Question

2 fill in the blank 2 points index fossils were left by species that lived over a relatively brief span of time, making them useful for the relative dating of rock layers. to determine the absolute age of fossils, scientists can use by applying the known of an isotope. 3 multiple answer 3 points fossils reveal the body structures of ancient ation can be concluded or inferred from studying fossils? select all that apply. the ecology of ancient environment evolutionary lineages from common ancestors. the colorations and markings of ancient organisms. sequential nature of ancient organisms. 4 multiple choice 1 point the diagram shows the bone structure of the front leg of a frog and an alligator. the general structure between the two animals is similar, but the lengths of the bones are different.

Explanation:

Question 2 (Fill in the Blank)

To determine the absolute age of fossils, scientists use radiometric dating by applying the known half - life of an isotope. Index fossils are used for relative dating (to find the relative age of rock layers), and radiometric dating is the method for absolute age determination as it relies on the decay of radioactive isotopes with a known half - life.

• The ecology of ancient environment: Fossils can tell us about the environment in which ancient organisms lived. For example, the presence of marine fossils in a certain area can indicate that the area was once under water.
• Evolutionary lineages from common ancestors: By studying the similarities and differences in fossils, we can trace evolutionary lineages and see how different species evolved from common ancestors. For example, the fossil record of horses shows a gradual change in body structure over time, indicating an evolutionary lineage.
• The body structures of ancient organisms: Fossils preserve the body structures of ancient organisms, so we can directly observe their anatomy.
• The options "The colorations and markings of ancient organisms" are not determinable from fossils as fossils do not preserve color or markings well, and "Sequential nature of ancient organisms" is not a typical conclusion from fossil study in the same way as the other three.

The similar general bone structure of the front leg of a frog and an alligator (homologous structures) indicates that they share evolutionary lineages from common ancestors. Homologous structures are structures that have a similar origin (from a common ancestor) but may have different functions.

Answer:

For the first blank (method to determine absolute age): radiometric dating
For the second blank (property of isotope used): half - life

Question 3 (Multiple Answer)