15.2 assessment answers

What types of evidence do scientist’s use to argue for evolution? comparative embryology, anatomy, biochemistry; geographical distribution and fossil record 2. What is a transitional fossil? fossils that gives us information about a transition from one species to another

3. Describe the differences between derived traits and ancestral traits found in transitional fossils. Ancestral traits are primitive features that appear in the ancestor of species Derived traits are newly evolved traits that do not appear in the ancestral fossil

4. What are three types of structures used as evidence in comparative anatomy? Vestigial, analogous, homologous

Describe the differences between all three structures. vestigial – reduced form of structure that one functioned in the organism Analogous – structures with same function but a different structure Homologous – similar structure but have a different function

6. What is an example of a vestigial structure in humans? appendix 7. What have scientist’s concluded from comparing embryo’s between species? vertebrate embryos have homologous structures in early development but become totally different structures in the adult forms

8. What is an example of a complex metabolic molecule in organisms? Amino acids, proteins, DNA 9. Scientist’s that the more closely related species are, the greater____________ of sequences of amino acids will be shared. number

10. Describe the geographic observations Darwin discovered about species in South America. animals on the South American mainland were more similar to other South American animals than they were to animals living in similar environments in Europe

11. Why did islands have more different plant species than animal diversity? migration What is biogeography? study of the distribution of plants and animals on Earth

13. What are three factors that help explain ancestral relationships and the distribution of fossils around the world today? Climate, plate tectonics, and geological forces

14. Describe the difference between reproductive success and fitness 14. Describe the difference between reproductive success and fitness. reproductive success – passing of genes on to the next generation so that they may pass the genes on to their offspring Fitness is the number of (living) offspring that an organism produces in the next generation.

15. What are two examples of adaptation discussed in class? Camouflage mimcry

Honors 16. Explain why vestigial structures are considered examples of homologous structures? When the vestigial structure was functioning it was a similar structure in a related species so it would be classified as homologous

17. How do mimicry and camouflage increase the fitness of a species 17. How do mimicry and camouflage increase the fitness of a species? Fitness of a species is the number of living offspring produced so these adaptations will lead to survival will also the number of offspring produced.

18. How would an albino of a species that is normally green and lives among leaves be less fit? He is not able to blend in to the environment and will not survive to reproduce.

Research has shown that if a prescribed dose of antibiotic is not take completely, some bacteria might not be killed and the disease might return. How does natural selection explain this phenomenon? Some of the bacteria have a variation that allows it to survive the antibiotic. When these bacteria divide, this population will be resistant to the antibiotic. It is important to take all the medication to get rid of all the bacteria before it can become resistant.

What can be concluded from the fact that many insects are resistant to certain pesticides. Insects are usually susceptible to pesticides. Natural selection selects for those that could survive the pesticide so that they are now resistant to it.