10.15–10.18: An overview of the diversity of life on earth: organisms are divided into three domains.

All life on earth can be divided into three domains–bacteria, archaea, and eukarya–which reflect species’ evolutionary relatedness to each other.

Question 10.24

The mass extinction that occurred on earth 65 million years ago was immediately followed by:

  • a) the rise of archaea.
  • b) the emergence of the first non-photosynthetic organisms.
  • c) the rise of the reptiles, including the dinosaurs.
  • d) an increase in atmospheric oxygen levels.
  • e) the rapid divergence and radiation of modern mammals.

Question 10.25

Prokaryotes are classified into ________ domain(s).

  • a) 1
  • b) 2
  • c) 3
  • d) 4
  • e) 5

Question 10.26

All protists are alike in that all are:

  • a) bacterial.
  • b) photosynthetic.
  • c) eukaryotic.
  • d) prokaryotic.
  • e) archaeal.

Question 10.27

Which of the following pairs of domains share the most recent common ancestor?

  • a) archaea and eukarya
  • b) bacteria and eukarya
  • c) archaea and bacteria
  • d) None of the above; all three domains evolved from different ancestors.
  • e) None of the above; all three domains are equally related to each other.

Question 10.28

Which of the following groups would be placed nearest the fungi in an evolutionary tree based on DNA sequences?

  • a) plants
  • b) bacteria
  • c) animals
  • d) archaea
  • e) protists