Exam 1: Biology and the Tree of Life

Algae in the genus Caulerpa typically grow to a length of over half a meter and have structures similar to stems,leaves,and roots.Reproduction occurs when adults produce sperm and eggs that fuse to form offspring.Each adult Caulerpa,however,consists of just a single cell.Which of the following statements is true?

Recall Pasteur's experiment on spontaneous generation.Originally,he used sealed and unsealed flasks instead of swan-necked and unsealed flasks.Critics claimed that the experiment was inconclusive.Which of the following criticisms would be addressed by using a swan-necked flask instead of the sealed flask?

Environments all over the world are changing as a result of global warming.Could this influence natural selection?

Which of the following observations lead to the conclusion that the food competition hypothesis for giraffe neck length might not be correct?

What hypothesis was being tested in the initial experiment with open versus sealed jars?

Which one of the following predictions follows from the sexual selection hypothesis for why giraffes have long necks?

On an evolutionary tree,any group that includes a common ancestor and all of its descendants is called monophyletic ("one-tribe").Draw the tree for Bacteria,Archaea,and Eukarya.Are prokaryotes monophyletic?

Why was it important that Redi replicate each treatment four times in each experiment?

On an evolutionary tree,any group that includes a common ancestor and all of its descendants is called monophyletic ("one-tribe").Draw the tree for Bacteria,Archaea,and Eukarya that we think best represents the current data.According to this tree,are all organisms alive today monophyletic?

Over the past several decades,natural selection has caused populations of Staphylococcus aureus (an infectious wound bacterium)to evolve resistance to most antibiotics.If antibiotic use were stopped,what would you predict would happen to these S.aureus populations?

How does artificial selection differ from natural selection?

What do the nodes and branch points on a phylogenetic tree represent?

Which of the following best reflects a phylogenetic conclusion regarding chimpanzees and baboons?

How does a scientific theory differ from a scientific hypothesis?

Louis Pasteur's experiment had a good design because