Chapter 28 Protists

Question 1

Secondary Endosymbiosis

Answer 1

a process in eukaryotic evolution in which a heterotrophic eukaryotic cell engulfed a photosynthetic eukaryotic cell, which survived in a symbiotic relationship inside the heterotrophic cell

Question 2

Name the four monophyletic groups of protists

Answer 2

1) Excavates
2) SARs
3) Archaeplastida
4) Unikonts

Question 3

Excavates

Answer 3

• have an excavated groove on the side of the cell body
• have highly reduced mitochondria (mitosomes)
• have flagella that differ in structure from those of other organisms
• several are parasites

Question 4

SARs

Answer 4

• made up of three major clades: Stramenophiles, Alveolates, and Rhizarians
• Alveolates and Stramenophiles are photosynthetic and evolved from secondary endosymbiosis when a heterotrophic protist engulfed red algae
• Alveolates include pathogens
• Rhizarians include amoebas that have pseudopodia that are threadlike in shape

Question 5

Archaeplastida

Answer 5

• includes red algae, green algae, and plants

Question 6

Unikonts

Answer 6

• includes amoeba that have lobe or tube-shaped pseudopodia
• includes animals, fungi, and non-amoeba protists

Question 7

What are some indicators that secondary endosymbiosis occurred?

Answer 7

-Multiple membranes
-Plastids

Question 8

If protists are paraphyletic, what else is in the tree of Eukarya?

Answer 8

plants, animals, and fungi