Exam 1 Lecture 1/2 Flashcards
(19 cards)
Fossils
-Records of a living thing
-Can tell us about environment and age
How sedimentary rock form
- Erosion happens
- Sediments carried
- Sediments settle in layers, solids into rocks = Sedimentary rocks
Erosion
Rocks break down into smaller pieces due to water and wind
How fossils form
Organism is buried by sediments
Most likely to fossilize
-Shelled animal (hard structures)
-Widespread (found more)
-Aquatic organisms
-Larger organisms (found more)
How to find fossils
-Digging into layers
-Mining
-Searching
-If on top of layers, found more recently
Fossils
-Records of living things
-Can tell us about environment and age
Radiometric dating
Used to date rocks or carbon
Half life
How ever much time it takes to lose 50% of thing
Fossilization bias
-Larger and more widespread organisms are found more often, leaving organisms in other areas unknown
-Softer body animals decay
-Animals in dry environments decay
How radiometric decay works
-Some fossils are radioactive
-These slowly decay into stable elements
-measure how much of the original is left and how much of new is created
-Using the half life, age is calculated
Radiometric decay example
-You can find out age of rocks around bone to estimate how old the bone is
Oparin-Haldane model step 1
Simple molecules to building blocks for complex polymers
Oparin-Haldane model step 2
Assemble polymers that can store info and catalyze reactions
Oparin-Haldane model step 3
Add membranes and energy source to make living organism
what is the Oparin-Haldane model
-Explains how life may have originated on earth
-Simple molecules gradually formed complex organic molecules
Evidence for Oparin-Haldance model
-Spontaneous formation
-Extra-terrestrial sources
Miller-Urey (1953)
-Vaporized water and let it pass through CH4, NH3, H2
-New H20 was brown
-Found amino acids
-Spontaneous formation
Spontaneous formation
-With right environment, amino acids and nucleotides form
