Review Questions
4. Which of the following is not a feature common to most animals?
- development into a fixed body plan
- asexual reproduction
- specialized tissues
- heterotrophic nutrient sourcing
5. During embryonic development, unique cell layers develop into specific groups of tissues or organs during a stage called ________.
- the blastula stage
- the germ layer stage
- the gastrula stage
- the organogenesis stage
6. Which of the following phenotypes would most likely be the result of a Hox gene mutation?
- abnormal body length or height
- two different eye colors
- the contraction of a genetic illness
- two fewer appendages than normal
7. Which of the following organisms is most likely to be a diploblast?
- sea star
- shrimp
- jellyfish
- insect
8. Which of the following is not possible?
- radially symmetrical diploblast
- diploblastic eucoelomate
- protostomic coelomate
- bilaterally symmetrical deuterostome
9. An animal whose development is marked by radial cleavage and enterocoely is ________.
- a deuterostome
- an annelid or mollusk
- either an acoelomate or eucoelomate
- none of the above
10. Consulting the modern phylogenetic tree of animals, which of the following would not constitute a clade?
- deuterostomes
- lophotrochozoans
- Parazoa
- Bilateria
11. Which of the following is thought to be the most closely related to the common animal ancestor?
- fungal cells
- protist cells
- plant cells
- bacterial cells
12. As with the emergence of the Acoelomorpha phylum, it is common for ____ data to misplace animals in close relation to other species, whereas ____ data often reveals a different and more accurate evolutionary relationship.
- molecular : morphological
- molecular : fossil record
- fossil record : morphological
- morphological : molecular
13. Which of the following periods is the earliest during which animals may have appeared?
- Ordovician period
- Cambrian period
- Ediacaran period
- Cryogenian period
14. What type of data is primarily used to determine the existence and appearance of early animal species?
- molecular data
- fossil data
- morphological data
- embryological development data
15. The time between 542–488 million years ago marks which period?
- Cambrian period
- Silurian period
- Ediacaran period
- Devonian period
16. Until recent discoveries suggested otherwise, animals existing before the Cambrian period were believed to be:
- small and ocean-dwelling
- small and nonmotile
- small and soft-bodied
- small and radially symmetrical or asymmetrical
17. Plant life first appeared on land during which of the following periods?
- Cambrian period
- Ordovician period
- Silurian period
- Devonian period
18. Approximately how many mass extinction events occurred throughout the evolutionary history of animals?
- 3
- 4
- 5
- more than 5