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128 Cards in this Set

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The Mars Exploration Rovers were equipped with independent “legs” and wheels to give it ______________ and _______________.
Stability, flexibility
Instead of a hard shell, arthropods invented an __________________ to wear outside their body.
Exoskeleton
The exoskeleton is the most successful innovation that came from the ______________ explosion.
Cambrian
_____________________ were likely to be the fist animals to venture onto land.
Horseshoe crabs
Over ____________ percent of known animal species are insects.
90
Flowering plants are classified as _____________________.
Angiosperms
Flowers house both _______________ and ________________ reproductive organs.
Male, female
Flowers have evolved to use ____________________ as couriers for their pollen.
Animals
Flowers that can be pollinated by a wide variety of insects are ________________.
Generalists
The dead horse arum attracts pollinators by smelling of ___________________.
Rotten flesh
_____________________ is the mutual evolutionary influence between 2 species that become dependent on each other.
Co-evolution
Plants produce _______________ to function as a reward for visiting insects.
Nectar
What is the most important innovation of the arthropod body plan? Explain.
The most important innovation of the arthropod body was the assembly of repetitive, basic body units. The success of this comes from the flexibility of the segments to perform different functions such as forming the head, thorax and abdomen. This design also allows for segments to develop into accessory structures such as appendages, antennae, eyes and wings.
Explain the mechanism arthropods use to protect their bodies.
Arthropods have invented an exoskeleton that they wear outside their body. This is composed of a specialized polysaccharide called chitin. Chitin provides support and points of attachment for muscles and tendons. The ability of the arthropods to join together multiple plates of their exoskeleton offers flexibility and protection. This exoskeleton acts as a suit of armor allowing the arthropod to become the first animal to conquer land.
What are the 3 segments that make up an insect body plan and what does each contain?
Head – Contains the brain, antennae and compound eyes.
Thorax – Contains 3 pairs of legs and 2 pairs of wings (some have no wings).
Abdomen – 11 segments containing excretory and reproductive organs
What are the different parts of the flower reproductive organs?
Flowers are both male and female. The female reproductive organs include the ovule (egg) in the center of the flower surrounded by petals. The ovule is connected to the style which extends upward to form the stigma (landing platform). The male reproductive organ is the stamen. This is composed of a stem (filament) and a structure (anther) that rests on top of it. The anther contains the pollen grains which are the sperm equivalent in animals.
What is the generalist strategy of pollination? Where does this strategy occur most and what are the characteristics of a generalist plant?
The generalist pollination strategy is used by plants whose flowers can be pollinated by a wide variety of insects. This occurs most in the temperate zones where flowers bloom for only a short period of time. These plants produce flowers with highly visible colors such as white, yellow, pink and purple that can be easily detected by pollinating insects. These flowers only bloom at certain times of the year and not all at the same time. This small number of blooms at a time increases the likelihood of cross fertilization of plants in the same species.
How is the bumblebee orchid an example of a plant that uses the specialist pollination strategy?
The members of the bumblebee orchid family have flowers that resemble the abdomen of female bees. Some have iridescent color patterns while some have hairs to resemble those found on a female abdomen and some produce pheromones similar to those used by females to attract males. A male bee will try to mate with the orchid flower bumping its head against the pollinia in the process. The pollinia sticks to the head of the bee like a pair of horns and when the bee attempts to mate with another orchid it unwittingly delivers pollen. Each species mimics only one species of bee or wasp to ensure the pollinia are transferred to the correct flower.
What is co-evolution and how does this relate to plants and insects? What is the difference between the generalist and specialist strategies used for pollination?
Give one example of a generalist plant and one example of a specialist plant and explain what makes it generalist or specialist.
Co-evolution is the mutual evolutionary influence between 2 species that have become dependent on each other. The existence of many insects relies entirely on the plants they pollinate and, similarly, plants rely entirely on specific insects for their reproductive cycle. The extinction of one would inevitably lead to the extinction of the other species. This has produced a mutual relationship which is a form of co-evolution.
A generalist plant is one whose flowers can be pollinated by a wide variety of insects where as a specialist plant uses flowers to attract only a specific species of insects, birds or other animals.
An example of a generalist plant is the balsam plant. This plant produces flowers with highly visible colors easily detected by most pollinating insects. This plant has bell-shaped flowers that produce nectar to attract all types of pollinators and in return deposits and receives pollen from the pollinator.

Bumblebee orchid – flowers that resemble the abdomen of female bees, iridescent color patterns and some with hairs, produce pheromones identical to those produced by females to attract males, males will attempt to mate with the flower bumping its head in the process. This will cause the pollinia to stick to its head and the bee will transfer the pollen to the next flower it visits.
Current data suggest that 2 in 3 Americans is either __________ or ____________.
Obese, Overweight
The BMI represents ___________ __________ ____________.
Body Mass Index
The BMI evaluates your ___________ in relation to your _________.
weight, height
If your BMI is greater than 30 you would be considered _____________
obese
If your BMI is between _______ & ________you would be considered overweight.
25, 29
A calorie is the amount of released heat to raise 1 kg of water by _________.
1*C
If you eat an extra 40-50 calories a day, you would be estimated to gain _____ pound(s) every year.
one
The equation for photosynthesis begins with carbon dioxide, sunlight, and water, to form, glucose, ___________, and water.
oxygen
In plants, the green pigment that traps solar energy is known as __________.
Chlorophyll
source of hydrogen needed for photosynthesis comes from___________
water
Obesity can result in a number of diseases such as heart disease, ___________, high cholesterol, osteoarthritis ___________ and ___________
diabetes, stroke, cancer
The splitting of uranium atoms, as used in the atomic bomb dropped on Hiroshima, is referred to as nuclear _____________.
fission
The process of fusing hydrogen atoms to form helium, which releases huge amounts of energy, is known as __________.
Nuclear fusion
Photosynthesis is one of the most important of biological processes on Earth. Explain the process of photosynthesis in words, describing the components which plants take in and which are produced.
Plants take up carbon dioxide from the atmosphere and water from the soil and use sunlight to split water into hydrogen and oxygen. The hydrogen is then used to join with carbon dioxide in the air to form carbohydrates, with byproducts of water and oxygen.
Describe the strategies that plants have evolved for collecting light and water.
Light: Some plants compete for sunlight by growing into towering trees. Smaller plants beneath the canopy either fail to thrive or simply die. In this way plants compete for light.
Water uptake: Roots have specialized root hairs to ensure that every drop of water is taken up. Through a set of tubing knows as xylem, water is brought to every leaf through the process of transpiration.
We measure energy uptake in humans in terms of calories. Describe how a calorie is measured (include the name of the device used), how a small excess of calories per day can lead to obesity over a lifetime, the statistics of obesity as a cause of death in 2000, and 3 major health consequences of obesity.
Calorie is measured using a Calorimeter as is defined as the amount of heat energy that raises one kg of water by 1C.
As little as 40-50 extra calories a day can cause you to gain about 1 pound per year. Over the course of a lifetime, an individual may gain many pounds to the point of obesity.
In the year 2000, obesity accounted for approximately 400,000 deaths in the United States, second only to smoking-related death.
Any of the following 3: heart diseases, stroke, adult onset diabetes, high cholesterol, osteoarthritis, and certain types of cancer.
How is the energy released from the sun produces and how long will this reaction continue for?
Within the sun, at its core, nuclear fusion is occurring. At a temperature of 28 million degrees, hydrogen atoms are combined to form helium, releasing huge amounts of energy which reach the earth in the form of light and heat. This reaction in the sun has been occurring for 5 billion year and will continue to occur for another 5 billion years.
Explain how energy originates in the sun and how that energy, once it reaches Earth, is transferred through the food chain.
Within the sun’s core, hydrogen atoms are combined to form helium, a process known as nuclear fusion. This process results in the production of huge amounts of energy with radiates from the sun in the form of light. When this light reaches the Earth, plants use it to carry out photosynthesis, the process that converts solar energy into chemical energy in the form of carbohydrates. Animals and insects can then feed on the plants and break down those carbohydrates to provide energy for their own biological processes. Other predators, such as birds and mammals then feed on these intermediary organisms, and utilize the carbohydrates in them as energy for themselves. The energy all organisms obtain ultimately results from the light released from nuclear fusion in the sun.
In ____________, ATP production is very low and there is a buildup of lactic acid as a byproduct.
Anaerobic respiration
In aerobic respiration ________ is broken down in to water and _________.
glucose, CO2
__________ is required for aerobic respiration.
oxygen
In anaerobic respiration glucose is broken down into __________ _________
lactic acid
In the Nazi gas chambers, __________ was used to cause death as this gas which blocks the enzyme that transfers hydrogen to oxygen.
Hydrogen cyanide
Hydrogen cyanide inhibits ________ _________ by blocking the enzyme that transfers hydrogen to oxygen.
aerobic respiration
When you eat food, your body utilizes the __________ within it to make carbon dioxide and water.
glucose
In physical exercise ________ provides the chemical energy to power muscle contractions
ATP
Enzymes accelerate chemical reactions but remain __________ themselves.
unchanged
_________ are proteins that facilitate biochemical reactions
Enzymes
Your body is only a temporary home for hydrogen, oxygen, and _________ atoms
carbon
The French scientist, Antoine Laviosier, developed the Law of ________________to describe the fact that matter cannot be created nor destroyed.
Conservation of Matter
Compare and contrast anaerobic and aerobic respiration.
Aerobic and anaerobic respiration are the processes by which animals make energy from the conversion of carbohydrates into water and carbon dioxide.
Aerobic respiration requires the presence of oxygen to produce ATP. Anaerobic respiration can occur in the absence of oxygen, but only produces 5% of the ATP as aerobic respiration, and can lead to the build-up of lactic acid.
How is aerobic respiration related to photosynthesis?
Respiration and photosynthesis can be thought of as interrelated chemical processes. In photosynthesis, carbon dioxide and water are used to produce energy (carbohydrates) and oxygen. Respiration requires carbohydrates and oxygen to produce energy (stored as ATP) with the byproduct of carbon dioxide.
Describe the Law of Conservation of Matter. Explain how Earth can be considered a closed system and give an example from class/text which illustrate the effect of anthropogenic environmental contamination of human and animal health.
The Law of Conservation of Matter states that matter is neither gain nor lost in a chemical reaction, but that elements are only rearranged with an input or release of energy.
Earth can be considered closed system as most all of the elements here are cycled, and thus man-made chemicals stay in the environment, to be utilized again and again.
In Missouri, it was discovered that men were experiencing low sperm count, which was most likely a result of the inputs of farm chemicals into the local drinking water.
Beluga whales living in the St. Lawrence Seaway were discovered to have a very high cancer rate. These cancers were linked to the interaction of the many chemicals to be found polluting this waterway. Although individually these chemicals may not cause cancer, their interaction could potentially have serious consequences to wildlife including the whales.
What are enzymes and what are their properties?
Enzymes are proteins that have complex structures allowing them to catalyze highly specific biological reactions. Enzymes contain active sites that bind the compounds involved in the chemical reaction, substrates. Enzymes remain unchanged during the chemical reactions even thought they facilitate changes in the substrate. An enzymes function can be affected by inhibitors which prevent the enzyme from binding the substrate normally.
Discuss 2 inhibitors of aerobic respiration. Tell how they inhibit and what is the end result to the organism?
Hydrogen cyanide: Is a competitive inhibitor for one of the enzymes responsible for the transfer of hydrogen to oxygen. It kills the same way as suffocation does.
Carbon monoxcide: this exhaust gas kills by disrupting aerobic respiration. It has the ability to displace oxygen from binding to hemoglobin. It is 200 x stronger affinity to hemoglobin than oxygen. It results in oxygen deprivation killing the organism
In ____________, ATP production is very low and there is a buildup of lactic acid as a byproduct.
Anaerobic respiration
Elevation of the body core temperature to a dangerous and often fatal level is known as __________.
Hyperthermia
The seasons on Earth are a result of the ______ of the axis.
tilt
The _______ is the portion of the Earth measured from the iron core, to the mantle.
Lithosphere
Even though Venus is twice as far from the sun than Mercury, its surface temperature __________ than Mercury and is mostly likely the result of ____________ trapped in its atmosphere.
higher, CO2
The thin layer of air that has been captures and is maintained by Earth’s gravity is known as the __________.
Atmosphere
The Earth’s ________ contains all of the water on the planet, of which the vast majority is in the form of _________.
Hydrosphere, Salt water
The amount of carbon dioxide in the atmosphere on Earth is maintained by the __________, which absorbs it through photosynthesis but produces it as a result of respiration.
biosphere
The _______ greenhouse effect is most associated with human actions stemming from the burning of fossil fuels and which may be causing changes in Earth’s climate.
anthropogenic
Earth’s seasons are due to the _________° tilt of it’s axis in relation to the sun.
23.5
The ________ extends from the crust to the upper most layer of the mantle.
Lithosphere
The hydrosphere consists of all the _________ found on Earth.
water
The ocean accounts for ____________ of Earth’s water
97.25%
The atmosphere of Earth consists of ____________ nitrogen and 21% _________.
78%, oxygen
What is the hydrosphere and what is its composition?
The hydrosphere is all of the water present on Earth. 97.25% of the Earth’s water is in the oceans, 2.05% is captured in glaciers and the polar ice caps. Finally, only 0.7% of the Earth’s water is found in the ground or in the atmosphere, in the form of fresh water.
Briefly explain the structure of the planet Earth from the core to the surface that we live on.
The inner core of Earth consists of mostly solid iron. Around that core is an outer core consisting of liquid iron. The mantle, a liquid of mush plastic-like rock exists around this outer core. Finally, floating atop this liquid like mantle is the Earth’s crust, which is the solid surface that makes up the outer most part of the planet.
Name two ways that your body gets rid of excessive heat and briefly explain each.
You body gets rid of excessive heat through radiation and perspiration. Radiation occurs by heat dissipation through tiny blood vessels close to the surface of your skin. Perspiration cools the body by evaporation of sweat off the surface of the skin. This evaporation cools your body.
Compare and contrast hyperthermia and hypothermia, at what temperature does it occur and what are the consequences if a condition of hyperthermia gets too severe?
Hyperthermia is when our core body temperature rises to dangerous levels. Hyperthermia begins when the body temperature reaches 40ºC at which time the temperature regulating mechanisms begin to breakdown. Once the temperature reaches 41ºC or higher, brain cells begin to die and seizure, coma and even death can result.
Hypothermia is when the body’s core temperature drops to dangerously low levels. When the core temperature reaches 32ºC shivering and tremors lead to accelerated and irregular heart beat. Finally, organs begin to shut down, brain damage occurs and death results if the core temp drops below 27ºC.
What human characteristics demonstrate that we are adapted to a tropical climate? How were humans able to spread out and survive in non-tropical climates?
The fact that humans have very little hair, along with the fact that we remove body heat very efficiently through sweating indicate that we are most well adapted for tropical environments. It was not until humans developed the usage of fire for heat and clothing for maintaining body heat in cold temperatures that humans were able to move out from tropical climates.
Explain the evidence for global warming seen in the climate changes involving the Saharan dust storms and the North Atlantic Oscillation and how the implications of these changes are worldwide.
Because of extreme drought in Africa, lakes such as Lake Chad have begun to shrink and provide extra sand and dust to be blown into the atmosphere as a result of dust storms that are continuously increasing in intensity. As a result of global warming, the North Atlantic Oscillation, which is the air current that can carry dust and airborne particulate matter to the Americas across the Atlantic ocean from Africa, has become more regular and more intense. Because of this, more and more dust and other debris are reaching the Americas from Africa. This is causing problems in the Caribbean because the spores of a fungus, known as Aspergillus, have been carried there from Africa. These spores are not only damaging coral reefs in the area but also causing a marked increase in the occurrence of asthma in children, demonstrating the far reaching and unexpected negative effects of global warming.
The ______ hypothesis states that the extinction of the dinosaurs was facilitated by a large _______ hitting Earth.
A very accurate way to date living and non-living material using the predicted decay of certain elements is called __________.
The element _________ is often used for dating very old objects like the Earth, because it has a half-life of over 4.5 billion years.
uranium
The _______ is a part of Earth’s history when the planet was constantly bombarded with meteors and the surface was liquid rock.
magma ocean
The ______ catastrophe occurred when the heavy elements sunk to the core of early Earth.
iron
The magnetic field of Earth protects us against the ________ which is radiation given off by our sun.
solar wind
The collision between Earth and a Mar’s sized planetoid created our ______.
moon
Two sources of the water on our planet are likely from ________ and ________.
volcanoes, comets
Early life on Earth is hypothesized to be similar to life surrounding _________ in the deep oceans, where energy from hydrogen sulfide is used.
hydrothermal vents
The amount of oxygen in our current atmosphere is a result of billions of years of photosynthesis by ___________.
cynanobacteria
Evidence suggests that Earth and the ___________ ___________ were formed at the same time.
Solar System
In radiometric dating scientists determine the amount of time required for _____ of the radioactive element to be converted into product.
1/2
___________ has a ½ life of 5703 years, which makes it suitable to date ________ samples.
Carbon-14, young
Earth’s liquid iron core flows and rotates gave rise to the ___________ _________, which protects us from solar winds.
magnetic field/ or electro-magnetic shield
The first life on Earth lived in a very hostile environment, where bacteria survived only deep below the surface by extracting chemical energy from ______________ ____________
hydrogen sulfide
The cooling of Earth’s crust occurred ____________ in earth’s formation.
Early
The atmosphere on Earth reached _________ oxygen about 560million years ago
21%
Briefly discuss 3 major events that took place BEFORE the development of life on Earth. For each event, give some details about what took place and any ramifications for life.
Iron catastrophe: The surface temperature of the early Earth reached very high temperatures from meteoroid and asteroid bombardment and the radioactive decay of rocks. The surface of the Earth was filled with magma, and the heavy elements, such as iron, sank in the magma ocean to form the iron core of the Earth. This liquid iron core flows and rotates to generate the magnetic field that forms the north and south poles. Without this magnetic field, life would not be possible on Earth. This magnetic field acts as a shield to deflect the solar wind, protecting life from large doses of radiation.
Moon formation: The hypothesized formation of the moon states that a collision between a Mars-sized plant and Earth resulted in the formation of our moon. The impact of the collision was so large as to cause the axis of the Earth to tilt, causing the seasons on our planet. This collision is of obvious importance to Earth’s climates and seasons and to the diversity of life that exists due to these seasonal variations.
Ocean formation: All the water on the planet formed after the planet cooled. The water came from two likely sources, Earth’s volcanoes and from liquid water is comets. Volcanoes produce steam (water vapor) when they erupt. When the Earth was young, it was regularly bombarded by comets. The ice in the comet’s tails would have melted upon contact with the Earth and could have contributed significantly to Earth’s liquid environment.
Describe where the oxygen came from in our atmosphere and give 2 pieces of evidence for this process. How long did this process take?
By producing oxygen as a byproduct of photosynthesis, early bacteria caused a buildup of oxygen in the atmosphere, which allowed for the evolution of complex plants and animals. The modern day equivalents of these ancient life forms are the blue-green bacteria or cynanobacteria.
The photosynthetic microorganisms coated the surface of rocks in shallow bays, and they secreted a layer of sticky substance to use as protection against ultraviolet radiation. When sediments infiltrated into the layer, the microorganisms migrated to the surface. As this process occurred over hundreds of years, rock-like structures, known as stromatolites, were formed. These stomatolites can be found as fossils, suggesting they were responsible for the oxygenation of the atmosphere.
Iron oxide (or iron ore), which is mined today for steel production, is a byproduct of the oxygenation of the planet. It took about 1.5 billion years of continuing accumulation of atmospheric oxygen to reach the current atmosphere oxygen concentration of 21%.
This process took about 1.5 billion years to raise oxygen levels from about 1% to the current 21%
When the Apollo astronauts brought back moon rock samples they were surprised to find that the composition was very similar to the rocks found on Earth. Describe the hypothesis that the scientists come up with to explain how the moon was formed, discuss its importance to the formation of climate and seasons, and discuss why the moon rocks were similar in composition to Earth’s.
Hypothesis: Moon was formed by a collision between early Earth and another small planet. The collision destroyed the other planet and removed a significant proportion of Earth. The debris that was strewn into space eventually coalesced and formed the moon.
The force of the impact caused the Earth axis to be tilted 23*. This tilt gives rise to the seasons and climate found on Earth.
Since some of the debris were of Earth’s origin that it is not surprising that the composition of the rocks on the moon are very similar to that of Earth’s.
The technique called _____ fertilization has been used for about 30 years to assist couples who have had difficult conceiving a child on their own.
in vitro
In vitro fertilization is when the ________ is fertilized outside of the ___________.
egg,uterus
The _______ experiment was conducted by a graduate student in 1953 who demonstrated that the early Earth could have produced compounds, like amino acids, necessary for life.
Miller
The collision of _______ with Earth has been shown to cause the formation of peptides, the chemicals which make up proteins.
comets
Three basic characteristics of life include the abilities to ______, ______, and _______.
use energy, reproduce, evolve
The formation of _______ , which surround all cells and act as a container for life, has been accomplished by scientists interested in the formation of early life on Earth.
membranes
Once all elements in the center of a star have been utilized for energy, the star reaches the ______ barrier.
iron
In order for heavy elements to be produced, a star must ______, which generates tremendous heat allowing for the formation of many of the elements found I the universe.
explode
A ________ can be made by stringing together the correct sequence of nucleotides together.
gene
The 3 requirements of life include energy for growth and change, to___________, & to___________
reproduce, evolve (in either blank
Stars are formed by the fusion of 3 ________ nuclei to produce carbon.
helium
A star explosion, know as a ____________ __________, occurs when ________ cannot be fused further.
super nova, iron
All of the hydrogen, carbon, oxygen, nitrogen, calcium, and iron in our body come from _________ _________ that was released by stars upon their death.
star dust
Living organisms are composed of 49%___________, 24%__________, and 24% oxygen.
hydrogen, carbon
The theory that life arose on Earth from organic building blocks that were present in the water on Earth’s surface is known as the __________ hypothesis.
Abiogenesis
In her experiments, Jennifer Black demonstrated that the intense heat and pressures meteorites experience during entry into earth’s atmosphere actually causes amino acids in a meteorite to form __________.
Polypeptides
Energy powers life through the inter-conversion of water and carbon dioxide to form __________.
Carbohydrates
All the elements in the Periodic Table are formed in the star. Briefly describe the steps in the process of creating these elements.
1.Stars obtain its energy by the fusion of hydrogen to form helium
2.As hydrogen is gradually exhausted, helium is fused to form carbon, oxygen, nitrogen, and other heavier elements
3.When iron is formed, the star has no more fuel to burn and begins to die
4.The dying star first collapses before turning into a super nova and explodes
5.The energy of the super nova breaks through the iron barrier to form the remaining elements in the periodic table
In 1978 the first “test tube” baby was born and since then, in vitro fertilization (IVF) has become a mainstream procedure. Explain how IVF works in detail. Discuss 2 reasons why this procedure was so important.
A) First the female’s ovaries are stimulated by hormones, which causes the release of multiple eggs. The eggs are then collected using an ultrasonic needle that pierces the vaginal wall. Each egg is then incubated in a Petri dish with growth media in a ratio of 1:75,000 sperm cells that have been collected from the male. Once fertilized the zygote begins to divide. In 3 days they become tiny embryos consisting of 6-8 cells and are ready to be transferred to the female’s uterus.
B) It demonstrates how human life originates and provides an example to how nature can be manipulated by technology.
What is the general chemical composition of living organisms?
The primary elements that make up living organisms are hydrogen, oxygen and carbon, combining for 75 percent of all atoms. Other elements such as nitrogen, phosphorus and sulfur are also found in living organisms. These elemental concentrations vary from the compositions of both the Earth itself and from the compositions of the universe as a whole.
What is the evidence in support of the Big Bang?
A first line of evidence came from Edwin Hubble who noticed that galaxies are moving away from one another at very rapid speed. This would correspond with a small point of mass and energy exploding all of the matter is still moving away from that point. Einstein’s E=mc2 also supports the theory. This equation allows for a very small point to contain huge amounts of mass and energy, which could be released in a Big Bang like event.
Name three sources of organic material from space that have contributed to the building blocks of life on Earth. For each, name the kinds of material that could be contributed.
Meteorites: The chemical compositions of some meteorites are rich in organic materials, including 70 different kinds of amino acids. This finding raised the possibility that during the heavy bombardment of the infant Earth, meteorites, comets, and asteroids played a significant role in filling the Earth’s surface with the organic building blocks that are necessary for life.
Start dust: In addition large objects, Earth is showered with small specks of meteorites measuring less than 1 mm wide. This idea suggests that the delivery of organic compounds from space has occurred throughout the entire history of the Earth. This material is a rich mixture of organic compounds.
Comets: The collision of meteorite impact with the Earth could lead to the formation of organic compounds. These collisions could produce amino acids and complex peptides, which when joined together form proteins.
The inhospitable caves known as Caeva De Willa Luiz in Mexico are home to bacteria which form large colonies that drip from the ceilings. These colonies are called _________.
snottities
Lake Vostok is a large body of water which is located about 4,000 m below the ___________ ice sheets and contains abundant life which can tolerate the extreme cold.
Antarctic
Bacteria live 3.5 km underground within the Earth’s crust and gain their energy from _______ gas.
methane
______, a moon of Jupiter, is hypothesized to have a liquid ocean capable of supporting life under its thick ice caps.
Europa
SETI was the first scientific organization to look for evidence of ______________
Extraterrestrial Intelligence
The equation formulated in the 1960’s to estimate the possible number of intelligent civilizations in the Milky Way Galaxy is called the _______ equation.
Drake
Although it is currently impossible to see distant planets around other stars using telescopes, we can detect them because the planets exert a gravitational pull on the stars that they orbit. This pull causes the star to _________.
wobble
________ telescopes were the first type of telescopes employed to look for the signals of communication from distant civilizations.
Radio
One argument for the presence of intelligent life elsewhere in our galaxy assumes that because _________ evolved, the conditions of the universe must be suitable for intelligent life to evolve elsewhere.
humans
How are other planets located?
Most astronomers are convinced that planets similar to those found in our solar system must exist in other stars but finding them is difficult. Planets outside our solar system are difficult to see due to the luminosity of the starts. Two astronomers have developed a way to determine the presence of a planet by measuring its gravitational pull on its star. This pull causes the star to wobble. This wobble can be determined by measuring the shifts in the wavelengths of the light that is emitted by the wobbling star. This is known as the Doppler Effect. Many planets have been discovered using this method, most of them similar to Jupiter and Saturn.
Name the 4 extreme Earth environments detailed in class. For each, briefly describe the conditions found there and types of organisms present. What do these environments tell us about the possibility of life on other planets?
1. Cueva De Villa Luiz, 2. Lake Vostok, 3. South African mine, 4. Cold Seep
1. The bacteria use the hydrogen sulfide gas as a source of energy, and sulfuric acid is produced as a by-product, making the cave environment inhospitable for other organisms. These bacteria form mucous colonies, known as snottities, hanging from the ceiling and walls of the caves.
2. These lakes are warmed by the geothermal heat produced in Earth’s mantle. Evidence of life is abundant and is rich in simple life forms. Because the glaciers above the lake were formed millions of years ago, the lake water could be as old as one million years.
3. The microorganisms present obtain their carbon source from carbonaceous materials present in the rock and they rely on methane gas that seeps from the Earth’s crust for energy.
4. This entire ecosystem of clams, tubeworms, shrimps, and other organisms is supported by bacteria that obtain energy from methane gas that seeps from the Earth’s crust. The bacteria form symbiotic relationships with clams and tubeworms. Together, they develop an extensive food web of predators and preys.

These four examples demonstrate that environmental conditions that are hostile to us (ph, pressure, temperature, energy) can still support life, as long as the basic requirements of energy, carbon source, and water are fulfilled. Based on these examples, there are many places in the solar system that might be able to support life.
Name the two arguments that suggest intelligent life does exist somewhere in our galaxy? Describe what each argument suggests.
Argument of scale, Anthropic argument.
The argument by scale is based the fact that there are billions of galaxies, each with billions of stars, and potential Earth-like planets). The chemistry of life is based on the most abundant elements in the universe. Because the Earth is governed by the same laws, chances, and effects, it occupies no special place in the universe). The vast universal scales of time and space make even very small probabilities of any one planet producing intelligent life an almost certainty.
The anthropic argument suggests that because humans have evolved into an intelligent civilization, then the conditions of the universe must be suitable to evolve life which can ultimately become intelligent. If intelligent life has evolved on Earth, it should and must evolve in other planets of this vast universe.
Why do some scientist believe that life extraterrestrial life will never be found?
What is the fundamental argument for this belief and what does it have to do with the evolution of intelligence on Earth? Even if intelligent life did evolve somewhere else, what process is likely to affect its survival. What barrier exists to preclude us from communicating with extraterrestrial life if we find it?
Some scientists think extraterrestrial life will never be found, because it does not exist.
Their arguments point toward the unlikely development of intelligent life on Earth.
Time is the most important factor in the evolution of intelligent life. Unicellular life dominated the planets over 90% of its geological time. Anatomically modern humans (humans like you and me) emerged from Africa about 200,000 years ago. Human civilization began about 10,000 years ago, and science did not become a way of acquiring knowledge until about 500 years ago. It was only in the last 100 years that science and modern technology have propelled our human society into a technologically extraterrestrial life.
Self-annihilation in a technologically-advanced civilization is highly probable.
Also, even if ETI does exist, our ability to communicate with them over vast periods of time and space will be extremely difficult. These difficulties can only be overcome if we invent time travel.