Fossils

Front

Method used to date 23,000-year-old starch grains on a seed-grinding stone in Israel.

Back

radioactive carbon-14 dating

Front

An index fossil may be used for identifying

Back

sedimentary rocks of the same age in different locations

Front

Potassium-40 has a half-life of 1.25 billion years. In igneous rocks closely associated with a fossil layer, the ratio of potassium-40 to argon-40 is approximately 1:1. What is the age of the fossils?

Back

1.25 billion years.

Front

Which of these organisms is the oldest?

Coral

,

Crinoid

,

Ammonite

,

Trilobite

Back

Trilobite

Front

Which of these organisms from the diagram would make the most suitable index fossil?

Gastropod

,

Crinoid

,

Ammonite

,

Trilobite

Back

Ammonite

Front

The half-life of Cobalt-60 is 5.27 years. What percentage of the initial Co-60 will remain after two half-lives?

Back

25%

Front

Atoms of the same element that have different numbers of neutrons are called

Back

isotopes

Front

What term describes the time required for one half the atoms of a given amount of a radioactive substance to decay?

Back

Half-life

Front

Which of the following conditions are NOT required for fossilisation to occur? Options: Presence of decay organisms, Alkaline soil, Hard body parts (bones, teeth, shells), low oxygen conditions

Back

Presence of decay organisms

Front

What is the term for the relative dating technique concerned with the study of rock layers (strata) and layering?

Back

Stratigraphy