by exclusion
CADMIUM TOXICITY IN SOIL
CADMIUM ACCUMULATION IN PLANTS
CADMIUM TOXICITY IN PLANTS
CADMIUM TOLERANCE MECHANISM
ROLE OF PHYTOCHELATINS
intro-classification-salt accumulation in soil imapairs plant function and soil structure-physiological effects on crop growth and development-osmotic effect and specific ion effects-plant use different strategies to avoid salt injury
impact of climate change on disease developement and managementprakash mani kumar
climate play an important role in the disease developement in plant. the effects of changes in temperature, CO2 and ozone concentrations, precipitation, and drought on the biology of pathogens and their ability to infect plants and survive in natural and agricultural environments. The climate influences the incidence as well as temporal and spatial distribution of plant diseases. Climate affects all life stages of the pathogen and host and clearly poses a challenge to many pathosystems.
A heavy metal is toxic when relatively it is dense metal or metalloid that is noted for its potential toxicity, especially in environmental contexts.
Heavy metal toxicity means excess of required concentration or it is unwanted which were found naturally on the earth, and become concentrated as a result of human caused activities.
Then enter in plant, animal and human tissues via inhalation, diet and manual handling, and can bind to, and interfere with the functioning of vital cellular components.
Here, it is a brief presentation regarding nanofertilizer, in relation to its role in enhancing the use efficiency of concerned nutrient, along with some experimrntal findings. Thank you for ur kind consideration.
Salinity stress
Categorization of salt affected soils
CAUSES OF SALINITY IN SOIL
Salinity effects on Plants
Injuries due to salt stress
different strategies to avoid salt injury
salt tolerance
salt avoidance
salt evasion
halophytes
non halophytes
glycophytes
Breeding for salt tolerance
Determination of soil available nitrogen by Alkaline
permanganate method (Subbiah and Asija, 1956).
Nitrogen is necessary for all forms of life. It is most important
essential plant nutrient for crop production as it is constituted the building blocks of almost all the plant structures.
Radioactive contamination occurs when radioactive material is deposited on or in an object or a person. Radioactive materials released into the environment can cause air, water, surfaces, soil, plants, buildings, people, or animals to become contaminated.
Similar to Ozone depletion and UV radiations leading to increased ionizing radiations and its implications on crop growth. (20)
1. STABILITY OF MALE STERILE LINES - ENVIRONMENTAL INFLUENCE ON STERILITY - EGMS - TYPES AND INFLUENCE ON THEIR EXPRESSION, GENETIC STUDIES.
2. PHOTO SENSITIVE GENETIC MALE STERILITY AND ITS USES IN HETEROSIS BREEDING
3. TEMPERATURE SENSITIVE GENETIC MALE STERILITY AND ITS USES IN HETEROSIS BREEDING
FERTILITY RESTORATION IN MALE STERILE LINES AND RESTORER DIVERSIFICATION PROG...Rachana Bagudam
1. FERTILITY RESTORATION IN MALE STERILE LINES AND RESTORER DIVERSIFICATION PROGRAMMES.
2. CONVERSION OF AGRONOMICALLY IDEAL GENOTYPES INTO MALE STERILES.
3. GENERATING NEW CYTONUCLEAR INTERACTION SYSTEM FOR DIVERSIFICATION OF MALE STERILES.
Gene stacking is a type of gene cloning that refers to the process of combining two or more genes of interest into a single plant. The emerging combined traits from this process are called stacked traits. A genetically engineered crop variety that bears stacked traits is called a biotech stack or simply stack.
Heterotic group “is a group of related or unrelated genotypes from the same or different populations, which display similar combining ability and heterotic response when crossed with genotypes from other genetically distinct germplasm groups.”
A new era of genomics for plant science research has opened due the complete genome sequencing projects of Arabidopsis thaliana and rice. The sequence information available in public database has highlighted the need to develop genome scale reverse genetic strategies for functional analysis (Till et al., 2003). As most of the phenotypes are obscure, the forward genetics can hardly meet the demand of a high throughput and large-scale survey of gene functions. Targeting Induced Local Lesions in Genome TILLING is a general reverse genetic technique that combines chemical mutagenesis with PCR based screening to identity point mutations in regions of interest (McCallum et al., 2000). This strategy works with a mismatch-specific endonuclease to detect induced or natural DNA polymorphisms in genes of interest. A newly developed general reverse genetic strategy helps to locate an allelic series of induced point mutations in genes of interest. It allows the rapid and inexpensive detection of induced point mutations in populations of physically or chemically mutagenized individuals. To create an induced population with the use of physical/chemical mutagens is the first prerequisite for TILLING approach. Most of the plant species are compatible with this technique due to their self-fertilized nature and the seeds produced by these plants can be stored for long periods of time (Borevitz et al., 2003). The seeds are treated with mutagens and raised to harvest M1 plants, which are consequently, self-fertilized to raise the M2 population. DNA extracted from M2 plants is used in mutational screening (Colbert et al., 2001). To avoid mixing of the same mutation only one M2 plant from each M1 is used for DNA extraction (Till et al., 2007). The M3 seeds produce by selfing the M2 progeny can be well preserved for long term storage. Ethyl methane sulfonate (EMS) has been extensively used as a chemical mutagen in TILLING studies in plants to generate mutant populations, although other mutagens can be effective. EMS produces transitional mutations (G/C, A/T) by alkylating G residues which pairs with T instead of the conservative base pairing with C (Nagy et al., 2003). It is a constructive approach for users to attempt a range of chemical mutagens to assess the lethality and sterility on germinal tissue before creating large mutant populations.
The term balanced tertiary trisomic has three words of which (1) “trisomic” indicates the presence of extra chromosome, (2) “tertiary” indicates that the extra chromosome is a trans-located chromosome, and (3) “balanced” refers to the breeding behaviour of the trisomic.
Ramage defined the BTT as a tertiary trisomic constructed in such a way that the dominant allele of a marker gene, closely linked with the translocation breakpoint of the extra chromosome is carried on the extra chromosome, and the recessive allele is carried on the two normal chromosomes that constitute the diploid complement. The dominant marker gene may be located on the centromere segment or the trans-located segment of the extra chromosome.
The concept of gene for gene hypothesis was first developed by Flor in 1956 based on his studies of host pathogen interaction in flax, for rust caused by Melampsora lini. The gene for gene hypothesis states that for each gene controlling resistance in the host, there is corresponding gene controlling pathogenicity in the pathogen. The resistance of host is governed by dominant genes and virulence of pathogen by recessive genes. The genotype of host and pathogen determine the disease reaction. When genes in host and pathogen match for all loci, then only the host will show susceptible reaction. If some gene loci remain unmatched, the host will show resistant reaction. Now gene – for –gene relationship has been reported in several other crops like potato, sorghum, wheat, etc. The gene for gene hypothesis is also known as “Flor Hypothesis.”
Plants are continually exposed to harsh environmental conditions which is life- threatening for their survival. Drought is one of the major environmental constraints that highly affect plant growth and productivity worldwide. Osmotic stress due to limited availability of water during drought lead to the inhibition of photosynthesis which ultimately affect plant growth, yield and productivity. As sessile in nature, plants cannot escape from such adverse situations. Hence, to cope up with these adverse situations, plants have developed a complex array of adaptive strategies including intricate regulation of cellular, physiological, biochemical and metabolic processes to avoid or tolerate cellular dehydration. Under limited water availability, stomata plays an essential role to check water loss due to transpiration. In addition, upon perception of stress signal, a wide range of signaling cascade has been activated which ultimately initiates the expression of stress-responsive genes in a timely and coordinated manner. Abscisic acid (ABA), the universal stress hormone, highly accumulated under stress condition, also plays an important role in stress adaptation including stomatal closure and expression of stress-responsive genes. In recent times, whole genome sequencing analysis of different plants reveals that a large family of genes is expressed under different types of abiotic stresses that are involved in defense-related pathways. These genes can be grouped into three categories, genes involving recognition of osmotic stress, signal perception, and transduction and production of stress-adaptive components for physiological responses.
The nanotechnology aided applications have the potential to change agricultural production by allowing better management and conservation of inputs of plant and animal production. Several nanotechnology applications for agricultural production for developing countries within next 10 years has been predicted (Salamanca–Buentella et al., 2005).
Nanoparticles helps in Controlling the Plant Diseases, application of agricultural fertilizers, pesticides, antibiotics, and nutrients is typically by spray or drench application to soil or plants, or through feed or injection systems to animals. In this context, nanotechnologies offer a great opportunity to develop new products against pests (Caraglia et al., 2011). Nanoscale devices are envisioned that would have the capability to detect and treat an infection, nutrient deficiency, or other health problem, long before symptoms were evident at the macro-scale. The overall goal of this Nanoparticles is to reduce the number of unnecessary problems in agriculture (Thomas et al., 2011). In the management aspects, efforts are made to increase the efficiency of applied fertilizer with the help of nano clays and zeolites and restoration of soil fertility by releasing fixed nutrients (Dongling Qiao, et al., 2016). Nanoherbicides are being developed to address the problems in perennial weed management and exhausting weed seed bank. Bioanalytical Nanosensors are utilized to detect and quantify minute amounts of contaminants like viruses bacteria, toxins bio-hazardous substances etc. in agriculture and food systems (Tothill EI, 2011).
In this way, nanotechnology can be used as an innovative tool for delivering agrochemicals safely. More research should be done on the potential adverse effects of nanomaterials on human health, crops and the environmental safety. It is a challenge to Government and private sector as they have to ensure the acceptance of Nano foods. For it to flourish, continuous funding and understanding on the part of policy makers and science administrators, along with reasonable expectations, would be crucial for this promising field.
Stability analysis and G*E interactions in plantsRachana Bagudam
Gene–environment interaction is when two different genotypes respond to environmental variation in different ways. Stability refers to the performance with respective to environmental factors overtime within given location. Selection for stability is not possible until a biometrical model with suitable parameters is available to provide criteria necessary to rank varieties / breeds for stability. Different models of stability are discussed.
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 .
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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.
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.
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.
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.
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.
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.
Ozone depletion and UV radiations leading to increased ionizing radiations and its implications on crop growth.
1. TOPIC
1. Ozone depletion leading to increased ionizing
radiations and its implications on crop growth.
2. UV-B radiation- Effect of UV-B radiation on plant
processes and crop growth.
B.Rachana
RAD/2018-18
Ph.D 1st year
(GPBR)
CP-605 Climate Change and
Crop Growth
3. WHAT IS OZONE?
Ozone is a highly reactive gas
composed of three oxygen atoms.
There is only 3 molecules of ozone for every ten
million molecules of air.
WHAT IS THE OZONE LAYER?
The ozone layer is a deep layer of invisible gas
in the stratosphere, encircling the Earth, that has
large amounts of ozone in it.
4. Ozone-Oxygen Cycle
• Free radicals,
like chlorine ,
act as
catalysts to
the
decomposition
step (breaking
down ozone)
• These
catalysts
speed up the
reaction.
6. WHAT ARE ULTRAVIOLET (UV)
RAYS?
U.V. rays are the most common and harmful rays
that come to Earth from the sun.
WHY DO WE NEED TO KNOW
WHAT THEY ARE?
They are an important effect of ozone depletion
that has a variety of problems for living
organisms associated with it.
7. WHAT IS OZONE DEPLETION?
Due to human activity, the ozone layer is getting
weaker, causing a hole to appear and
ultraviolet rays to enter into the Earth.
9. The Dobson Unit is the most common unit for measuring ozone concentration
100 Dobson units – Least Amount of Ozone
500 Dobson units – Most Amount
10. CAUSE OF OZONE DEPLETION
• Chlorofluorocarbons (CFC) - a chemical
used to make refrigerators, home
insulation, plastic foam, and throwaway
food containers.
– Discovered in the 1930s by scientist Thomas
Midgley.
– Non-toxic, non-flammable, and non-reactive
with other chemical compounds.
– Made up of chlorine, fluoride, and carbon.
11. Destruction of ozone by chlorine
Molecular oxygen is broken down in the stratosphere by solar
radiation to yield atomic oxygen, which then combines with
molecular oxygen to produce ozone. The ozone is then
destroyed by chlorine atoms.
12.
13. To humans and
animals
To
plants
To Eco-
system
i. Blindness due to UV ray explosion
ii. Undesirable mutation (UV is a physical
mutagen)
iii. Cataracts and other eye related disease
iv. Burning skin extreme bleeding
v. If any human remaining in the surface they
would suffocate by
cancer like deadly diseases
i. UV-B generally reduce size, productivity and
quality of plants
ii. Disturbance in photosynthesis
iii. Destruction of plant cell
i. Carbon concentration will shoot and a
great decrease in
Oxygen concentration
ii. The ice in Antarctica will start to melt
iii. Total collapse in balance of ecosystem
14. SOLUTIONS THAT ADDRESS
OZONE DEPLETION
– Don’t use the air conditioner or use it less often. Open up
windows.
– Don’t open the refrigerator for too long. Get only what you
need, don’t linger.
– Refrain from using aerosol cans. You can use paper towels
to wipe off the dust.
– Fire extinguishers are essential, but to prevent using it, you
can try to prevent fires from occurring.
– Don’t use hairsprays.
– Montreal Protocol: an international agreement to
discontinue products with harmful chemicals affecting the
ozone layer and instead replace them for an ozone friendly
brand.
15. MONTREAL PROTOCOL
Agreement established to protect the
ozone layer by reducing the
production and consumption of
harmful substances in 1987. It
entered into force 1989 and if all
countries commit to its goal, the
ozone layer will be completely
regenerated by 2055
18. Ultraviolet
radiation
• Ultraviolet radiation (UVR) covers a small part of
electromagnetic spectrum lying between visible light and
X ray region
• UVR are invisible to the human eyes
• Natural source of UVR is sun
19. Types of
UVR
• 1. UVA (Long UV) – 400 – 315nm. {penetrates to dermis,
Responsible for development of slow natural tan}
• UVA is further divided into two wave ranges, UVA I,which
measures 340-400 nanometers , and UVA II which extends
from320- 340 nanometers
• 2. UVB (medium UV,erythemal UV) –
315 – 280nm. {Produces new pigment formation, sunburn, Vitamin D
synthesis.
Responsible for inducing skin cancer}
• 3. UVC (short UV,germicidal UV) –
280 – 100nm {Does not reach the surface of theearth}
most UVC is absorbed by the ozone layer and does not reach the
earth.
20.
21. How do we measure UV
radiation levels?
oWe use the UV Index Scale.
oReported on a scale of 1 -11+.
oTake special care when the UV
Index is 5-6 or higher.
22. Positive effects of UVB
Triggers vitamin D – helps strengthen bones,
muscles and the body’s immune system.
Helps some animals’ vision – Some animals
(including birds, bees and reptiles) are able to
see into the near UV light to locate many ripe
fruits, flowers and seeds that stand out more
strongly from the background.
Aids some insects navigation – Many insects use
UV emissions from celestial objects as
references for navigating in flight.
23. EFFECT ON
MICROBES
• Sterilizing effect
• Both UV B and UV C may induce T=T dimer
formation in DNA strands
• Visible light and UV A influence recovery
from UV B injury
EFFECT OF UV B ON
BIOLOGICAL SYSTEM
24. EFFECT ON
MARINE
• Large sensitivity of most phytoplankton
organisms towards UV B.
• Seem to be under UV stress
• Affect growth, photosythesis, nitrogen
incorporation and enzyme activity
25. EFFECT ON
HUMAN
•UVA/B rays make it through our
atmosphere
•UVB rays cause sunburns.
•UVA rays go deeper in the skin
and cause wrinkles.
•All UV rays damage skin
increasing the risk of skin
cancer
26. •Solar UV radiation is 95% UVA
& 5% UVB.
•UVA causes tanning, aging &
skin cancer.
•UVB causes burning & skin
cancer.
•Tanning beds emit 2-3 times
more UVA than the sun.
•UV A does not produce vitamin
D.
27. EFFECT OF UV B ON
PLANTS
• Direct effect
• DNA damage
• Cyclobutane dimer formation
• Photosynthesis
• Disturbance for photosystem 1
• Thylakoid membrane disfunctioning
• Stomatal functioning altered
• Membrane functioning
• Peroxidation of unsaturated fatty acids
• Damage to membrane proteins
30. DNA & UV-B
• DNA absorbs UV-B radiation
• Changes shape in DNA
– Changes in the DNA molecule mean
that enzymes cannot “read” the DNA
code
– Results in mutated cells or the cells
die
• Cells have developed the ability to
repair DNA
– A special enzyme arrives at the
damage site
– removes the damaged section of
DNA
– replaces it with the proper
components
• This makes DNA somewhat
resilient to damage by UV-B
31. Flowering
• UV-B radiation can alter
both the time of flowering
as well as the number of
flowers in certain species.
• Differences in timing of
flowering may have
important consequences
for the availability of
pollinators.
32. • Physiological and developmental processes of plants are
affected by UVB radiation, even by the amount of UVB in
present-day sunlight.
• A number of economically important species of plants,
such as rice, depend on cyanobacteria residing on their
roots for the retention of nitrogen. Cyanobacteria are
sensitive to UV light and they would be affected by its
increase.
• Thinning of the ozone layer also interfere with the
photosynthetic process of plants.
• Many species of crops like sweet corn, soybean, barley,
oats, cow peas, carrots, cauliflower, tomato, cucumber,
peas and broccoli are highly sensitive to UV-B radiation.
As a result, food production could be reduced by 10% for
every 1% increase of UV-B radiation.
33. Can plants protect themselves against increased UV-
B?
• The reproductive parts of plants, such as pollen
and ovules are well shielded from solar UV-B
radiation.
• Only a small proportion of the UV-B radiation
striking leaf penetrates into the inner tissues.
• Increased thickness of leaves reducing the
proportion of inner tissues exposed to UV-B
radiation.
• Have repair mechanisms in plants
–includes repair systems for DNA damage