4 Written questions
3 Multiple choice questions
- "tinkering" with existing structures
- they showed that organic molecules such as amino acids could be produced from inorganic molecules
3 True/False questions
Radiometric dating _____.
allows us to determine an absolute, errorless date
only works on rocks younger than 75,000 years
allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata
relies on the fact that the daughter isotope decays to the parent isotope at a constant rate
can be used to directly date fossils in sedimentary rock → allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata
Why do some scientists believe that RNA, rather than DNA, was the first genetic material?
All the proto-cells on early Earth contained RNA.
RNA has both information storage and catalytic properties.
RNA could have evolved into DNA.
RNA can replicate more accurately than DNA.
RNA contains uracil in place of thymine → RNA has both information storage and catalytic properties.
Earth probably formed _____ years ago, and the first life evolved as early as _____ years ago.
4.5 billion years ago ... 3.9 billion years ago
Humans observed neither event, so there is no way to tell.
6,000 years ago ... 6,000 years ago
3.9 million years ago ... 2.0 billion years ago
10 billion years ago ... 4.5 billion years ago → they provide positional information in the embryo