Biology
Order by
53 terms
Terms | Definitions |
|---|---|
 Define Genetic Engineering | Method of cutting DNA from one organism and inserting the DNA fragment into a host organism of the same or a different species |
| Recombinant DNA | DNA made by recomgining fragments of DNA from different sources |
| Transgenetic Organism | organisms that contain functional recombinant DNA from a different organism |
| Plasmid | a small ring of DNA found in a bacterial cell that is used as a biological vector. |
| Benefits of cloning | identical replica |
| Benefits of gene therapy | curing diseases with DNA |
| Benefits of DNA fingerprinting | used to catch criminals |
| What is the controversy over GMOs | When you mess with the DNA of the foods it changes its genes |
| trace fossil type | a trace fossil is any indirect evidence left by an animal, footprint |
| Casts | when minerals in rocks fill a space left by a decayed organism, replica |
| Molds | a mold forms when an organism is burried in sediment and then decays, leaving an empty space. |
| Petrified | with this fossil, minerals sometimes penetrate and replace the hard parts of an organism. Permineralized, void spaces in original organism infilled by minerals |
| Amber preserved | when an entire organism is quickly trapped in ice or tree sap that hardened into amber |
| How are fossils formed? | organisms are burried in mud, sand or clay and are compressed over time and hardened into a type of rock called sedimentary rock. |
| Relative dating | relative age and the order of appearance of the species that are preserved as fossils in the layers |
| Radiometric dating | uses radioactive isotopes in rocks to find the specific ages of rocks. calculates using half lifes |
| How do fossils tell us about what creatures roamed the earth millions of years ago? | By examining fossils scientists can learn about the creature, its environment, plants and what the creature ate. |
| What are the four major divisions of the geological time scale? | Precambrian Paleozoic Era Mesozoic Era Cenozoic Era |
| How old is earth and the oldest fossil? | Earth: 4.6 billion years; fossil: 3.4 billion years |
| Describe the theory of plate tectonics | 245 million years ago, the continents were joined as a land mass known as Pangaea. By 135 million years ago, Pangaea broke apart resulting into two large land masses. By 65 million years ago, the end of the Mesozoic, most of the continents had taken their modern shapes. |
| Spontaneous generation | the idea that nonliving material can produce life |
| Describe Redi and Pasteur's experiment | Redi used meat to convince scientists that maggots and did not arise from spontaneous generation. Pasteur disproved the spontaneous generation of micororganisms. His study used air but no microorganisms were allowed to contact the broth. |
| What was the purpose of Miller and Urey's experiment? | they supported the idea that the earth's ancient atmosphere contained the gases nitrogen, methane and amonia but not free oxygen. Energy from the sun, volcanoes and lightning caused chemical reactions among these gases which eventually combined to make amino acids. |
| What is the scientists' theory of how a cell evolves? | The early organisms were probably anaerobic, heterotrophic prokaryotes. Over time, chemosynthetic prokaryotes evolved and then photosynthetic prokaryotes that produced oxygen evolved. changing the atmosphere and triggering the evoloution of aerobic cells and eukaryotes. |
| Describe the endosymbiont theory | one bacteria began to eat another cell, one inside was able to survive. |
| Who is Charles Darwin? | Developed the modern theory of evolution |
| Artificial Selection | breeding organisms with specific traits in order to produce offspring with identical traits |
| Natural Selection | a mechanism for change in pouplations and occurs when organisms with favorable variations survive and pass their variations to the next generation. |
| Camoflauge | enables species to blend with their surroundings |
| Mimicry | a structural adaptation that enables one species to resemble another. |
| physiological | certain biochemistry |
| How are fossils used as evidence for evolution? | They provide a record of early life. |
| Homologous | structures can be similar in arrangement in function or in both. |
| Analogous | perform the same function but do not have a common evolutionary origin |
| Vestigal | A body structure in a present day organism that no loger serves its original purpose. |
| Embroylogy | it is the shared features in the young embroys that suggest evolution from a distant, common ancestor |
| Biochemistry | all organisms share DNA, ATP and many enzymes among their biochemical molecules. |
| Gene Pool | All of the alleles of the populations |
| Allelic frequency | the percentage of any specific allele in the gene pool |
| genetic equilirium | a population in which the frequency of alleles remains the same over generations |
| speciation | evolution of a new species |
| polyploidy | may result in immediate reproductive isolation when a polyploid mates with an individual of the normal species and the resulting zygotes may not develop normally because of the difference in chromosome numbers. |
| Adaptive radiation | when an ancestral species evolves into an array of species to fit a number of diverse habitats. |
| Explain 3 ways genetic equilibrium can change | Mutation, genetic drift and gene flow can change a populations genetic equilibrium |
| Stablizing selection | natural selection that favors average individuals in a population. the picture is where two curves mirror each other |
| directional selection | when national selection favors one of the extreme variations of a trait. the picture is like a wave |
| disruptive selection | individuals with either extreme of a traits variation are selected. the picture is a blue line with two humps and a red one with one hump. |
| Geographic isolation | when a physical barrier divides a population |
| reproductive isolation | when formerly interbreeding organisms can no longer mate and produce fertile offspring |
| gradualism equilibrium | the idea that species originate through a gradual change of adaptations. |
| punctuated equilibrium | the species occures relatively quickly in rapid burstswith ong periods of genetic equilibrium inbetween. |
| divergent evolution | the pattern of evolutionin which species that once were similar to an ancestral species diverge or become increasingly distinct. |
| convergent evolution | when distantly related organisms evolve similar traits |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.