Exam 29: Protists

Consider the following data: (a)Most ancient eukaryotes are unicellular.(b)All eukaryotes alive today have a nucleus and cytoskeleton.(c)Most ancient eukaryotes lack a cell wall.Which of the following conclusions could reasonably follow the data presented?

A particular species of protist lacks the ability to engulf food and does not contain chloroplasts.However,gene sequencing data indicate that this species evolved from a lineage containing many species with the ability to engulf food.What does this information suggest about this species of protist?

Cultures of the same species of diatom referred to in the previous question were treated with BDM,a reversible inhibitor of myosin function.Which of the following predictions is consistent with the hypothesis that an actin-myosin interaction is necessary for motility?

Consider the following points: (a)All excavates live in environments where oxygen availability is low;(b)all excavates lack mitochondria;and (c)all excavates have some mitochondrial genes.Based on this information,which of the following statements is true of the excavate lineage?

Protists belong to the domain Eukarya.Which of the following is not a protist?

Which of the following characteristics is true of all protists?

Figure 29.2 -Refer to the figure above and consider the following data: Brown algae (protists)include unicellular and multicellular organisms.Red algae (protists)include unicellular and multicellular organisms.Amoebae (protists)include unicellular and multicellular organisms.Which of the following conclusions is consistent with the data presented?

Latrunculin A is a reversible toxin that disrupts the formation of actin fibers.A culture of a particular species of diatom was treated with this toxin diluted in a buffer,while another culture was treated only with the buffer (no toxin;control).The motility of cells in each culture was assessed by counting the number of cells that were moving during a defined period of time.Which of the following conclusion statements is reasonable based on the data in the bar graph presented below?

Encouraging the growth (via nutrient fertilization)of photosynthetic protists in marine environments may help reduce global warming.Why?

According to the endosymbiotic theory,why was it adaptive for the larger (host)cell to keep the engulfed cell alive,rather than digesting it as food?

Which of the following would be considered a carbon sink that could potentially reduce atmospheric carbon dioxide to help alleviate global warming?

Which of the following groups is matched with an incorrect anatomical feature?

Which of the major lineages of eukaryotes contain pronounced "feeding grooves" for digesting prey or organic debris?

Assume that some members of an aquatic species of motile,photosynthetic protists evolve to become parasitic to fish.They gain the ability to live in the fish gut,absorbing nutrients as the fish digests food.Over time,which of the following phenotypic changes would you expect to observe in this population of protists?

The structure of protist flagella indicates that this structure evolved directly from the bacterial flagella.

The dinoflagellate Pfiesteria piscicida can feed off algae and bacteria.They can also "steal" intact chloroplasts from algae and become photosynthetic.In the presence of large amounts of fish,Pfiesteria can secrete a toxin that kills fish,allowing it to feed on decaying fish matter.How would you classify this species?

You discover a new lineage of protists.You examine several species of this lineage under the microscope and find a distinctive feature that sets them apart from other protists.Following the nomenclature style used to name the lineage Discicristata,you decide to name this new lineage Spherocristata.What is the distinctive feature that is reflected in the name?

Which of the following observations about flagella is true and is consistent with the scientific conclusion that the flagella from protists and bacteria evolved independently?

How was primary productivity measured in the phytoplankton experiment?

Which of the following statements is consistent with the assertion that protists are paraphyletic?