Quiz Protists answers

1) What makes certain red algae appear red?

They possess pigments that reflect and transmit red light.

2) If blue light is the component of the visible spectrum that can penetrate to the greatest depth in water, then what should be expected of photosynthetic protists that survive at great depths?

They should absorb blue light preferentially.

3) According to the endosymbiotic theory of the origin of eukaryotic cells, how did mitochondria originate?

from engulfed, originally free-living prokaryotes

4) Which taxonomic group containing eukaryotic organisms is thought to be directly ancestral to the plant kingdom?

green algae

5) Which organisms represent the common ancestor of all photosynthetic plastids found in eukaryotes?

cyanobacteria

6) The following are all characteristic of the water molds (Oomycote) except

a feeding plasmodium.

7) Theoretically, which two of the following present the richest potential sources of silica?

2. diatomaceous earth

3. marine sediments consisting of radiolarian tests

8) The chloroplasts of modern plants are thought to have been derived according to which sequence?

cyanobacteria --> green algae --> green plants

9) A snail-like, coiled, porous shell of calcium carbonate is characteristic of which group?

foraminiferans

10) A mixotroph loses its plastids yet continues to survive. Which of the following most likely accounts for its continued survival?

It engulfs organic material by phagocytosis.

11) In ciliates, the process that produces genetic variation through the exchange of nuclei is

conjugation.

12) In life cycles with an alternation of generations, multicellular haploid forms alternate with

multicellular diploid forms.

13) Which protists form colorful, multinucleate masses?

plasmodial slime molds

14) The strongest evidence for the endosymbiotic origin of eukaryotic organelles is the similarity between extant prokaryotes and which of the following?

mitochondria and chloroplasts

15) The goal in classifying organisms should be to create categories that reflect the evolutionary histories of organisms. What system would be best to use?

a system that uses as many kingdoms as necessary to be accurate

16) A large seaweed that floats freely on the surface of deep bodies of water would be expected to lack which of the following?

holdfasts

17) Organisms classified as Euglenozoa have previously been classified as protozoans, protista, plants, and animals. Why the confusion?

Like protozoans, they are unicellular.

Like animals, many are heterotrophic.

Like plants, many are photosynthetic.

18) Which of the following marine organisms produce potent neurotoxins that cause extensive fish kills, contaminate shellfish, and create severe respiratory irritation to humans along the shore?

dinoflagellates

19) A paramecium is a

ciliate.

20) A certain unicellular eukaryote has a siliceous (glasslike) shell and autotrophic nutrition. To which group does it belong?

diatom

21) The largest seaweeds belong to which group?

brown algae

22) Protists are alike in that all are

eukaryotic.