4 Written questions
3 Multiple choice questions
- they provide positional information in the embryo
- 4.5 billion years ago ... 3.9 billion years ago
- Ivy leaf and pine needle
3 True/False questions
Phylogeny is the evolutionary history of related groups of organisms. Organisms are grouped into taxa based on homologous characteristics, shared traits that result from common ancestry. Which statement is true?
Homologous structures look the same and serve the same function, but they differ in evolutionary origin and structure.
The term "monophyletic" refers to a taxon that includes an ancestral species and all of its descendants.
Ancestral traits are always simpler than derived traits. → The term "monophyletic" refers to a taxon that includes an ancestral species and all of its descendants.
Evolution works by _____.
"tinkering" with existing structures
predicting the future
molding the environment to conform to the organisms living in it
constantly increasing complexity
converging on a particular phenotype → "tinkering" with existing structures
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