Unit 1: Evolution Study Guide PDF

Table of Contents Unit 1: Evolution Unit 1 Study Guide January 9th, 2025 Formation of the Elements in Stars: Stanley Miller’s Forgotten Experiments, Analyzed: The RNA Enigma: Grand Challenge: Permeability of the Membrane January 13, 2025 Transiting Exoplanet Survey Satellite (TESS) Life On Other Planets Emergence- How Stupid things become Smart together Are Viruses Alive? January 16, 2025 What Earth’s Early Endosymbiotic Theory Photosynthesis Snowball Earth Cambrian Explosion January 23, 2025 Finding Tiktaalik: Neil Shubin Darwin's Dilemma - solving the riddle of the Cambrian Explosion Overproduction of Offspring - Crabs Mechanisms of Natural Selection January 27 2025 Galapagos Finch Evolution Video stuck on slide 13 Sexual Selection Founder Effect, Bottle Necking, and Genetic Drift What is a species Evolution in Action: Ring Species January 30 2025 How Many Mass Extinctions Have There Been Homologous Structures vs Analogous Structures Unit 1: Evolution Unit 1 Study Guide January 9th, 2025 56q Formation of the Elements in Stars: Video Link: The Elements: Forged in Stars Everything besides hydrogen and helium are forged by stars through fusion ○ Fuses hydrogen, helium, carbon, and it goes down the line until it hits iron and runs out of fuel Causes supernova and creates everything beyond iron Due to the intense heat and pressure of a star’s core, nuclear fusion causes hydrogen to form helium, this process continues, combining elements together to form newer ones. ○ Iron is the endpoint of nuclear fusion, stars die when accumulating too much iron, causing a supernova. ○ The energy of a supernova turns Iron into the remaining elements. Stars begin their life with hydrogen and helium. The pressure is so high that the hydrogen forms helium. Eventually the star runs out of hydrogen. Helium can form carbon and then from there they can form oxygen and nitrogen. These are the principal elements of life. ○ From there the rest of the elements are formed faster and faster and faster. Until it reaches iron. From there no more fuel can be used and the star dies, expanding and exploding creating a supernova. In a supernova a lot of energy is released cooking up heavier elements because the iron barrier is broken. When a star builds up too much iron, it dies. Stanley Miller’s Forgotten Experiments, Analyzed: Video Link: Stanley Miller's Forgotten Experiments, Analyzed The experiment was published in 1953. The spark represents lightning. The liquid water represents the oceans. The methane and ammonia gas represents what was thought to be the early Earth’s atmosphere. Not only does this form amino acids. but through adding an external compound called cyanamide you can create peptides (A chain of amino acids). The RNA Enigma: Grand Challenge: Video Link: The RNA Enigma DNA is a double stranded heliotype RNA is also a nucleotide but is single stranded ○ switch genes on or off ○ store genetic information ○ Functions by folding up into shapes shape determines functions So many possible shapes, computers don’t have much luck finding custom RNA folding usages, like stopping cancer RNA are versatile cellular machines that can do both what DNA and proteins do. RNA forms into shapes, and their shapes determine their functions. If we can determine their shape, we can determine their function. Link to the RNA Lab Permeability of the Membrane Single nucleotides of RNA are able to permeate fatty acid membranes. The RNA interacts with the fatty acids and the fatty acids carry the RNA along into the membrane. Creating Artificial Life Video Link: Creating Artificial Life In 2010 scientists were able to create mycoplasma which was able to 1,000,000 base pairs and DNA. However, this wasn’t really completely artificial. The scientists had to take a cell membrane (a mycoplasma cell membrane) and place in their own genome inside. They placed in their own watermarks and required help from E.Coli and yeast to pair the base pairs. January 13, 2025 Transiting Exoplanet Survey Satellite (TESS) Video: Transiting Exoplanet Survey Satellite (TESS) 2018 Has four cameras and sends the data every 2 weeks (10 billion pixels) The raw data goes through a 5 step process The change of a star’s brightness could be the cause of many things Can be sent for follow up observation Life On Other Planets Comets helped fill the ocean when they crashed into Earth but it is also possible that comets brought the building blocks of life to the Earth as well. Comets can bring the seeds and the fertilizer of life to a planet. If life here is related to comets bringing the building blocks of life to Earth, it could have possibly happened elsewhere in the cosmos. 60 light years away, scientists have observed a large amount of comet dust revolving around a star. If comets could not only deliver organic compounds but other living organisms. The greatest challenge any life could face on Ganymede, is the large ice sheet that covers the world. We could encounter life in Ganymede within the next decade. A bunch of comets land on a planet, bringing not just water but also organic compounds, and that impact fuses together some organics to cook up something maybe a little bit more, if comments are the seeds to life it is much more likely there is life everywhere else in the cosmos… “Panspermia hypothesis”: The theory that life originated in space and spread to other planets, including Earth, via comets, asteroids, meteoroids, and space dust. Icy moons of jupiter could harbor life Maybe comments can deliver living organisms? “If there is water how can there not be life” Ganymede has a lot of ice so the ice on top of the water is blocking the sun, so we should check the bottom of the ocean where the sea vents are and maybe we will find life Due to Ganymede’s oceans, it may be possible for life to form. Emergence- How Stupid things become Smart together Complexity arising from simplicity. Interacting among a set of rules to rise beyond themselves. Producing order through chaos. Emergence is what causes stupid things to be smart together. The idea describes small things forming bigger things that have different properties from the sum of its parts. Water has vastly different properties than the molecules that make it up. Wetness is once of them. Many things interact under a certain set of rules, creating something above and beyond themselves. More is different which in itself is a new thing. Like layers stacked upon each other that have different properties. This is only possible through following a ruleset that produces order through chaos. While we don’t have a definition of what living things are, we know that they come from things that are not alive. Emergence the way stupid things become smart together, small things form bigger things greater than the sum of its parts. It is complexity arising from simplicity. Wetness is an emergent property of water. Following a rule set that is producing order through chaos Are Viruses Alive? Link: 5 Intriguing Facts About Viruses | UCLA Health Viruses don’t have to find food or metabolize. If they don’t have a host, they’re quite dormant. Viruses require hosts to stay “alive”, requiring the host cell to provide the food and energy for it to reproduce. Viruses survive better than we do because they evolve more quickly than we do. Viruses are simpler than other living things, able to be created through the purified components. Protein and Nucleic Acid. They are also very symmetrical. Viruses hijack living hosts, unable to reproduce. It does respond. Fastest Evolving “Organism”, goes through heredity due to reproduction, rapidly copies itself. Can be made from scratch. Considered physically beautiful, symmetrical along axes. Viruses don't need to metabolize food and thus are considered not alive, They hijack living hosts, they are parasites, they steal energy Viruses goes through evolution extremely quickly, by going through many generations and thousands of copies in one hour are made from one copy Viruses are very pretty it has very high symmetry it has a certain number of axis January 16, 2025 What Earth’s Early In a process called differentiation, Earth separated into layers. The Earth started about 4.5 years ago. The Hadean Eon: 4.5 to 3.8 Billion Years Ago. The first early stage of the earth. The Archean Eon: 3.8 to 2.5 Billion Years Ago. There were oceans, banks and rivers during this time. Around 3.5 billion years ago stromatolites formed. 2.8 billion years ago bacteria were able to evolve and be able to use photosynthesis, releasing oxygen. The Great Oxidation Event: 2.8 Billion Years Ago. Oxygen caused a catastrophic event for some organisms while it caused others to thrive. Snowball Earths: 2.4 Billion Years Ago to 650 Million Years Ago: There was mass glaciation that happened multiple times The Phanerozoic Eon: 542 Million Years Ago: Extensive forests covered the earth and enabled an even greater influence on life. Endosymbiotic Theory Scientific Theory is not an educated guess: It is an explanation of an event supported by scientific evidence. It must be testable and tested over and over again. Prokaryotes (Pro rhymes with No) have no nucleus and Both types of cells have cell membranes, cytoplasm All bacteria are prokaryotes It is said that larger prokaryotes consumed smaller bacteria that might have been able to convert ATP into energy or convert sunlight to energy, forming early forms of eukaryotic cells. The evidence for this theory is that the size of the mitochondria and chloroplasts are similar in size to bacteria, they divide in the same way that bacteria do, and they have a similar structure to other prokaryotes. Photosynthesis - The formula for photosynthesis → Solar energy + 6 CO2 + 6 H2O → C6H12O6 + 6 O2 - Thylakoid membranes pull in light and releases ATP - The Calvin cycle takes in the NADPH, ATP, and CO2 to create carbohydrates or the sugars. - During photosynthesis, plants take in water, carbon dioxide and solar energy to produce carbohydrates in the chloroplast, or more specifically, the thylakoid membrane. Snowball Earth The orbit around the Earth was unstable and while the Earth is far away and tilted away from the sun the Earth cools heavily. Cyanobacteria started producing oxygen which destroyed the greenhouse effect and methane. Temperatures fall and create ice, sunlight bounces off of the ice causing the temperature to fall and it keeps going. Life was barely able to hang on due to volcanoes that punched through the ice and helped warm the Earth. 3:49 Cambrian Explosion Increasing oxygen levels ○ Prior, oxygen levels was too low for large animals to survive ○ Snowball Earth ○ Erosion, calcium, silicon Increasing mineral availability ○ Shells –calcium Evolutionary innovation ○ Feedback cycle of innovation between predators and prey evolving quickly to survive Emergence of vision Recovery from mass extinction (possibly) January 23, 2025 Finding Tiktaalik: Neil Shubin - This was their last expedition and they were running out of money - They were cracking rocks and found a flat headed fish aka the Tikaalik - He tried to find rocks in the world that had the right properties to have fossils - So he looked around the road and it became clear the best and most unexplored place in the world was the canadian arctic - It is the perfect fossil to show how we went from water to land - Around 360-375 MYA we got on land Darwin's Dilemma - solving the riddle of the Cambrian Explosion - Why do we not find fossilized ancestors of the cambrian fauna - Darwin's Dilemma was that he couldn't find the fossils of the animals in the cambrian - Prominent features of the cambrian explosion, Abruptness and Exceptionality - Lack of a fossil record because a lot of the material before 542 isn't available at the surface so we dont have alot of material to go looking at it - The conditions were not suitable to preserve the organisms?? - There is a lot of evidence that shows there are probably those organisms that we can't find the fossils of, maybe it wasn't an explosion but a gradual pickup Overproduction of Offspring - Crabs - There are a bunch of crabs going down near the sea, probably 120 million, all the adult females among them have chosen this time for their annual reproduction - A single crab is carrying about 100,000 eggs, she herself is a land crab and she cant swim but the eggs need to be released in the sea to survive - When at length she does reach the sea she releases the eggs while trying to not get swept away - The eggs turn the water into a black soup because their are so many eggs Mechanisms of Natural Selection DNA made up of genes which have multiple alleles which determines phenotype Recombination and mutation create a random mix of traits and characteristics of the parents January 27 2025 Galapagos Finch Evolution - The basic idea is beaks are tools and you need the right tool for the right job - Darwin initially mistook each finch for a different type of bird, b/c they looked so different - There are 13-14 different species of birds - So a whole bunch of birds could have came in at once and were just there - Or it could be 1 group of birds come out make a living and start to dissociate from their own and having different gene pools aska different species - From careful analysis DNA, none of them are more close to a bird on land than each other, so there was only 1 times birds got there from a single common ancestor - The island is called Daphne Major - They would net the bird's weight, size, and beak size. And even labeled them with tags. Video stuck on slide 13 - Moths and bats are stuck in a co evolution, moths are pray bats are predators - Moths evolved a counter weapon an ear to detect sonar so it could know if a bat is coming and can try to dodge - Long ear bats evolved better ears to be able to hear the moth if they moves without the need of sonar just by hearing them, they will still use sonar to doge trees but turn it off when attacking or near moth - Each newt contains enough poison to kill 20,000 mice or a bunch of ppl. Local animals knows newts are deadly and crows and mice are not the problem. - Gardner snacks are the prey, they try to eat the newts so every generation the snakes get more resistant and the newts more poisonous. The snakes skin if they do eat the newts then gets saturated with the poison and interestingly these snakes have more color perchance to show off their second hand poison Sexual Selection - Darwin had a real problem with peacocks, sayings the sight makes him sick as he cannot understand why they exist - Well to have these tails, they are heavy and take a lot of nutrients to grow - But same goes for the blue feet of bobbies or the colors of a butterfly - Why is it in nature you can see differences in males in females, such as antlers of male and big body size for females. - This is because of sexual selection, the ornaments are to advertise the animals fitness - Males have competition and females have choice - Males expend no energy to reproduce, the female puts in a lot of energy to reproduce is a lot and requires some competition, and the female is like well which one of these males really have good genes because I want my offspring to be able to live - They found if you were mated with a male with large fans the offspring lasted a lot longer than the females mating with males with smaller fans - Sexual selection is not only physical but is behavioral Founder Effect, Bottle Necking, and Genetic Drift - A small population of humans arrive on an island some without hair some with. Then they procreate on the island and as procreation continues they notice the continuously high number of them that have no hai. - The gene pool is different then the source population (A higher percentage of bald) - Then a huge thing happens and a bunch of the population die resulting in bottle necking - Bottlenecking A portion of the population is randomly eliminated resulting in a population that reflects the genetics of the survivors What is a species - A particular species always gives birth to the same species, dogs can bread with other dogs but never give a cat. - Male donkey can mate with horse and make a mule, but the mule can not reproduce and is a dead end - But there is a thing called ring species where its like —-----------> - What is a species for bacteria as a gold standard - 70% of ACGs need to match - 95% of what it transcribes need to be identical - There is things that look the same - The concept of a species is a human construct and doesn't really fit reality, it's useful but its got no real good definition Evolution in Action: Ring Species - Salamanders despite their differences in looks are all the same species and are freely bred with each population besides one pair. (Yellow Blotch, monterey) - An ancestor came down along the valley and when they reach around the valley the end points cant mate however they still are the same species this is called Parapatric species or ring species - - The January 30 2025 How Many Mass Extinctions Have There Been - We cant just tally the number of species and take the result as the final answer because the fossil record is incomplete and we have less rock for older times and more rock for newer - So now they do some match to account for this and there appears to be 8 mass extinctions - But you could also see 11 there - The first of the big five removed 80% of the stuff on the tree but a lot of the bug branches still were there (Late ordovician) - However some other extinctions have a big limb fall off the tree (Late cretaceous) and because that big branch was removed it creates a lot of space for niche animals to come and grow Homologous Structures vs Analogous Structures - Homologous Structures: - Similar structure - Differing Function - From a common ancestor - Analogous Structures: - Differing structure - Similar Function - Not From common ancestor Human Evolution NEED TO KNOW FOR EXAM: (First one aka lucy!) Facts about Human Evolution (WILL BE ON EXAM) - We believe humans came out of africa in two waves - Homo sapiens BIPEDALISM, apes started walking upright on two feet - Lucy is (3.2) MYA and was one of the first Australopithecus afarensis - We also found fossilized footprints of her buddies - BIPEDALISM is good because it free up two limbs aka our hands - Which they can use to grip and use tools etc LUCY - They have around 400 Australopithecus afarensis now lucy was an adult female but she was around 11-12 years old when she died, - and she stood fully upright they know this because they found her pelvis, and her knee and ankle they found - Then come HOMO Habilis - Aka the handyman (2.1-1.5 MYA) - We have his loot, aka tools - He ate meat which is new and acquired more hands - Eating meat kick started the process of encephalization, due to this we had growth of the brain - First to cook food some say - Temporal lobes grew disportionately due to the other parts of their brian grew big - Then Came Homo Erectus (~2MYA - 143,000 years ago, he was around “Forever”) - First early human fossils found outside africa - Might have been the first to make sea voyages - Homo Sapiens Neanderthalensis (~200,000 years ago - 40,000 years ago) - A separate species we are/were interbreeding with - We have their loot brags, making instruments have beads and jewelry - Have the genes for speaking and chit chat - Close analysis reveals Neanderthals and some modern humans did interbreed - 2019 - Neanderthal DNA in modern human genomes is not silent and is associated with many phenotypic determinations, including skin color and immunity - Neadethals and modern humans hung out with us for around 30,000 years - We shared cultural habits like burying the dead, art, and they had sex - In 2004 they found habits of HOMO FLORESIENSIS aka a hobit - There were like 6 different kinds of humans 100,000 years ago Ancient Humans & Neanderthals Had Sex, Here's How It Changed Us Forever - Those who have higher genomes similar to neanderthals and realized that they are more likely to have addictions, cigarets etc - They realized that if you have higher neanderthals genes, you have hypercoagulability of blood - The genes may have made our skin toughen - decrease schizophrenia and tolerate lower oxygen levels Big Five Mass Extinctions: Late Ordovician: - It killed 80% of the species on Earth but life continued because the big branches of the evolutionary tree were still intact. Late Devonian Late Permian Late Triassic Late Cretaceous: - Trimmed the evolutionary tree by taking a part of it out so the base of it still survived Fossil Records are incomplete How and what happened? Some extinctions alter different parts of the evolutionary tree in various ways. Cretaceous-Tertiary Extinction: K-T - Iridium is more common in asteroids and meteors - Iridium layer at K-T boundary around 56 million years ago separates the age of reptiles & age of mammals Why adaptive radiations after mass extinctions? - Mass extinctions leave many niches unoccupied by competitors - New sources of energy/ways of living are now available to the species that survived - The increase in competition that arises from speciation promotes adaptations to diverge into new niches. At the early stages of embryogenesis, the embryos have similar morphologies and look the same Homologous Structures: - Similar structure - Differing function - From a common ancestor Analogous structure: - Differing structure - Similar function Molecular Commonalities Among Cells: - Energy molecule - Adenosine Triphosphate (ATP) - Information molecule - Deoxyribonucleic Acid (DNA) - Amino Acid Structure: - L (Amino Acids) - Catalytic - Activity Protein - Eukaryotic Cell Division - Mitosis and Meiosis - Molecular Biochemistry: - Amino Acid Sequences of Proteins: - Beta Hemoglobin Differences: - When the numbers of differences are similar, the pairs of organisms are likely to have shared a common ancestor at about the same time in the past. - Primates: - Evolved around 75-80 million years ago - 233 species in 13 families - Most arboreal and tropical - Primate Traits: - Grasping Hand - Grip branches - Grip objects/prey more powerfully - Grasp objects/prey more precisely - Fashion and use tools - Binocular Vision - Depth perception - Human FOV → 120 degrees - Excellent focus - Peripheral Field → 160 degrees - Large Brain - Sensory Input, Acute visual system - Motor output - Social interactions - Learning, memory, info gathering - Parental Care and Sociality - Evolution of Primates Timeline: - 85 MYA —--- Earliest common ancestor - 80-75 MYA —--- Evolution of early primates - 65 MYA ---- Extinction of dinosaurs - 65-45 MYA ---- Adaptive radiation of primates - 47 MYA ---- Ida fossil discovered. Primate/Homind evolution - 30 MYA---- Early primates leading to Old World species - Discovered 2006 in Egypt - Size of a house cat - Small brain - Sexual dimorphism – morphology, size, ornamentation & behavior Human evolution: Reconstruction of the timeline of some of Our Relatives - Multiregional Hypothesis: - proposes that modern humans evolved in multiple regions around the world simultaneously from earlier hominid populations, with significant gene flow between them Anatomically modern humans: - suggests that modern humans originated solely in Africa and then migrated out, largely replacing existing populations in other regions Bipedalism: - Ability to walk on two legs Australopithecus Afarensis: - Lucy - Female - Fully Upright - Adult because wisdom teeth erupted - 11-12 years old Homo Habilis (aka handyman): - Using tools - First human-like hominin - Ate meat - Probably the first human ancestors to cook food - Nutrition improved - Encephalization: Growth of the brain in relation to the overall body mass Homo Erectus: Homo Sapiens Neanderthalensis: - Exhibited care of others - altruism - Buried their dead - Made sophisticated stone tools, instruments, jewelry - Most likely had a spoken language - Our cousin, separate species - Influence skin, depression, addiction, immune system - Genes affected keratin production - Timeline for evolution on land: - Tiktaalik was a transitional species that has characteristics between fish and land animals on Ellesmere Island - Early Theories of Evolution: - Malthus (1798): - Many more individuals are born compared to those that survive. - Erasmus Darwin (1800): states that all life derived from one original ancestor but there is no evidence to back up his point - Lamarck (1809): - States that all changes in the organic as well as the inorganic world are the result of natural laws, not miraculous interposition - Not fully correct - Alfred Russel Wallace (1858): - Any variety having slightly increasing powers of preserving existence will inevitably acquire a superiority in numbers. - Co-discoverer of evolution by natural selection with Darwin - Charles Darwin: - Sketched an evolutionary tree showing the relationship between living species and their ancestors. - Mystery of Mysteries Question: What was the mechanism for how speciation occurred? - Favorable variations tend to be preserved while unfavorable ones are destroyed. - Survival of the Fittest or Natural Selection - Darwin’s Dilemma: - - Mechanisms for Natural Selection (How survival of the fittest works): - Overproduction of offspring - Struggle for existence - Differential survival & reproduction - Organisms that adapt well to the environment can survive and reproduce. - Heredity / Genetic Variation - Species: A community that can produce offspring with one another and the offspring also having the ability to make offspring. - Variations in traits invariably cause differences in the ability of individuals to survive and reproduce. - DNA is made up of genes - Genes have different alleles, which are variations - Genes encode the information used to generate the phenotype and are heritable - Phenotype: Observable Characteristics - Gametes are sperm and egg cells - Many continuous biological traits are normally distributed. - Traits are determined by the additive effects of many genes each having a small positive or negative effect on the expression of the phenotype - Phenotypic Consequences of natural selection: - Stabilizing Selection: - Intermediate forms are favored compared to the extremes - Directional Selection: - Influenced by different and changing environmental factors - Disruptive Selection: - Forms at both ends of the range of variation are favored. - Intermediate forms are selected against. 1.5 Inspiration for understanding natural selection: - Went to the Galapagos Islands near the equator - Voyage of Beagle lasted 5 years - Darwin collected specimens of different finches Galapagos Finches: 14 Geospiza Species - One ancestral species had been taken and modified towards different ends. - Favorable variations would be preserved, and unfavorable ones would be destroyed. - They differed in the types of food they ate based on the type of beak that allowed it. - “Needed the right tool for the right job” which is why their beak was different from each other. - New land, a whole bunch of finches of a variety spreading out on the islands which cause them to develop different traits. - One species of finch arrived on the Galapagos Islands and then diversified because the DNA of those on the islands was much closer compared to that of the mainland - Come from a single common ancestor - Based on the environmental situation of a drought, the offspring had to develop bigger beaks to survive because seeds got harder and the abundance decreased. Processes that Drive Evolution: - Natural Selection, Coevolution, Sexual Selection, Genetic Drift Coevolution: Evolutionary arms race between species - Occurs when the anti-predator adaptations of a prey species cause reciprocal adaptations by the predator that counter or diminish the effects of the prey’s adaptations. Thus causing the prey to develop further adaptations and so on. Ghost of Predation Past: - Many adaptations of current species probably arose as coevolutionary adaptations to these large predators and herbivores. - Modern evolutionary biology cannot necessarily be understood in terms of current conditions and selective forces. Sexual Selection: - Differ between sex - Females within a species develop a preference for males with these exaggerated traits, leading to males with more pronounced features having a higher chance of mating and passing on those genes, even if the trait comes with survival costs - Essentially the reproductive benefit outweighs the survival cost in the eyes of natural selection - Males need to compete to reproduce while females choose who to mate with. - The female population puts a lot of energy into raising offspring. Genetic Drift: - Random changes in allele frequencies are brought about by chance alone. - Founder Effect: The genetics of the population reflect those of the initial members. When a small group of individuals establish a population, there will be a decrease in genetic diversity. - Bottlenecks occur when few members of the species survive. - After bottlenecks, genetic drift can significantly affect the population lowering its genetic diversity and decreasing its ability to survive. Carl Linnaeus: - Father of modern taxonomy - Created a uniform system for naming organisms (binomial nomenclature) - Kingdom, Phylum, Class, Order, Family, Genus, Species (King Phillip Came Over For Good Spaghetti) - Ring Speciation: - a situation in which two populations which do not interbreed are living in the same region and connected by a geographic ring of populations that can interbreed - Species: - 70% genomic identity - 95% transcriptomic identity - A high degree of phenotypic similarity - Speciation: - Allopatric: Geographical Barrier - Some type of barrier exists that prevents/reduces gene flow. Different mutations and different selection pressures cause divergence over time - Parapatric: Partial spatial isolation (Hybrid) - a process where a species evolves into two distinct groups while still exchanging genes - Sympatric: Genetic polymorphism (Repro.ductive isolation) - The divergence of a single breeding population of one species into two reproductive isolated populations without any barriers to gene flow. - Early Evolution on Planet Earth: - The First atmosphere: - Giant metal, ice, and rock collided to create Earth after the immense heat and pressure vaporized and created magma 4.5 billion years ago. - This caused water vapor and other gases to be released creating the first atmosphere that housed the greenhouse gases to insulate, heat, and melt the planet's surface. - The Oceans and the Moon : - The steam in the atmosphere created oceans with chemical-rich water - Something the size of Mars collided with Earth and shot out debris to create the moon - Hadeon Eon: - Molten rock or magma blessed - Little oxygen in atmosphere - Archeon Eon: - Oceans, lands rivers and beaches - Hydrothermal venting in ocean might have led to first life - Microbes began to affect atmosphere - Stromatolites made by microbes at 3.5 billion years - Life forms evolved to - Oxygen: - Oxygen became abundant and allowed forms of life to either thrive or perish - Formed the ozone layer to prevent life on Earth from getting harmed from ultraviolet light from sun. - Snowball Earth: - Timeline to the oxygen revolution: Protocells to Bacteria: - Hadean Eon led to the possibility of protocells ~4 BYA - Prokaryotic (most likely bacterial domain) ~ 3.8 BYA - Conditions were anaerobic on Earth Archaea: - Arised slightly after bacteria ~ 3.7 BYA - Extremely small archaea isolated from acid mine drainage in California may be descendants of the earliest archaea Anaerobic Bacteria Photosynthesis: - Beginning of anaerobic bacterial photosynthesis ~ 3.2 BYA - Aquifex is an example of a living fossil. Has cyclic photosynthesis and is an extremophile growing at 95 C Ancient Photosynthetic Bacteria (Aerobic): - Stromatolite fossil - Constructed by cyanobacteria around ~ 3.5-3 BYA - North Pole, Australia - AKA “Blue-Green Algae” Eukaryotes: - Beginning of more complex life ~ 2.7 BYA - A cell or organism with a defined nucleus Domains of Life: - Bacteria → Prokaryotes - Archaea → Prokaryotes - Euykarya Key Features of Prokaryotic Cells: - No nucleus - No membrane-bound organelles - DNA in nucleoid - Pili allows them to stick Key Features of Eukaryotic Cells: - Have a nucleus that stores genetic information - Mitochondria have their own set of DNA separate from that inside the nucleus - Animal Cells: - Don’t have a cell wall or chloroplast - Plant Cells: - Have chloroplast that enables photosynthesis and on top of a cell membrane, they also have a cell wall. - Chloroplast has separate DNA Key Features of both Prokaryotic and Eukaryotic Cells: - Cell membrane, cytoplasm, genetic material, ribosomes Origin of mitochondria and chloroplasts: - The origin of eukaryote cells includes the idea that organelles start as a symbiotic relationship between cells of varying types that ultimately results in engulfing one of the organisms into the other Scientific Theory: - A scientific event supported by scientific evidence. - Must be testable and tested over and over again Endosymbiotic Theory: - Eukaryote cells evolved from prokaryote cells - Variety in prokaryotes - Some could produce energy through photosynthesis - Some large prokaryotes consumed small prokaryotes and the small bacteria that survived after digestion lived within the larger prokaryotes as symbionts. - Ancient eukaryotes evolved into mitochondria and chloroplast but mitochondria came first because all eukaryotes have mitochondria and then later on some adapted to having chloroplast. - They divide in the same way bacteria divide. Universal Features of Cells: - Enclosed by a membrane - Store hereditary information in DNA - Replicate DNA using the same basic mechanism - Use RNA for transcription of DNA - Translate RNA into protein through RNA and ribosomes - Use proteins as a catalyst - Use ATP for free energy Cells are complex: - Most Archaea and Bacteria have 1-4k genes and a single chromosome - Eukaryotes have more genes, multiple chromosomes, and a variety of organelles Photosynthesis and Oxygen: - No oxygen in the early stages because there was no source. - Oxygen is highly reactive - The development of oxygenic or non-cyclic photosynthesis created oxygen and is the reason they are present in the atmosphere - Detect oxygen by the presence of iron and sulfur-oxidized compounds in fossil deposits Banded Iron Formations: - O2 levels increased - Aerobic respiration became the dominant form of metabolism among Bacteria Plants capture energy from sunlight with water and carbon dioxide to create sugar. Oxygen is released as by product Solar energy + 6 CO2 + 6 H2O gives you one molecule of glucose and 6 oxygen molecules Light reactions and Calvin cycle reactions - Light reactions happen in thylakoids by taking 2 wavelengths of light and creating ATP and NADPH - Calvin Cycle reactions - occur within the stroma - Uses ATP and NADPT to turn carbon dioxide into carbohydrates - The NADP+ and ADP also produced by Calvin cycle reactions are recycled for the next set of light reactions. Great Oxygen Crisis: - Earth’s orbit around the Sun is unstable which causes it to swing further out into space and start the cooling effect 2.4 billion years ago. The production of oxygen by cyanobacteria made the cooling process worse. - Oxygen caused the destruction of greenhouse effect that kept planet warm - Reflection of sunlight off the ice further cooled the planet - Precambrain from Hadean to end of Proterozoic: From ediacaran to cambrian: - Most of the species and life forms of the Ediacaran fauna had gone extinct by 540 MYA - The end of Ediacaran marked the beginning of the Cambrian, a period of unprecedented proliferation of species and phyla. Cambrian Explosion: - Rapid evolution and diversification of animal life on Earth around 542 million years ago. - After 45 million years of slow evolution, the weird creatures of the Ediacaran period died out when the Cambrian explosion started. - Theories of the event: - Oxygen availability: - The idea that oxygen levels increased which led to larger animals being able to survive and proliferate since oxygen was limited before - Mineral availability: - Increased availability of minerals in the oceans after glacial erosion which constructed shells and other hard parts for organisms - Bilateral symmetry: - Concentrates nerves and sense organs at an animal’s front - Ecological feedback: - The evolution of vision and other sensory systems due to the interaction between predators and prey. - Creating a runaway situation that would lead to rapid evolution - Role of Vision: - The ability to sense light and position prey with precision allowed predators to catch prey more effectively which then allowed prey to develop defenses such as hard areas of their bodies. - The Burgess Shale: - New species that resulted from the Cambrian explosions are shown in fossils Kepler Space Telescope: Monitors light brightness from a start to find certain dips in the light curve that a passing planet might cause. Ex: Kepler-22: First exoplanet discovered by Kepler to orbit in a star’s habitable zone that might contain liquid water. Goldilocks Zone: The habitable zone around a star where conditions are just right for liquid water to exist on the planet's surface. Life Requirements: - Growth: Ability to increase the size of parts not just accumulate matter - Response: Ability to react to environmental stimuli - Heredity: Ability to evolve traits over time - Homeostasis: Ability to regulate the internal state - Metabolism: Ability to convert/use energy to perform function - Reproduce: Ability to produce new organisms from the parent - Order: Generally characterized by ordered structures Are viruses alive? - No, because they don’t have a metabolism - They can freeze at low temperatures and when they return to normal temperatures, they survive - Viruses are parasites and require a host to survive - They hijack the host’s proteins and energy to replicate and make copies of themselves. - Protein and RNA are all you need to make a virus - Viruses can evolve Viruses-Types & Shapes: - Can have DNA or RNA as genetic material - It comes in all different sizes and shapes Simplest Known Bacteria: - Carsonella Ruddii - 182 genes (159,662 base pairs) - Obligate endosymbionts with aphids

Unit 1: Evolution Study Guide PDF

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