Scientific investigations often lead to the formulation of specific questions. The observations Charles Darwin’s work after he returned home from his voyage prompted to ask which questions

Cold case files recently began re-investigating an old murder case. the murder took place in the park; a young man, james, was hit over the head with a brick and killed. police suspected the jealous former boyfriend of james' wife, karen. whoever killed james may have washed their hands in a near-by bird bath as detectives found blood in the bird bath. since the murder took place before dna fingerprinting was available, the suspected killer, ronnie, went free. detectives are now reviewing the blood evidence using dna fingerprinting. based on the dna fingerprints of all possible suspects, who is james' killer?

Drag the tiles to the correct boxes to complete the pairs. match the nitrogenous base of dna with its complement.

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.