The document discusses several theories on the origin of life on Earth, including theories of special creation, spontaneous generation, biogenesis, biochemical evolution, and panspermia. It also describes experiments like the Urey-Miller experiment and the hypothesis that life began near deep sea hydrothermal vents, which provided chemical gradients and concentrations that could have led to the formation of organic molecules and eventually early life forms. Recent research has provided new insights but many questions around the exact mechanisms of how life first emerged on our planet remain unanswered.
Origin of life-where did life come fromArosek Padhi
this chapter prompts you to wonder where did life as we know it came from. this is a presentation from Dr.Tithi Parija (asst professor) from KIIT school of biotechnology including different theories from different thinkers and scientists
Life, living matter are those that shows certain attributes that include responsiveness, growth, metabolism, energy transformation and reproduction.
In biology origin of life or abiogenesis is the natural process by which life has arisen from non-living matter, such as simple organic compounds.
It means the emergence of heritable and evolvable self-reproduction.
It is a complex subject and oftentimes controversial.
Several attempts have been made from time to time to explain the origin of life on earth.
There are several theories which offer their own explanation on the possible mechanism of origin of life.
Origin of life-where did life come fromArosek Padhi
this chapter prompts you to wonder where did life as we know it came from. this is a presentation from Dr.Tithi Parija (asst professor) from KIIT school of biotechnology including different theories from different thinkers and scientists
Life, living matter are those that shows certain attributes that include responsiveness, growth, metabolism, energy transformation and reproduction.
In biology origin of life or abiogenesis is the natural process by which life has arisen from non-living matter, such as simple organic compounds.
It means the emergence of heritable and evolvable self-reproduction.
It is a complex subject and oftentimes controversial.
Several attempts have been made from time to time to explain the origin of life on earth.
There are several theories which offer their own explanation on the possible mechanism of origin of life.
How life originated on earth is still a very tough question. We have found many evidences, we have a lots of hypothesis, but still we have miles to go. This PPT summarizes the findings of research on origin of life on earth.
TOPICS:
• THE CONCEPT OF LIFE
• WHAT QUALIFIES SOMETHING AS “LIVING”?
o MOVEMENT
o SENSITIVITY
o DEATH
o COMPLEXITY
• THEORIES ON THE ORIGIN OF LIFE
o EXTRATERRESTRIAL ORIGIN
o PANSPERMIA
o DIVINE CREATION
o ORIGIN FROM NONLIVING MATTER (PHYSICO-CHEMICAL THEORY)
• FORMATION OF THE FIRST CELL
• EARLY LIFE FORMS
Earth and Life Sciences for Senior High School by Duyanen and Andaya pages 176-179
My fun and colorful grade 11 report on Life Sciences 2nd semester of A.Y. 2016-2017 under Ms. Lagmay
How life originated on earth is still a very tough question. We have found many evidences, we have a lots of hypothesis, but still we have miles to go. This PPT summarizes the findings of research on origin of life on earth.
TOPICS:
• THE CONCEPT OF LIFE
• WHAT QUALIFIES SOMETHING AS “LIVING”?
o MOVEMENT
o SENSITIVITY
o DEATH
o COMPLEXITY
• THEORIES ON THE ORIGIN OF LIFE
o EXTRATERRESTRIAL ORIGIN
o PANSPERMIA
o DIVINE CREATION
o ORIGIN FROM NONLIVING MATTER (PHYSICO-CHEMICAL THEORY)
• FORMATION OF THE FIRST CELL
• EARLY LIFE FORMS
Earth and Life Sciences for Senior High School by Duyanen and Andaya pages 176-179
My fun and colorful grade 11 report on Life Sciences 2nd semester of A.Y. 2016-2017 under Ms. Lagmay
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
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2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
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Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
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We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
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Reverse Pharmacology.
2. INTRODUCTION
Several attempts have been made from time to time to explain
the origin of life on earth.
As a result, there are several theories which offer their own
explanation on the possible mechanism of origin of life.
Following are some of them:
• Theory of Special Creation
• Theory of Spontaneous Generation
• Theory of Biogenesis
• Theory of Biochemical Evolution
• Theory of Panspermia
• Deep sea hydrothermal vent theory
3.
4. • All the different forms of life -
created by God.
• HINDU CONCEPT :- Lord Brahma-
created the living world in one stroke.
• CHRISTIAN & ISLAM BELIEF :-
God created this universe, plants,
animals and human beings in about
six days.
• 3 main postulates :
– All different kinds of animals &
plants were created at once.
– All organisms were created in the
same form in which they exist
today.
– Their bodies & organs have been
designed to fully meet the needs
of the environment.
• It has no scientific basis.
6. • Living things originated spontaneously from inanimate objects.
• It is also called abiogenesis or biopoesis.
• Supporters :- Aristotle
» Epicurus
» Von Helmont
• They believed
» Insects arise from dew
» Fish & frog from mud
» Fly maggots from meat .
• Opposers
» Fransisco Redi
» Spallanzani
» Louis pasteur
• The opposers disproved this theory.
Redi’s experiment
Pasteur’s experiment
7.
8. •Proposed by Richter in 1865 and supported by Arrhenius.
•Life had come to earth from other planets of the universe, in the
form of resistant spores.
•British astronomers Fred Hoyle and Chandra Wickramasinghe
proposed:
•interstellar dust and comets contain organic compounds.
•comets, which are largely made of water-ice, carry bacterial life
across galaxies and protect it from radiation damage along the way.
• The 2005 Deep Impact mission to Comet Tempel 1 discovered a
mixture of organic and clay particles inside the comet.
Credit: Hoover/Journal of Cosmology
Dr. Richard B. Hoover, an astrobiologist
with NASA’s Marshall Space Flight Center
published a paper on March 4, 2011, claiming
to have found fossil evidence for
cyanobacteria in an extremely rare class of
meteorites, called CI1 carbonaceous
chondrites .
9. SOME OTHER THEORIES…….
• Theory of Eternity of life: Life only changes its form but is never created.
It has no origin and has always existed.
• Theory of catastrophism
– modification of the theory of Special Creation.
– States that there have been several creations of life by God, each
preceded by a catastrophe resulting from some kind of geological
disturbance.
– Since each catastrophe completely destroyed the existing life, each new
creation consisted of life form different from that of previous ones.
– Main supporters : French scientists Georges Cuvier and Orbigney
• Vitalism :
– Only living tissue, by virtue of possessing some "life-force," can
produce organic compounds.
– Supporters: Berzelius and Bergson.
– The production of acetic acid, from its elements, by the German
chemist Hermann Kolbe in 1845, disproved vitalism.
10.
11. • Also known as Materialistic Theory or Physico-chemical Theory.
• Proposed independently by a Russian scientist, A.I.Oparin, in
1923 and an English scientist, J.B.S Haldane, in 1928.
According to this theory,
• Life first arose from a collection of chemical
substances by a progressive series of reactions.
• Early Earth's surface and atmosphere –
radically different from today’s condition.
• The primitive earth's atmosphere -reducing type.
• Solar radiation and lightning must have been the chief energy
source for these chemical reactions.
• The organic compounds gradually accumulated in oceans and
formed a ―hot primordial soup‖ or ―hot dilute soup‖.
• Also known as ―Darwin’s warm little pond‖
12. • Oparin proposed that the proteinoids, nucleo
proteins and other organic and inorganic
molecules aggregated and precipited in sea
forming organized colloid aggregates called
coacervates.
• The coacervates were able to absorb and
assimilate organic compounds from the
environment in a way reminiscent of
metabolism.
• They divided by budding.
• Oparin considered that the coacervates gave rise
to primitive cells or Eubionts.
• Sydney fox obtained proteinoid microspheres
by heating a mixture of dry amino acids b/w
130 to 1800C and later cooling them in water.
• It was similar to coccoid bacteria.
Coacervates
Microspheres
14. DRAWBACKS OF UREY MILLER EXPERIMENT
• By examining rocks ―dated‖ to be 3.7 billion years old,
geologists determined that earth had an oxygenic atmosphere.
• Oxygen is an ―oxidizing‖ agent and would inhibit chemical
evolution.
• Experiment produced a mixture of right-handed & left handed
amino acids, but in nature left handed ones predominate.
• Now it is thought that the atmosphere of the early earth was
not rich in methane and ammonia — essential ingredients in
Miller's experiments.
15.
16. • Recently some scientists put forth a hypothesis
that life originated near a deep sea hydrothermal
vent.
• Black smoker hydrothermal vent
– first discovered vents
– produced extremely hot water, 3500 C
– not conducive to micro-chemical evolution.
• Lost City hydrothermal field
– Alkaline vents in mid- Atlantic ocean.
– discovered by Kelley and others in 2000.
– Much cooler- temp of water – 70-900C
– They are porous,honey-combed with cavities.
– The cavities are at a scale of 1 micron –
the same size as a living cell.
– The cavity walls are saturated with iron-
sulfur(Fe-S) mineral catalysts.
17. H2 +CO2 simple organic molecule (CH4, formate & acetate.)
Serpentinization :- chemical reactions between seawater and
mantle rocks which contain large amounts of the mineral
olivine (a Mg-Fe silicate)
H2O was reduced by Fe2 ; H2 & S released.
At the vent ocean interface sulphur precipitate, Iron, Nickel etc
transition metal sulphides.
They catalyse H2 dependent reduction of CO2 to CO
CO + H2S CH3-CO-SCH3 (methyl thioester of acetic acid)
These activated acetic acid derivatives serve as starting materials
for subsequent exergonic synthetic steps.
Vent pores concentrated large molecules like nucleotides
formation of RNA, DNA , proteins
NiS
FeS
18.
19. RECENT DEVELOPMENTS
– In April 2011, researchers in Italy found that if they mixed formamide, a
simple chemical present in space, with material from a meteorite, and then
heated the mixture, that they produced nucleic acids (building blocks of
DNA and RNA), the amino acid glycine, and a precursor to sugar.
– In February 2010 scientists at the Scripps Research Institute in San Diego
announced that they have synthesized RNA enzymes, known as ribozymes,
that can replicate themselves without the help of any proteins or other
cellular components.
– In May 2009, a team led by John Sutherland, a chemist at the University of
Manchester in England discovered how the basic nucleotides (building
blocks) of RNA could spontaneously assemble . He formed the RNA
nucleotide ribocytidine phosphate from cyano-acetylene.
20. CONCLUSION
• All the evidence gathered thus far has revealed a great deal
about the origin of life, but there is still much to learn.
• Numerous scenarios have been explored for many years, but
there is still a large gap between what is known and what is
unknown.
• Because of the enormous length of time and the tremendous
change that has occurred since then, much of the evidence
relevant to origins has been lost and we may never know
certain details.
• Nevertheless, many of the gaps in our knowledge (gaps that
seemed unbridgeable just 20 years ago) have been filled in
recent years, and continuing research and new technologies
hold the promise of more insights.
21. REFERENCES
• Strickberger W Monroe (2000), Evolution, 3rd edition, Jones and Bartlett
Publishers.
• Arora P Mohan . (2000), Evolutionary Biology ,3rd edition, Himalaya
Publishing House
• http://www.foxnews.com/scitech/2011/03/05/exclusive-nasa-scientists-
claims-evidence-alien-life meteorite/#ixzz1cvC7Bge8
• http://www.smashinglists.com/top-10-theories-on-beginning-of-life-on-
earth/
• http://mannaismayaadventure.wordpress.com/2011/06/24/
• http://www.tutorvista.com/content/biology/biology-iii/origin-life/origin-
life-theories.php
• http://www.dailykos.com/story/2011/04/03/962923/-Revolutionary-
Science:-Hydrothermal-Vents-and-the-Origins-of-Life
• http://www.youtube.com/watch?v=j_flx26bU0Q&feature=related