Biology 12.1 The Fossil Record
Unlock all answers in this set
Unlock answersquestion
minerals carried by water are deposited around a hard structure ; may also replace the hard structure itself
answer
Permineralization
question
when flowing water removes all of the original bone or tissue, leaving just an impression in sediment ; minerals fill in the mold, recreating the original shape of the organism
answer
Natural casts
question
record the activity of an organism ; include nests, burrows, imprints of leaves, and footprints
answer
Trace fossils
question
organisms that become trapped in tree resin that hardens into amber after the tree gets buried underground
answer
Amber-preserved fossils
question
when an entire organism becomes encased in material such as ice or volcanic ash or immersed in bogs
answer
Preserved remains
question
estimates the time during which an organism lived by comparing the placement of fossils of that organism with the placement of fossils in other layers of rock
answer
Relative dating
question
technique that uses the natural decay rate of unstable isotopes found in materials in order to calculate the age of that material
answer
Radiometric dating (estimating actual age)
question
atoms of an element that have the same number of protons but a different number of neutrons
answer
isotope
question
amount of time it takes for half of the isotope in a sample to decay into a different element, or its product isotope
answer
half-life
