(Slide Questions/Padlot) Chapter 25: The History of Life on Earth - Incomplete

Why do some scientists believe that RNA, rather than DNA, was the first genetic material?

RNA has both information storage and catalytic properties

What features might we expect the mitochondria and chloroplasts in eukaryotic cells to contain if these organelles were the result of endosymbiosis of bacterial cells?

plasma membrane, DNA, and ribosomes

Photosynthesis eukaryotes contain both mitochondria and chloroplasts. Which sequence of events most likely describes the evolution of this group?

Ancestral anaerobic prokaryote engulfs an aerobic heterotrophic prokaryote and then engulfs a photosynthetic prokaryote

Which of the following organelles likely originated from endosymbiosis

chloroplasts and mitochondria

A species of birds finds its way to the Galapagos islands, where there are several ecological niches. This species evolves into many new species to fill all the unfilled niches. This is an example of

adaptive radiation

Carbon-14 is a commonly used isotope for radiometric dating. It decays to nitrogen-14 with a half-life of 5,700 years. A biological sample is found to have 1/16 as much C-14 as there is in the atmosphere. How old is the sample?

22,800 years

The Cambrain explosion marks the relatively "sudden" appearance of many animal phyla approximately 542 million years ago. Approximately what percentage of Earth's history has occurred before the appearance of animals?

87%

The following are four hypothesized stages of the origin of life. Place them in the correct order.

1. Origin of self-replicating molecules
2. Joining of organic monomers into polymers
3. Abiotic synthesis of small organic monomers
4. Packaging of molecules into membranous proto-cells

3, 2, 4, 1

Which of the following pieces of evidence is not considered to be supportive of the endosymbiont theory?

Chloroplasts and mitochondria have organic molecules

When did the mass extinction that eliminated most dinosaurs occur?

66 million years ago

The many finch species on the Galapagos Islands arose through adaptive radiation. Which piece of evidence would best support this claim?

The Galapagos finch species are more closely related to each other genetically than they are to non-Galapagos finches

Which of the following statements helps explain the origin of new structures like eyes or wings?

a. New evolutionary structures require new genes

b. new evolutionary structures can arise from changes in the expression of existing genes

c. new structures can evolve in stepwise fashion

d. structures evolved in one context can be co-opted for another function

e. all of the above

all of the above

Which of the following evolutionary novelties is most consistent with being facilitated by a Hox gene?

wing number in insects