EOC review evolution

A scientist studying the evolution of a species of sea scallop wrote the following description of its evolution:

“The fossil record shows several periods of rapid speciation. Each period spans several thousand years. The speciation periods are separated by hundreds of thousands of years where no changes were observed. During the short speciation periods, many different species evolved rapidly.”

The scientist concludes that the evidence supports one form of evolutionary change. Which form is BEST supported by the evidence cited?

• gradualism

• coevolution

• convergent evolution

• punctuated equilibrium

Which cellular organelle is thought to have evolved from a prokaryote that was able to use oxygen?

• chloroplast

• Golgi apparatus

• mitochondrion

• ribosome

Which of the following scenarios BEST illustrates that two organisms likely share a common ancestor?

• Ducks and platypuses both have developed bills for mouths.

• Yeast can use the human version of a yeast gene to repair itself.

• Arctic foxes and Arctic hares grow white coats as camouflage in winter.

• Protozoans can enter the bloodstream and multiply in the liver, causing malaria.

According to the endosymbiotic theory, the outer membrane of the chloroplast originated from which organelle?

• the lysosome of an engulfed prokaryotic cell

• the chloroplast of an engulfed prokaryotic cell

• the cell membrane of an eukaryotic host cell

• the chloroplast of an eukaryotic host cell

Which statement provides evidence that mitochondria MOST likely evolved when a primitive eukaryotic cell engulfed a prokaryotic bacteria?

• Both mitochondria and bacteria have a circular DNA molecule.

• Both mitochondria and bacteria have the same type of ribosomes.

• Both mitochondria and bacteria have a double-membrane nucleus.

• Both mitochondria and bacteria have the same amount of cytoplasm.

According to the fossil record, when did episodes of rapid speciation commonly take place?

• while Earth’s continents were joined

• while Earth’s habitats were stable

• before major climatic changes

• following mass extinctions

Which statement BEST explains why evolution is classified as a theory?

• It is a set of hypotheses supported by scientific findings.

• It has been proved by valid scientific experiments.

• It explains observations more simply than other available models.

• It is accepted by a majority of scientists working in relevant fields,

The discovery of a fossilized animal with teeth, a long bony tail, and feathered wings helped to establish which evolutionary sequence?

• rodents to bats

• reptiles to birds

• aquatic organisms to land-based organisms

• invertebrates to flying organisms

Fossil records indicate that species changes generally

• stop when a species forms.

• speed up with stable conditions.

• take place over many generations.

• are independent of the environment.

Rhinoceroses and horses are related. They have very similar digestive systems and an odd number of toes on their feet. Horses have one toe, and rhinoceroses have three. These facts BEST support which claim?

• Horses and rhinoceroses share a common ancestor.

• Horses and rhinoceroses are genetically identical.

• Horses are the ancestors of modern rhinoceroses.

• Horses have descended from modern rhinoceroses.