EOCT Review Answers Introduction EOCT Review guide page 1 1 • Biology is the study of life. 2 • • • • • • • • 1.) Need food. 2.) Reproduce 3.) Use energy 4.) Grow and develop 5.) Maintain Homeostasis 6.) Have DNA 7.) Adapt & Respond to stimuli 8.) Made of at least one cell. 3 • Homeostasis is an organism’s ability to regulate its internal environment. • Example: – When your temperature goes up, you sweat to cool yourself off. When you get cold, you shiver to warm up. • Importance: – Without being able to respond to changes in its internal environment, an organism would die. 4 • • • • • • 1.) Observation 2.) Hypothesis 3.) Prediction 4.) Experiment 5.) Data Collection 6.) Conclusion 5 • Independent variable: – is the variable being tested. – is the variable the experimenter makes different between the different groups. – is also called the manipulated variable. • Dependent Variable: – Is what changes because of the independent variable. – Is what is measured in the experiment. – Is called the responding variable. 6 • Qualitative data: – Involves characteristics/descriptions. – Ex: The plant’s leaves changed from green to yellow-brown. • Quantitative data: – Involves numbers/calculations. – Example: 25% of the plant’s leaves changed colors on the first day. 7 Chart Summarizes data in rows/columns Bar Graph Compares different data (magnitude) Line Graph Shows how data changes over time Circle Graph Shows how parts relate to the whole Flowchart Shows order of steps 8 • Know these branches of biology. Domain I Cells EOCT Review Guide pages 2-4 1 • A.) All living things are made of cells. • B.) Cells are the basic unit of structure and function in living organisms. • C.) All cells come from existing cells. 2 • Eukaryotes: – Have a nucleus – Have membrane-bound organelles • E.R., Golgi, vesicles, lysosomes, mitochondria – Some can be multicellular. • Prokaryotes: – No nucleus – No membrane-bound organelles • No E.R., No Golgi, No vesicles, No lysosomes, No mitochondria – Only unicellular 3 • The cell membrane (plasma membrane) is made up of phospholipids and proteins. 3 continued… 4 • Selectively Permiable: – Only certain substances can cross the membrane and come into/go out of the cell. – Substances that can cross freely: • • • • Water Amino acids Gases Sugars 5 • A.) Receptor • A protein that serves as a receiving point for cellular messages or signals. • B.) Marker • A protein that indicates the cell’s identity • Important in immunity • C.) Channel • A protein that serves as a doorway into the cell for large or electrically charged molecules. 6 Organelle Nucleus Function Store & protect DNA; “control center of the cell.” Pro/Eu/Both Animal/Plant/Both EU Both Controls what can go into/out of the nucleus EU Both Ribosomes Make proteins Both Both Mitochondria Make ATP EU Both Chloroplast Make sugar EU Plants Nuclear Envelope 6 continued E.R. Golgi Transport proteins from EU ribosome to golgi; make lipids Modify, package and ship proteins. Both EU Both Cell Membrane Controls what can go into/out of the cell Both Both Cell Wall Provides shape and external support to the cell. Both Plants Cytoplasm Contains building Both blocks for molecules Both 7 • Active transport requires ATP energy. • Passive does not require any energy. 8 • Diffusion – Movement of particles from high concentration to low. • Facilitated Diffusion – Diffusion of large molecules using channel proteins. • Osmosis – Movement of water from high concentration to low. • Endocytosis – Active transport that brings large molecules into the cell by engulfing the molecule. • Exocytosis – Active transport that sends molecules out of the cell. 9 • Picture 1 = Isotonic • Picture 2 = Hypotonic • Picture 3 = Hypertonic 10 • Chemical reaction = results in new chemicals being formed. • Physical reaction = changes the shape/structure of the molecules, but no new molecules are formed. 11 • Reactants = on the left • Products = on the right • Example: CO2 + H20 + light Sugar + O2 REACTANTS PRODUCTS 12 • Endothermic = – absorbs energy. – Photosynthesis is endothermic. • Exothermic = – Releases energy – Cell respiration is exothermic 13 • Enzymes: – Proteins that catalyze (speed up) chemical reactions. 14 • Substrate: – Molecule being changed by the enzyme-catalyzed reaction. 15 • Active site 16 • On board… 17 • A.) pH changes • Can change the shape of the enzyme, resulting in it not functioning. • B.) Temperature changes • Cold: molecules move slower, so are less likely to encounter enzymes. • Hot: changes shape of enzyme • General rule: as the environment gets warmer, enzymes work faster. HOWEVER, too hot = denatured enzyme. • “Denature”: – Means: “Change the shape of an enzyme.” 18 • Water has a slightly positive and slightly negative end. – due to the unequal pull on the electrons by the molecules. – Oxygen is “stronger” than hydrogen, so it can pull on the electron in the bond more. – The electron is closer to the oxygen, so oxygen becomes negative and hydrogen becomes positive. 19 • Your cells and the cells of all other organisms are made mostly of water. • Water gives cells structure and transports substances within the organism. • All cell processes take place in a watery environment. 20 • Homogeneous solution: – a mixture where the components that make up the mixture are uniformly distributed throughout the mixture. – Ex: blood, air, sugar water • Heterogeneous solution: – a mixture where the components of the mixture are not uniform or have localized regions with different properties. – Ex: oil and water, soup, muddy water 21 • C.) 0-6.9 • D.) 7.1-14 22 Macromolecule Function Monomer Example Carbohydrate Provide energy Monosaccharide Glucose, sucrose, starch Lipid Store energy, provide insulation, make cell membranes No true monomer, but made of glycerol and 3 fatty acids. Phospholipid, waxes, oils, fats Protein Markers, channels, receptors, build bones and muscles, act as enzymes Amino acids Enzymes Nucleotide DNA & RNA Nucleic Acid Store and transmit heredity; contain information for making proteins Domain II Organisms EOCT Review pages 5-7 1 • ATP is a nucleotide. • It is used as a source of energy in the cell. 2 • ATP releases energy as bonds are broken. • A–P–P–P This bond is broken • A–P–P + P This is ADP…which is a lower energy molecule than ATP. 3 • Cell use energy for: • • • • • • Respiration Photosynthesis (in plants) Digestion (in animals) Reproduction (meiosis) Active transport Growth and repair (mitosis) 4 Process Photosynthesis Cell Respiration Organelle where it occurs Chloroplast Cytoplasm and Mitochondria CO2 + H20 + LIGHT What is needed? CO2, H20, LIGHT Sugar (glucose) and Oxygen What is produced? Sugar (glucose) and Oxygen CO2, H20, 36 ATP Sugar (glucose) + Oxygen 5 • PLANTAE!!!!! • And…Some bacteria and some protists. 6 • Sugar (glucose) + Oxygen CO2 + H20 + 36 ATP 7 • All eukaryotic kingdoms perform respiration: – Plantae – Protista – Animalia – Fungi 8 • Autotroph; Producer 9 • Heterotroph; Consumer 10 • Fermentation is a process that occurs when there is not enough oxygen to run steps 2 (Krebs cycle)and 3 (Electron transport chain) of cell respiration. • It happens in the cytoplasm. 11 • The glucose is broken in half during step 1 of cell respiration (glycolysis) to form two pyruvate molecules. • The pyruvate is changed into lactic acid, which allows glycolysis to happen again. • You feel the lactic acid build up as a burning sensation in your muscles. 12 • Taxonomy is the scientific study of classifying organisms into groups based on characteristics. 13 • Homo sapiens • Homo = genus name • sapiens = species name. 14 • • • • • • • K P C O F G S 15 • A taxon (pl. taxa) is a level of classification. – K, P, C, O, F, G, and S are taxa. 16 • • • • • Similar DNA sequences (biochemistry) Physical similarities Geographic distribution Chromosome comparisons Breeding behavior 17 • It allows for an orderly study and makes comparisons between organisms possible. 18 • Evolutionary relationships are another way to determine how closely two species are related. 19 • Old bacterial kingdom = Monera • Scientists realized that some bacteria were as different from other bacteria as plants are from animals. – So, they needed to be in different kingdoms. • Thus, the birth of kingdoms Archaebacteria and Eubacteria 20 • A tool used to determine the identity of an organism based on physical characteristics. 21 • A = house fly • B = Grasshopper • C = Ladybug • D = dragonfly 22 • A cladogram is a diagram showing evolutionary relationships and history between organisms. 23 • A.) Mosses • Technically it is the green algae ancestor, but of the clades listed, Mosses are the oldest. • B.) Ferns, Cone-bearing plants and Flowering plants • C.) Cone-bearing plants and flowering plants • D.) Flowering plants 19…don’t know why it is numbered 19….accept it and move on. Characteristic Archaea Bacteria Protista Fungi Plantae Animalia Cell Type PRO PRO EU EU EU EU # of cells 1 1 1+ Some 1+, most multi Multi multi Nucleus NO NO YES YES YES YES FOOD? Some auto/ some hetero Some auto/ some hetero Some auto/ Hetero some hetero Auto Hetero Cell wall? YES YES Some YES YES NO Photosyn? NO A few A few NO YES NO Ex: Thermophiles -E. Coli Methanogens -Staph -Strep Plants Animals Euglena -Mold Amoeba - Yeast Paramecium 24 • Binary fission is an asexual method of reproduction that occurs in bacteria. It is very similar to mitosis: – 1.) The bacterial DNA is copied. – 2.) The copied DNA moves to opposite sides of the cell. – 3.) The cell splits in half forming two identical cells. 25 • Decomposers return nutrients into the soil (and atmosphere in the case of carbon (CO2) allowing the cycle to continue. 26 • Viruses are considered non-living because: – 1.) They cannot reproduce on their own. (They need a host). – 2.) They are not made of cells. – They are essentially a bag made of protein with DNA or RNA in the bag. 27 This is a BACTERIOPHAGE. (A virus that infects bacteria) Pay special attention to the CAPSID and the DNA. These are the two most important parts for you to know!!! 28 • In the lytic cycle, the virus: – 1.) completely takes over the cell – 2.) uses the cell’s organelles to make new viruses – 3.) causes the cell to explode, releasing the new viruses. These are very fastacting viruses. • In the lysogenic cycle, the virus: – 1.) hides its DNA in the host cell DNA. – 2.) reproduces only as fast as the host cell goes through mitosis. – 3.) may lie hidden for years before the person shows any symptoms. These tend to be slow-acting viruses. 29 • A very basic explanation: – 1.) The virus enters the host cell. – 2.) The virus is copied within the cell. • Either by – taking over the cell (lytic cycle) or – by being copied as the host cell divides (lysogenic cycle) – 3.) The new viruses leave the cell to infect other cells. Domain III EOCT review guide pages 8-12 1 • Interphase & Cell Division 2 • G1 = cell grows and carries out its normal job. • S phase = DNA is copied (replicated/duplicated) • G2 = Cell prepares for division 3 • During mitosis, the nuclear membrane breaks down and the copied chromosomes are separated to either side of the cell. (this is mitosis) • Then , the cell divides. (This is cytokinesis) 4 • The cytoplasm of the cell divides, cutting the cell in half. • In animals, the cell pinches in half. • In plants, the cell builds a new cell wall in the middle of the cell. The new cell wall is called a cell plate. 5 • • • • • • A = Early Prophase B = Telophase C = Metaphase D = Interphase E = Anaphase F = Late Prophase 6 Phase Description Prophase DNA condenses to form chromosomes. Nuclear envelope breaks down. Metaphase Copied chromosomes line up at the center (equator) of the cell. Anaphase Copied chromosomes (sister chromatids) split apart and begin moving to the poles of the cell. Telophase The exact opposite of prophase. DNA unwinds and the new nuclear envelopes reform. 7 • Mitosis is for growth and repair. • Meiosis is for production of gametes 8 • Haploid = a cell with half the normal number of chromosomes. These cells are usually gametes. • Diploid = a cell with a full set of chromosomes. These cells are usually somatic cells. 9 Asexual & Sexual Similarities •Both are types of reproduction •Both involve the production of new cells Differences •Asexual produced identical cells. •Sexual produces different cells. •Asexual is an advantage when the environment is stable. •Sexual is an advantage when the environment is changing. 10 • Mitosis is asexual because the daughter cells are identical to the parent cell. 11 • Meiosis is sexual because the daughter cells are different from the parent cells. 12 Body cell or sex cells? # of divisions? # of stages (total)? # of cells produced? # of chromosome s in cells produced? Mitosis Body cells 1 4 (PMAT) 2 Same number (cells are diploid) Meiosis Sex cells 2 8 (PMAT, PMAT) 4 Half (cells are haploid) 13 • A gamete = a sex cell (sperm or egg) • Gametes are haploid. • Sperm are produced via spermatogenesis. • Eggs are produced via oogenesis. 14 • Crossing over is the exchange of DNA between homologous chromosomes. • It occurs during Prophase 1 of meiosis. • You have a picture of crossing over on your study guide. 15 • DNA is in the nucleus in eukaryotes (in the cytoplasm in prokaryotes). • RNA can be in both the nucleus and the cytoplasm. 16 • 3 parts of a nucleotide = Phosphate, sugar and a nitrogen base. • The drawing is already labeled. 17 • DNA nitrogen bases: • • • • Adenine Thymine Guanine Cytosine 18 • Chargaff’s rule: • A with T and… • C with G 19 • Given: ATGCCGT • Asked: TACGGCA 20 • DNA is a double helix (“twisted ladder”.) 21 • Watson and Crick 22 • During DNA replication, a copy of the DNA is made. – Each new copy is made of one original strand and one new strand. • This is called semi-conservative replication. 22 continued… 23 • 1.) The DNA separates (due to enzymes) • 2.) The two strands are copied. 24 • SKIP this question… 25 • Adenine -- Uracil • Guanine -- Cytosine 26 • ATGGTCA – “DNA strand - given” • UACCAGU – “complementary mRNA strand” 27 • Messenger RNA = C • Transfer RNA = A • Ribosomal RNA = B 28 • During transcription, mRNA is made from a section of DNA. • It happens in the nucleus – WHY??? 29 • During translation, a protein is made by the ribosome. – The ribosome reads the mRNA message and makes the protein. • This happens at a ribosome (either in the cytoplasm or attached to the E.R.). 30 • codon 31 • 20 different amino acids are possible 32 • Proteins: – Build muscles and bones – Provide ways for cells to communicate with other cells. – Serve as enzymes – Function as antibodies – Serve as channels for substances to enter the cell • Facilitated diffusion (a type of passive transport) – Serve as pumps to move things in and out of the cell (Active transport) 33 • Missense = one codon is changed, resulting in a different amino acid being produced. (GUA GGA) • Nonsense = a change in a codon causes a stop codon to be produced. (CGA UGA) • Insertion = an extra base is added to the DNA sequence. • Deletion = a base is deleted from the DNA sequence. • Duplication = an copy of a sequence of DNA is added to the same DNA strand. 34 • Point mutations only affect one codon. • Frameshift mutation affect all codons in the DNA strand after the mutation. • Remember: THE FAT CAT WAS MAD. 35 • Mendel was the first person to scientifically study inheritance. • He is considered the “Father of Genetics”. 36 • He studied pea plants. • Why: – 1.) They reproduce sexually by self-pollination. – This allowed Mendel to control what traits he was testing for. – 2.) They were easy to grow, easy to maintain and were easy to obtain. 37 • Homozygous 38 • Heterozygous 39 • Dominant 40 • Recessive 41 • The genetic make up of an organism – You cannot “see” this, but you can infer it. 42 • The physical trait coded for by the alleles. – You can see this. 43 • Your Parents = P generation • You = F1 generation • Your kids = F2 generation 44 • B= black; b= brown • a.) BB = homozygous black • b.) bb = homozygous brown • c.) Bb = heterozygous black 45 • Tt x Tt T t T TT Tt t Tt tt • Phenotypic ratio = 3 tall: 1 short • Genotypic ratio = 1 TT: 2 Tt: 1 tt 46 • Law of Segregation: – Alleles separate during gamete formation. • Law of Independent Assortment: – Essentially…just because you are dominant for one trait does not mean you will be dominant for all other traits, too. 47 • Female = XX • Male = XY 48 • Incomplete dominance is an inheritance pattern where two dominant phenotypes blend together to produce a new phenotype. • Example: Red flowers + Yellow flowers = Orange flowers Orange is a NEW phenotype (it’s not red and it’s not yellow…it’s orange.) 49 • Codominance is where two dominant phenotypes combine to produce a striped or spotted heterozygous phenotype. • Examples: Chic-fil-A cows. 50 • Sex linked traits are traits carried on the X chromosome. • Examples: – Hemophilia; – green vs blue eye color; – some muscular dystrophies; – colorblindness 51 • A polygenic trait is a trait controlled by more than one gene. – It allows for a lot of variance in the phenotype. • Example: Human skin color; Human height 52 • A mutation is any change in an organism’s DNA. • 4 Causes: – UV radiation – X-rays – Viruses – Certain chemicals 53 • A karyotype is a picture of a person’s chromosomes. • It is used by doctors before a baby is born to determine if the baby will have any genetic disorders. 54 • Skip this question… 55 • Nondisjunction is a problem in meiosis whereby the daughter cells do not get the right number of chromosomes. • Cause: failure of chromosomes to separate during anaphase. 56 • A.) Extra chromosome 21 = Down Syndrome • B.) missing X chromosome = Turner’s syndrome (female, 45X0) Domain IV Ecology EOCT Review pages 13-17 1 • Ecology: – The study of the interactions among organisms and their environment. 2 • All areas on earth where life exists. – Entire Earth + all Biomes. 3 • Abiotic = non-living • Biotic = living 4 • Biotic: – animals, plants, bacteria, fungi • Abiotic: – rocks, soil, climate, precipitation, weather 5 • Species population community Ecosystem Biome biosphere 6 • Population = all members of same species in an area. • Community = many different populations in an area. • Ecosystem = all communities and the abiotic factors that affect them. • Biome = area of Earth with similar ecosystems and similar dominant species. 7 • Habitat = where an organism lives. • Niche = the organism’s role in the habitat. 8 • Competition = two organisms trying to get same resources or mates . • Predation = one organism hunting, killing and eating another organism (the prey) 9 • Mutualism = both species benefit • Commensalism = one species benefits and the other one is neither helped nor harmed. • Parasitism = one species benefits by harming (but not intentionally killing) the other. 10 Organism Energy Source Example Producer Sun Plants; some bacteria Herbivore Producers Cow, sheep, rabbit, shrimp Omnivore Producers and consumers Bears; humans Carnivore Consumers Dead organisms Wolves, Lions, sharks Decomposer Fungi and bacteria 11 • Answers will vary… 12 • The sun and decomposers 13 • A food web is more complex and is made of many food chains. • It shows all of the different interactions in an ecosystem. 14 • The sun 15 • Level 1 = producer • Level 2 = primary consumers • Level 3 = secondary consumers • Level 4 = tertiary consumer • Level 5 = quaternary consumer 16 • Only 10% of the energy at any trophic level can passed to another organism. • The other 90% is lost as heat. 17 • Results will vary… 18a • Carbon is taken in by plants to produce glucose in a process called photosynthesis. The glucose molecule is then broken down for energy by heterotrophs during a process called cellular Respiration, in which CO₂ is released to be taken in by plants again. Carbon is also put into the atmosphere by the burning of fossil fuels. Decomposers release carbon back into the ecosystem by breaking down dead organisms whose cells contain carbon. 18b - Nitrogen • Nitrogen gas makes up about 68% of our atmosphere, but it is not useable in this form. Bacteria perform a process called Nitrogen fixation which is a process that “fixs” nitorgen into a useable form for organisms. This entire process requires BACTERIA. 18c - Phosphorus • Phosphorus is put into the soil and used by plants by the eroding of rock materials. The process is the SLOWEST of all the nutrient cycles, because it takes so long for rocks to be eroded by water. 18d - Water Cycle • • • • • • • Evaporation Transpiration Condensation Precipitation Run Off Seepage (ground water) Starts all over 19 • Nutrients need to be transferred among members of a food web. • In order for the nutrients to be returned to the soil for producers to use again, the decomposers must recycle the nutrients. 20. Ecological Succession • After a disaster such as lava flow, tornado, flooding, fire or receding of a glacier, the ecosystem must be rebuilt. The process of re-growth happens in a logical order called succession. 21. • Both end in a mature ecosystem called a climax community. The main difference is how they begin. Primary starts on bare land, often after a volcanic eruption or receding of a glacier. There is no soil in Primary succession and thus a pioneer species must come first. Often this pioneer species is lichens that can grow on rock. Secondary succession occurs when soil is left such as after a farm has been abandoned or a tornado. 22. • • • • Tornado Fire Flooding Clear cutting 23. • Pioneer species are the first organisms to inhabit an area. They prepare the environment for other species to grow. • Lichen = primary successions • Grass = secondary succession 24. • The final most mature ecosystem that results at the end of either primary or secondary succession. 25. • Factors that change as the result of the number of organisms inhabiting an area. • They only affect large populations! 26. • Competition (for food, mating, territory, or shelter) • Disease • Predation • Parasitism 27. • Factors that are not affected by the number of organisms or individuals in an area, but still impact the carrying capacity of that area. • Affects all populations equally! 28. • Human Impact • Weather conditions • Disasters 29 • See Board 30. • Exponential growth is the sudden and rapid • Logistic growth slows down as resources run out and the population reaches carrying capacity. 31 • Carrying capacity is the number of individuals that a certain area can support due to limited resources. 32 33 THREAT CAUSE POSSIBLE RESULT Greenhouse effect Gases in the atmosphere trapping heat. The gases are methane, CO2 and H20 Increased temperature on Earth; melting of glaciers; increased ocean levels; death of organisms Acid Rain Pollution from burning fossil fuels. Death of producers in land and aquatic environments Ozone Depletion CFCs from aerosols Increased UV rays reaching the Earth’s surface. Air Pollution Burning Illnesses Water Pollution Chemicals and human waste Death of organisms; poisoning of drinking water Soil depletion Erosion Stripping land of nutrients Habitat destruction Human activities Death of organisms 34 Non-renewable Resource •A resource that can only be used once. Renewable Resource •A resource that can be used over and over again and not be depleted. •It cannot be remade at a rate that is useful for human life. •The earth might make more, but it takes millions of years. Fossil fuels Wind Water Wood 35 • A.) Phototropism = plants respond to light • B.) Thigmotropism = plants respond to touch. • C.) Gravitropism (aka: Geotropism) = plants respond to gravity. • D.) Hydrotropism = plants roots search for water underground. 36 • The only one you need to know is ethylene: – It is a natural plant hormone that causes fruit to ripen. – Grocery stores spray this on fruits and vegetables to make them ripen faster. 37 • Only two you need to know: – Xylem • Tissue that moves water within a plant – Phloem • Tissue that moves sugars within a plant 38 • A.) tearing meat • B.) to hear threats from all around. • C.) swimming • D.) camouflage • E.) breaking down the cell walls in the plant matter they eat. • F.) to see predators from far off. 39 • Refer to the BIOME note sheet you were given in class. – It was a two sided sheet with all biomes listed and information about each. Domain V Evolution EOCT Review pages 18-19 1 • 4.6 Billion years ago 2 • The remains of ancient life. 3 • Skip this question 4 • Animals die; layers of silt deposit over them; the pressure from the silt helps to form fossils over time. 5 • Evolution is the change in organisms over time. 6 • Population genetics: The study of the genetic sequences in a population. • Adaptations: Any characteristic that aids an organism in survival and/or reproduction. • Speciation: the evolution of new species • Fitness – the likelihood that an organism will survive and reproduce in its environment. • Phylogeny: The evolutionary history of a species. 7 • A.) Lyell gave Darwin the evidence that natural processes that occurred in the past could still be occurring today. • B.) Malthus made observations about how limited resources lead to struggles for survival. Darwin applied this to all organisms. • C.) Wallace and Darwin were both studying evolution at the same time. 8 • Lamarck believed that organisms could acquire characteristics during their lifetimes and pass those characteristics on to their offspring. • He was wrong. 9 • He was wrong. • While organisms can aquire characteristics during their lifetimes through use and disuse, they cannot pass these characteristics on to their offspring. 10 • Darwin stated that organisms born with characteristics that make them more likely to survive and reproduce (i.e., more fit) will survive and reproduce more than those who lack the characteristic. • Future generations will look like the survivors. 11 • He went all around the world. • He saw varieties of different organisms in similar ecosystems. • He collected specimen for analysis and comparision. 12 • He noticed: – 1.) Organisms produce more offspring than can possibly survive. – 2.) Members of populations have natural differences in phenotypes. – 3.) He hypothesized that organisms with adaptations that make them more likely to survive and reproduce in an environment will survive and pass those traits on to their offspring. – 4.) He concluded that the future generations will be made of the offspring of the most fit organisms, and therefore exhibit those traits. 13.) • Geographic isolation. 14 • A.) this is where related organisms develop different traits due to living in different ecosystems. • Ex: Horses and Tapirs; elephants and manatees. • B.) this is where two unrelated organisms develop similar adaptations due to living in a similar ecosystem. – Ex: sharks and dolphins look similar. • C.) This is when the evolution of one species drives the evolution of another species. – Example: lions and zebras. 15 • A.) This shows how ancient life looked and allows us to determine the age of organisms. • B.) This shows relatedness among organisms due to similar body structures. • C.) this shows how organisms have changed over time. • D.) This allows scientists to compare living organisms to determine relatedness. • E.) Organisms on the same continent tent to be more closely related to each other than to organisms on other continents. 16 • It is a measure of how able an organism is at surviving and reproducing in its environment. 17 • This allows them to blend in, hide and ambush prey. 18 • Click this link: • http://www.youtube.com/watch?v=6jBD8xfbf4Y 19. • 1.) Mutations • 2.) Gene shuffling • Principle of segregation • Crossing over 20 • Skip this question 21 • Gradualism is slow, steady change over time. • Punctuated equilibrium is long periods of stability with periodic episodes of speciation. • See next slide… 21 continued.