ch 19

Question 0

explain the process by which fossils are formed

Answer 0

sediment is transferred by water and the hard parts are replaced with minerals (layer- strata)

Question 1

compare the 5 different types of fossils

Answer 1

permineralized- minerals are carried by water and decompose around structure (bone to rock)

natural costs- flowing water removes original tissue

trace fossils- record of activity of organisms

preserved remains- found in ice or peat bog

amber preserved- preserved in tree resin

Question 2

what types of information can paleontologists determine from fossils?

Answer 2

structure
diet
predators
environment

Question 3

distinguish between relative and radioactive dating

Answer 3

relative- age is determined by placement of fossils, lower layers contain older examples, and index fossils are used to compare ages

radioactive- uses radioactive isotopes to age fossils, they decay into nonradioactive elements at a steady rate

Question 4

what is the half-life of C14?

Answer 4

5730 years

Question 5

what other isotopes can be used to date older fossils?

Answer 5

potassium 40
uranium 238
rubidium 87

Question 6

list the divisions of the geological time scale from largest to smallest

Answer 6

DK

Question 7

describe the nebula hypothesis

Answer 7

gas and dust were swirling. some collided to build up and melt together. elements then arranged according to density