Chapter 27: Protists

Biologists study protists because:

• they help understand the evolution and diversity of life.

• they are the largest group of animals.

• they are only found in extreme environments.

• they are responsible for all diseases.

The major themes in the diversification of protists include:

• Evolution of different modes of nutrition, locomotion, and reproduction

• Development of complex nervous systems

• Formation of multicellular tissues only

• Exclusive adaptation to terrestrial environments

The endosymbiosis theory explains how certain organelles in protists originated and relates to the evolution of multicellularity by suggesting that complex cells evolved from symbiotic relationships between simpler cells. Which statement best describes this theory?

• It proposes that complex cells evolved from symbiotic relationships between simpler cells, leading to multicellularity.

• It states that multicellularity in protists occurred through random mutations only.

• It suggests that all organelles in protists originated from viruses.

• It claims that multicellularity in protists is unrelated to symbiotic relationships.

Some key lineages of protists include which of the following?

• Amoebozoa, Excavata, SAR, Archaeplastida

• Chordata, Arthropoda, Mollusca, Echinodermata

• Bryophyta, Pteridophyta, Gymnosperms, Angiosperms

• Basidiomycota, Ascomycota, Zygomycota, Chytridiomycota

Some innovations in feeding, movement, and reproduction found in protists include:

• Pseudopodia, cilia, and conjugation

• Photosynthesis, multicellularity, and lungs

• Gills, wings, and internal fertilization

• Roots, stems, and flowers

Which of the following is a synapomorphy of Domain Eukarya?

• Cell wall

• Nuclear envelope

• Peptidoglycan

• Plasmid

Compared to Bacteria and Archaea, Eukaryotes are approximately how many times larger?

• 2 times

• 5 times

• 10 times

• 100 times

Eukaryotic cells have many _________.

• organelles

• nucleoids

• capsids

• flagella

Which structure is extensive in Eukaryotic cells?

• Cell wall

• Cytoskeleton

• Capsule

• Flagella

Multicellularity is common in Eukaryotes.

• True

• False