Emergence of Organic Molecules
Early Earth and Early Universe
Classwork
1. Briefly explain the biochemical experiment performed by Miller-Urey and its significance
to the origin of living organisms.
2. The Earth is believed to be 4.5 billion years old. What evidence do scientists use to
make this statement?
3. You are probably most familiar with the name Hubble from the Hubble telescope
launched by NASA in 1990. What evidence did Edwin Hubble use to help support the
Big Bang theory?
4. Where do scientist believe all the natural elements that make up the Earth originally
came from?
5. Scientists have come up with the acronym LUCA. What do the letters stand for? Briefly
describe the basis for this hypothesis.
6. Discuss the uniqueness of the chemical and physical properties of the water molecules,
and the significance of these properties to life on Earth.
7. What sequence of events would occur in a lake as winter progresses, if solid water were
more dense the liquid water, as is the case with most molecules?
8. Describe the two parts that make up a solution.
9. Living organisms use buffers to help maintain a steady pH in their internal environment.
Human blood has buffers. The buffer contains a large reservoir of an acid and a base.
When something is added to the blood the buffer will either bind with excess hydroxide
ions or excess hydrogen ions keeping them from affecting the overall pH. This helps
maintain the needed blood pH at about 7.4. Describe the buffering system that is used
in human blood.
Homework
Article Review: “Universe as an Infant: Fatter Than Expected and Kind of Lumpy” by Dennis
Overbye
http://www.nytimes.com/2013/03/22/science/space/planck-satellite-shows-image-of-infantuniverse.html?ref=space
(note: the NY Times website may ask you to create an account to access the article)
10. What is the significance of the heat map image of the early cosmos?
11. What do you think the scientist mean by the statement: “the universe appears to be
slightly lumpier”?
12. It seems every time we read an article scientist are always correcting old theories. Why
should we bother to believe any of them, if they are going to change in the future?
13. What is the significance of the hot spots in the microwaves?
14. What do the scientists mean by the “dark matter”?
15. When examining the water molecule and its polarity, where is the slightly positive
charge located, and where is the slightly negative charge located?
16. If you drop your drink on the floor during dinner, and place a paper towel over the spilled
drink to clean it up, what process is occurring as you witness the paper towel pick up the
drink?
17. Would you expect more temperature and weather fluctuations to occur in Oklahoma or
New Jersey? Explain.
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Emergence of Organic Molecules
Biological Molecules
Classwork
18. Starches are called complex carbohydrates when speaking in terms of nutrition. What
kind of reaction must occur to break it down in to smaller components? Describe the
reaction in detail.
19. Metabolism involves the building and breaking down of molecules in you body. Using
molecular models, sketch two monosaccharides being joined together by dehydration
synthesis. Be sure and circle where the H and OH came from on the monosaccharide.
20. If you had a polymer 15 monomers long how many water molecules would be needed to
break the molecule down completely? Include a drawing and use arrows to indicate the
point of breakage.
21. What evidence exists that supports the “organic monomers from space” theory?
22. From Stanley Miller’s experiment to create organic monomers from reactions, what 4
conditions had to be present on primitive earth to allow this to happen?
23. Polysaccharides can be use for storage and structure. Describe a plant and animal
storage and structural polysaccharide.
24. Sugar is a general term used in our world today. What is the biological definition of a
sugar? Explain the difference between monosaccharide and disaccharides.
25. Salad is excellent roughage for our digestive system. Although most people love the
taste, this biological molecule is indigestible by the humans. Cows on the other hand
are herbivores whose entire diet tends to be grass. What kind of biological molecule
found in plants can’t we digest? How are cows able to digest grass?
26. Write the equations used to make the 3 disaccharides sucrose, maltose and lactose.
27. If human DNA were stretch out, it would be over 6 feet long (2 meters) and is made of
over 3 billion base pairs. Although these facts seem daunting, if you look closely you will
see that each base pair is part of a small repeating unit called a nucleotide. Describe a
nucleotide and sketch for of them, each contains one of the bases found in DNA.
28. Compare and contrast DNA and RNA. Please include as much detail as possible in your
answer.
29. Below is one stand of a DNA molecule. How did Chargaff findings contribute to what we
know about base parings? Also sketch both sides of the molecules.
5’ ATTGCAG 3’
30. DNA to RNA to Protein is the central dogma of molecular biology. As we have learned
proteins are major part of a living organisms cellular activities. Describe the four levels
of protein structure in as much detail as you can.
31. The idea of protein synthesis happening outside the nucleus of the cell baffled scientist
up until experiments using cell fractionation were able to isolate the source of protein
synthesis. Describe the process of protein synthesis from DNA to protein assembly.
32. Biological molecules are often made of repeating units held together by unique bonds.
Describe the reaction for amino acid being joined together to form polypeptides. Please
include a sketch of two amino acids becoming a dipeptide.
33. Many scientists often refer the N terminus and the C-terminus. State what these refer to
and sketch and label an amino acid showing both terminus ends.
34. Describe the main functions of lipids. Discuss the difference between saturated and
unsaturated lipids.
35. Discuss carbohydrates, proteins and lipids with respect energy contained within each of
them.
36. Omega-3 and Omega-6 oils are considered the so-called good fats. What is unique
about the structure of “good” fats? What is a good dietary source of these fats?
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Emergence of Organic Molecules
37. Fat, waxes, oils, and steroids all fall under the category of lipids. Two common lipids are
phospholipids and triacylglycerol. Explain how their structure differs and how this affects
the molecules when they come in contact with water.
Homework
38. How does hydrolysis participate in energy storage and metabolism?
39. When two carbohydrates are joined via dehydration synthesis, what is the link called that
joins them together?
40. What is it about today’s atmosphere in relation to primitive Earth’s atmosphere that
would be prohibitive to the formation of organic compounds?
41. What was Stanley Miller able to produce using inorganic molecules and high energy
input, and what was the significance of his experiment?
42. Humans do not possess the necessary enzymes to digest cellulose, however, it still aids
in digestion. How is this so?
43. Excess carbohydrates in our diet can be detrimental. What happens to excess glucose
in the human body?
44. A basketball player eats a sandwich before playing a game. At game time, what will
happen to the carbohydrates that were ingested?
45. List the two monosaccharides which form together to create the disaccharide Sucrose.
By what reaction does this occur?
46. What is the difference between a purine and a pyrimidine? Which bases are purines,
and which are pyrimidines?
47. What bonds link nucleotides together in nucleic acids?
48. When a protein denatures, what occurs? What causes a protein to denature?
49. What are the components of all amino acids, and which component determines the
unique nature of the amino acid?
50. What are the 7 types of proteins in organisms?
51. Considering the 4 levels of protein structure, what structure does hemoglobin have? Out
of the 7 types of proteins in organisms, which type is hemoglobin?
52. Describe what is meant when a lipid is described as amphiphilic. Give an example of
where we can find a lipid that displays this property.
53. When examining a phopholipid molecule, with the 2 fatty acid end, and the phosphate
end, which end is the polar end and which end is the non-polar end?
54. What is a steroid, and can you give an example with its function?
Development of Life
Classwork
55. Scientist use fossil evidence to help determine when life first arrived on our planet.
Describe how fossil can be formed.
56. When do scientist first believe life originated on our planet? And what role do
stromatolites play in this puzzle?
57. The oldest eukaryotic organism is believed to be an endosymbiont. Provide a brief
description how an endosymbiont can be formed. Also give an example.
58. LUCA is based on the idea that many organisms have similar common features. What
features of life support LUCA?
59. Describe the minimum structural, metabolic and genetic components of a primitive cell.
60. How is Evolution different from the Origin of Life?
61. Discuss Oparin and coacervates.
Homework
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Emergence of Organic Molecules
Article Review: “It’s Alive! It’s Alive! Maybe Right Here on Earth” by Dennis Overbye
http://www.nytimes.com/2011/07/28/science/28life.html
62. What do most scientists agree is essential to describing life?
63. What is the significance of scientific research in the producing life form chemicals in a
test tube?
64. Describe the significance of Dr. Joyce’s test tube results. Are his results most like LUCA
or most like a form of life we have not yet discovered, why
65. Which theory of life would these findings support?
Article Review: The Origins of Life” by Helen Fields
http://www.smithsonianmag.com/science-nature/The-Origins-of-Life.html
66. What kind of ecosystem can be found near the deep underwater ocean vents?
67. Describe Hazen's first experiments with the so-called pressure bomb.
68. Compare and contrast Hazen's Experiments with Stanley Miller’s Experiment.
69. What does Hazen mean when he uses the phrase “looking into the first step in that
courtship”?
70. Why does Hazen believe minerals play a part in the origin of life?
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Emergence of Organic Molecules
Free Response
1. Complex molecules are crucial for life processes. How these molecules came to be on
Earth is subject to ongoing speculation and research. Below are several fabricated or
real pieces of evidence that may or may not support certain hypotheses regarding the
creation of complex molecules on early Earth. Place each piece of evidence in the
correct column in the table below. State whether the evidence is real or fabricated.
Provide a justification for your decision based on current scientific thinking.
Evidence (fabricated or real)
a. The Earth was 30 million miles more distant from the sun in the early solar
system.
b. The early atmosphere was oxygen rich.
c. Complex organic molecules have been discovered in meteorites on the Earth.
d. The early atmosphere contained simple molecules such as methane, carbon
dioxide, ammonia and water.
Evidence
Supports creation of complex molecules on
Does not support creation of complex
early Earth
molecules on early Earth
Evidence
Evidence
Justification
Justification
Evidence
Evidence
Justification
Justification
Evidence
Evidence
Justification
Justification
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Emergence of Organic Molecules
2. The following diagram shows the Miller-Urey experimental setup.
a. Why did they select the
gases shown in the air mixture?
b. Describe the conclusion
that the results of the experiment support?
http://upload.wikimedia.org/wikipedia/commons/thumb/5/54/Miller-Urey_experiment-en.svg/500px-MillerUrey_experiment-en.svg.png
3. Hydrolysis, or the addition of water in between monomers, breaks up large molecules.
Dehydration synthesis is the reverse chemical reaction.
a. With reference to the diagram in question 2, would you expect to find large
molecules (many linked monomers) in the cooled water section of the apparatus?
Explain.
b. Do you think it is possible to create a cell under the physical and chemical
conditions used in the Miller-Urey experiment? Explain.
c. With reference to the diagram in question 2, how can you reduce the possibility of
hydrolysis occurring in the experiment?
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Emergence of Organic Molecules
4. Stromatolites (pictured below) are sedimentary rock that formed from layers of ancient
bacteria, such as blue-green algae, and trapped sediments over many generations
(millions to billions of years). Stromatolites are a microscopic version of the fossilization
process that formed the fossils of the dinosaurs and other macroscopic organisms.
Stromatolites are still forming and growing in places like Shark Bay, Australia.
a. If a scientist claims that life arose 6,000 years ago, 1 million years ago, or 100
million years ago, how can you use the geological and biological evidence shown
below (stromatolites of Shark Bay, Australia) to evaluate or analyze that
statement or hypothesis?
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Emergence of Organic Molecules
5. A diagram depicting the alkaline hydrothermal vents hypothesis for origin of life on Earth is
shown below.
a) Use the diagram to describe the hydrothermal vents hypothesis.
b) Why is the hydrothermal vents hypothesis more supported by evidence that the
“water soup” suggested by the Miller-Urey experiment?
Sousa FL, Thiergart et. al.. 2013 Early bioenergetic evolution. Phil Trans R Soc B 368: 20130088
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Emergence of Organic Molecules
Emergence of Organic Molecules-Answer Key
1. They created an artificial laboratory model of our ancient atmospheric gases along with
electric charges and water formation of the primitive components of organic molecules is
possible. Organic molecules are found in all living organisms.
2. Scientist use radiometric dating to date very old material. The process compares a parent
specimen’s radioactive elements quantity to a samples amount of radioactive elements
quantity. Since radioactive elements break down at a known rate. This breakdown is
called half-life. Scientists are able to use this ratio to calculate the age of the specimen.
3. Edwin Hubble used the red shift of the universe to support the Big Bang Theory.
4. All the elements on Earth were formed in reactions inside stars.
5. Last Universal Common Ancestor. The basis for this theory is that every living thing shares
characteristics, such as DNA, RNA, and ATP, that are statistically more likely to have arisen
once in a single ancestor than to have evolved multiple times.
6. Water demonstrates cohesion, the hydrogen bonds keep water molecules close to one
another. Plants rely on cohesion to bring water from roots up to leaves. Water has high
specific heat. The H bonds break when heat is absorbed and form when heat is released. In
nature it takes a tremendous amount of heat to raise the temperature by one degree
Celsius. Bodies of water, such as lakes, rivers and oceans take a long time to heat, but
once they do they hold onto that heat longer than the surrounding land. Climates and
weather are direct result of the uneven heating patterns on the earth. Water has a High
heat of vaporization, amount of heat needed to change liquid water to gaseous water. This
helps with evaporative cooling, and maintains homeostasis in living organisms. Water the
universal solvent; because of its polar nature it is able form bonds with other molecules.
The positive side of the molecules and pull them apart forming ionic bonds. This
disassociation forms aqueous solutions. Finally, water expands when it freezes. Because
water is most dense at 4 degrees Celsius, allowing ice to float. Because ponds and lakes
freeze from the bottom down, animals that overwinter have a safe place near the bottom of
the aquatic environment.
7. The particles slow down enough to change from a liquid to a solid. If water was a typical
compound any part of the liquid that froze would sink. Any living organism would have
nowhere to go over the winter. They would risk getting hit by the dense frozen liquid as it
sunk, they would also risk getting frozen themselves.
8. A solution consists of the solvent and the solute. The solvent dissolves the solute.
9. Carbonic acid is formed when carbon dioxide reacts with water in the blood plasma. The
carbonic acid than dissociates into bicarbonate and a hydrogen ion. As the blood pH shifts
from an acidic or to a basic level the reaction will move in one direction or the other. For
example if the pH in the blood begins to rise, more carbonic acid will dissociate providing
more H ion, lowering the overall blood pH. If the blood pH lowers, H ions will be removed
from the blood forming carbonic acid.
10. It showed the universe to be 80 to 100 million years older than previously thought.
11. The distribution of matter and energy throughout the universe is not consistent.
12. Opinion question
13. Hot spots in microwaves are submicroscopic quantum fluctuations which can produce
galaxies
14. Non-ordinary matter, it does not produce or absorb electromagnetic radiation
15. The two hydrogen atoms hold a slightly positive charge, while the oxygen atom holds a
slightly negative charge.
16. Capillary action due to adhesion. The water molecules are bonding with the fibers of the
paper towels and sticking there. Adhesion is defined as the attraction between a water
molecule and a non-water molecule.
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Emergence of Organic Molecules
17. This is a case where the specific heat capacity of water is considered. Due to the fact that
water has such a high specific heat capacity, cities and states with water surrounding or
bordering them have less dramatic changes in temperature and weather. Therefore, a state
in the middle of the country like Oklahoma, with no large masses of water by it will
experience more drastic changes in temperature, than a state like New Jersey on the coast
of the Atlantic.
18. Starches are broken down into monosaccharides by hydrolysis. The reaction occurs when
water interacts with the starch, breaking the covalent bonds in the starch and water. A
hydrogen atom is attached to one saccharide, while a hydroxyl group is attached to the
other.
19. A sketch similar to the one below.
20. 14 water molecules. Include a sketch
21. The dust in the solar system that created Earth was full of organic chemicals. Also,
meteorites found today that crashed into primitive Earth contain organic chemicals as well.
22. Absence of oxygen in the atmosphere as it would have broken down large organic
molecules. High Energy output in the form of the sun’s ultraviolet rays. Micromolecules
found in the ocean and atmosphere. Time for the molecules to form and react.
23. Starch is an energy storage molecule found in plants; it can be a branched or unbranched
polysaccharides. Glycogen is an energy storage molecule found in animals; it is always
highly branched. Cellulose is a structural molecule found in plants; its bonds form chains,
cross-linked by hydrogen bonds.
24. Sugars are carbohydrates that consist of the elements C, H, O in a 1:2:1 ratio. They end in
the suffix -ose. Monosaccharides consist of a single monomer, C6H12O6. Disaccharides
consist of two monomers.
25. Cellulose. Cows can digest this molecule because they have four stomach containing
microbe which break down the fiber.
26. C12H22O11; glucose + glucose = maltose, glucose + fructose = sucrose, glucose + galactose
= lactose
27. Nucleotides are composed of a phosphate, a sugar, and a nitrogenous base. Include a
sketch.
28. DNA and RNA are both made up of nucleotides with a sugar, a phosphate, and a
nitrogenous base. DNA has the sugar deoxyribose. RNA has the sugar ribose. DNA uses
the bases thymine, guanine, cytosine, and adenine. RNA uses the bases uracil, guanine,
cytosine, and adenine.
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29. Chargaff was able to isolate the bases in the DNA and show the percent of A’s is about the
same as the percent of T’s, likewise C percentage is equal to G’s.
5’ ATTGCAG 3’
3’ TAACGTC 5’
30. The primary level is the amino acid chain. The secondary level includes alpha helices and
pleated sheets created by hydrogen bonding amongst amino acids. The tertiary structure is
the overall 3D shape of the protein caused by hydrophobic interactions and disulfide bonds.
Quaternary structure occurs when multiple peptide chains interact, forming a larger protein
structure.
31. DNA is transcribed into RNA. The mRNA at the site of the ribosome codes for amino acids.
The tRNA brings them to the A site and they are joined together by dehydration synthesis.
The removal of water allows for a peptide bond to be formed.
32. Amino acids are joined through dehydration synthesis. Include a sketch
33. The C-Terminus is the carboxyl end of the amino acid and the N-Terminus in is the free
amino group end. Include a sketch
34. Lipids are energy storage molecules, components on the cell membrane, and involved in
metabolic activities as steroids. Unsaturated lipids have double and triple bonds. Saturated
lipids have only single bonds.
35. Lipids are used for longterm energy storage. Carbohydrates provide energy in the short
term. Proteins control the rate of metabolic reactions.
36. They contain carbon-to-carbon double bonds. Omega-3 fatty acids are polyunsaturated fats
found naturally in oily fish, nuts, seeds, and leafy green vegetables.
37. Phospholipids are amphiphilic. In water, they create a bilayer with hydrophilic head facing
the water and the hydrophobic tails accumulate inside the membrane. Triacylglycerol is
hydrophobic.
38. In order to break the pryphosphate linkages in ATP and release the energy within, a
hydrolysis reaction is necessary. ATP is broken down into ADP and an inorganic phosphate.
39. Glycosidic Link
40. Oxygen is present in today’s atmosphere, but was not present in early Earth’s atmosphere.
Due to oxygen’s ability to accept electrons, it would have broken down any organic
molecules that were formed.
41. Stanley Miller was able to create amino acids and other organic molecules from inorganic
molecules mirroring early Earth’s atmosphere. This lends credence to the theory that
organic monomers were created on Earth via chemical reactions.
42. As cellulose passes through the digestive tract, it stimulates the digestive tract walls to
secrete mucus which aids in digestion.
43. Excess glucose is converted to fat and stored in fatty tissue. Without exercise, this fat can
accumulate in the body.
44. Carbohydrates provide quick, short lasting energy. They will be the first to be burned up by
the player’s body.
45. Through dehydration synthesis, Glucose + Fructose yields Sucrose.
46. Purines (adenine and guanine) are 2-ringed structures. Pyrimidines (thymine, cytosine, and
uracil) are single-ringed structures. Purines form hydrogen bonds with pyrimidines in the
“complimentary base pairing” that we see in DNA and RNA.
47. Phosphodiester bonds.
48. Denaturation occurs when a protein unfolds, and loses its functionality. Factors such as pH,
changes in temperature, and salinity can all cause a protein to denature.
49. All amino acids are composed of an amine group, a carboxyl group, and a side chain that is
unique to the amino acid. The side chain is what determines the amino acid’s properties.
50. Structural, contractile, storage, defense, transport, signaling, and enzymatic.
51. Hemoglobin is a transport protein with quaternary structure.
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52. Amphiphilic means that the molecule possesses a hydrophobic end and a hydrophilic end.
Phospholipids are the most common example.
53. The phosphate end is the polar end and the fatty acid chains are the non-polar end.
54. A steroid is a lipid with a 4-ringed structure. They are essential for all life as they help
regulate reproduction, metabolism and other processes. Estrogen is a steroid produced by
females which aids in preparing for reproduction by stimulating development of reproductive
organs and growth of the uterus lining.
55. Fossil can be formed through pressure in sedimentary rock. They can also be formed form
dead organisms in tree sap, tar pits, and when minerals replace bone.
56. Scientists believe life first existed 3.5 million years ago. Stromatolites are made when
microscopic photosynthesizing cyanobacteria form microbial films that trap mud, sometimes
trapping ancient cyanobacteria within the layers.
57. The endosymbiont is formed when smaller prokaryotic cells began living within larger cells.
The most common example is the mitochondria and plastids that began living with in larger
cells.
58. LUCA is supported by the universal features of genetic code, DNA/RNA polymerases,
mRNA, tRNA, ribosomes, L-isomers of amino acids, lipid bilayers, Na+/K+ pumps, and ATP
and ATP synthases.
59. To be considered a cell, the object in question must be enclosed in a phospholipid
membrane and contain genetic information encoded in nucleic acids. It must be selfreplicating. And metabolize energy using ATP as a storage molecule.
60. Evolution provides an explanation of the diversity of life. How organisms must adapt to
selection pressures or the will die. The origin of life describes mechanisms that were able to
produce molecules that could grow and replicate as long as an energy source is present.
61. Oparin was pretty sure life originated form coacervates. These microscopic spontaneously
formed spherical aggregates of lipid molecules. He used these to show enzyme reactions
worked better within these tiny membranes.
62. The ability to evolve and adapt
63. To discover how life originated
64. Dr. Joyce evolved a molecule that could replicate and evolve by itself. This may indicate that
life can arise spontaneously.
65. It would support Oparin’s theory that life arose from inorganic molecules
66. They are hot, high-pressure environments with rich mineral deposits inhabited by giant
worms, blind shrimp and sulfur-eating bacteria.
67. His first experiments were tiny capsules that were filled with pyruvate and carbon dioxide
and put in a chamber at 2000 atm and480 degree, the experiment yielded tens of thousands
of organic molecules.
68. Miller’s experiments relied on gases of the early atmosphere and lightening to create
organic molecules at the Earth’s surface. Hazen’s experiments used similar gases but at
extreme pressure and temperatures that were at vents on ocean floor. Both produced
organic molecules.
69. Hazen and his lab are looking in how the molecules that combined to form organic
molecules actually ran into or came in contact with one another to react and form them.
70. Hazen explains there were only 50 or so minerals before life began, and with volcanoes and
plate tectonics changing the earth leading to the creation of new minerals, new chemicals –
some of them amino acids.
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Emergence of Organic Molecules
1.
Evidence
Supports creation of complex molecules on
Does not support creation of complex
early Earth
molecules on early Earth
Evidence
Evidence
C
A
Justification
Justification
This is true with prime examples being the
The Earth has never been this far away from
Murchison meteorite and ALH84001, both of the sun and so the information is fabricated.
which contained complex organic
This situation would have made it more
molecules. From this information it can be
difficult for complex molecules to arise as it
hypothesized that complex molecules may
is believed that high energy was required to
have been brought from space in great
cause the reactions necessary to make
amounts to the early earth. It is they that
them. The proximity of the sun to the earth
formed the basis of the first cells.
made high levels of radiation from the young
sun available for these reactions. Increasing
this distance by a third would have reduced
the available energy
Evidence
D
Justification
Data suggests that this is correct and that
complex molecules could have formed from
these simple ones. Miller and Urey used
this information for their experiment where
they combined these chemicals in a flask,
added an electrical spark and collected the
resultant purines, prymidines and amino
acids.
Evidence
B
Justification
This is not true as early atmosphere
contained very low concentrations of
oxygen. Levels rose only with the advent of
photosynthetic organisms 2.4B years ago
and then at a slow rate.
Free oxygen in the atmosphere would have
quickly oxidized any complex molecules
making their life short and organization into
cells highly improbable. Stability of these
molecules over great spans of time was
required for this process.
Essential knowledge 1.D.1: There are several hypotheses about the
natural origin of life on Earth, each with supporting scientific
evidence.
LO 1.27 The student is able to describe a scientific hypothesis
about the origin of life on Earth. [See SP 1.2]
LO 1.31 The student is able to evaluate the accuracy and
legitimacy of data to answer scientific questions about the origin
of life on Earth. [See SP 4.4]
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Emergence of Organic Molecules
2a. Water vapor, methane, hydrogen, carbon monoxide, and ammonia (the gas mixture) were
chosen because the geological evidence implied that the early Earth’s atmosphere consisted of
or had this particular gas mixture among others.
2b. The experiment showed that organic molecules such as amino acids, sugars, and larger
hydrocarbons could be created from inorganic molecules that were present in the early
atmosphere of Earth with the help of energetic or environmental conditions such as heat and
lighting.
Essential knowledge 1.D.1: There are several hypotheses about the natural
origin of life on Earth, each with supporting scientific evidence.
LO 1.27 The student is able to describe a scientific hypothesis
about the origin of life on Earth. [See SP 1.2]
LO 1.31 The student is able to evaluate the accuracy and
legitimacy of data to answer scientific questions about the origin
of life on Earth. [See SP 4.4]
Essential knowledge 1.D.2: Scientific evidence from many different
disciplines supports models of the origin of life.
Learning Objective:
LO 1.32 The student is able to justify the selection of geological, physical, and chemical data
that reveal early Earth conditions.
[See SP 4.1]
3a. Due to the presence of water there would be less chance of polymers forming because
water would be added between the monomers and the polymers would be decomposed.
3b. All the monomers needed to create a cell would be made under the presence of water.
Excess water drives the chemical equilibrium towards hydrolysis, and hydrolysis breaks up large
molecules. Building larger molecules require the removal of water from monomers. Miller-Urey
experiments stop at monomers and do not proceed towards larger molecules, because the
chemical equilibrium prefers hydrolysis over dehydration synthesis.
3c. You can remove the water or decrease the amount of water in the experiment and check the
effects of removing water from the experiment.
Essential knowledge 1.D.1: There are several hypotheses about the natural
origin of life on Earth, each with supporting scientific evidence.
LO 1.28 The student is able to evaluate scientific questions based
on hypotheses about the origin of life on Earth. [See SP 3.3]
LO 1.29 The student is able to describe the reasons for revisions
of scientific hypotheses of the origin of life on Earth. [See SP 6.3]
LO 1.30 The student is able to evaluate scientific hypotheses
about the origin of life on Earth. [See SP 6.5]
4. Stromatolites are widely distributed and ancient fossilized artifacts made by the sedimentary
process of rock formation through the activity of microbes. Sediments were trapped by biofilms
of ancient bacteria such as blue-green algae and over generations layers of biofilms were
fossilized, creating the stromatolites. The process of stromatolite formation continues in the
mounds of Shark Bay, Australia. If the time to create these mounds is extrapolated backwards
in time, it can be concluded that the Earth is likely older than any of the times stated in the
hypotheses.
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Emergence of Organic Molecules
Essential knowledge 1.D.1: There are several hypotheses about the natural
origin of life on Earth, each with supporting scientific evidence.
LO 1.30 The student is able to evaluate scientific hypotheses about the origin of life on Earth.
[See SP 6.5]
LO 1.31 The student is able to evaluate the accuracy and legitimacy of data to answer scientific
questions about the origin of life on Earth. [See SP 4.4]
Essential knowledge 1.D.2: Scientific evidence from many different
disciplines supports models of the origin of life.
LO 1.32 The student is able to justify the selection of geological, physical, and chemical data
that reveal early Earth conditions.
[See SP 4.1]
5.
a. RNA chemically evolve. RNA evolved an association with amino acids to produce proteins.
DNA evolved to assume the genetic responsibilities of RNA that led to the evolution of the
first cells.
b. The geochemistry at the ocean and crust interface produces a basic and reducing
environment (serpentinization). Important minerals involve in biochemistry such as Fe, Ni, S,
and P are present under favorable redox states that allow for the reduction of carbon
compounds producing amino acids, sugars, and nucleic bases in compartments defined by
the crystalline structure of the Fe and Ni sulfide.
Essential knowledge 1.D.1: There are several hypotheses about the natural
origin of life on Earth, each with supporting scientific evidence.
LO 1.30 The student is able to evaluate scientific hypotheses about the origin of life on Earth.
[See SP 6.5]
LO 1.31 The student is able to evaluate the accuracy and legitimacy of data to answer scientific
questions about the origin of life on Earth. [See SP 4.4]
Essential knowledge 1.D.2: Scientific evidence from many different
disciplines supports models of the origin of life.
LO 1.32 The student is able to justify the selection of geological, physical, and chemical data
that reveal early Earth conditions.
[See SP 4.1]
www.njctl.org
AP Biology
Emergence of Organic Molecules