Name ______________________ Biology 112 – Quiz (Chapter 29)

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. All questions are worth 1 point.

1) Imagine there are 25 different species of protists living in a tide pool. Some of these species reproduce both sexually and asexually, and some of them can reproduce only asexually. Over the course of a year, the average water temperature of the tide pool increases significantly. Which species are more likely thrive in the changing environment?

A) the sexually reproducing species

B) the asexually reproducing species

2) Although the species diversity of protists is relatively low, their abundance is extraordinarily high. Why is the abundance of protists important?

a. Plankton fix nitrogen on the ocean floor.

b. The sugars protists produce are the basis of food chains in both freshwater and marine environments.

c. The protists that dominate marine plankton have short life spans.

d. The carbon-containing shells that surround some unicellular algae dissolve in ocean water after these organisms die.

3) Which of these characteristics best defines multicellularity?

a. Not all cells in a multicellular organism express the same genes.

b. The cells in the organism aggregate but perform the same function.

c. The cells in the organism exist independently of other cells.

d. The cells in the organism have hard external structures that provide support or protection.

4) In comparing protists to bacteria and archaea, which method of obtaining energy is unique to the protists?

a. absorbing reduced inorganic compounds from the environment

b. absorbing reduced organic compounds, such as sugars

c. ingesting other organisms, such as bacteria, archaea, and protists

d. photosynthesis

5) Why do some scientists believe that increasing populations of protists could help reduce global warming?

a. The calcium carbonate shells found in some protist lineages act as a long-term carbon sink.

b. The carbon contributed by protists to the global carbon cycle takes a short-term form that is used up rapidly.

c. Protists serve as the basis of aquatic food chains, which transfer chemical energy.

d. Increased respiration of larger protist populations releases more carbon dioxide into the ocean, which is then incorporated into marine food chains.