The first forms of life on Earth were thought to be_______.

1. single-celled plants
2. prokaryotes
3. insects
4. large animals such as dinosaurs

The first organisms that oxygenated the atmosphere were _______.

1. cyanobacteria
2. phototrophic organisms
3. anaerobic organisms
4. all of the above

Which of the following consist of prokaryotic cells?

1. bacteria and fungi
2. archaea and fungi
3. protists and animals
4. bacteria and archaea

Prokaryotes stain as Gram-positive or Gram-negative because of differences in the _______.

1. cell wall
2. cytoplasm
3. nucleus
4. chromosome

Prokaryotes that obtain their energy from chemical compounds are called _____.

1. phototrophs
2. auxotrophs
3. chemotrophs
4. lithotrophs

Bioremediation includes _____.

1. the use of prokaryotes that can fix nitrogen
2. the use of prokaryotes to clean up pollutants
3. the use of prokaryotes as natural fertilizers
4. All of the above

What event is thought to have contributed to the evolution of eukaryotes?

1. global warming
2. glaciation
3. volcanic activity
4. oxygenation of the atmosphere

Mitochondria most likely evolved from _____________.

1. a photosynthetic cyanobacterium
2. cytoskeletal elements
3. aerobic bacteria
4. membrane proliferation

Protists with the capabilities to absorb nutrients from dead organisms are called_____________.

1. photoautotrophs
2. autotrophs
3. saprobes
4. heterotrophs

Which parasitic protist evades the host immune system by altering its surface proteins with each generation?

1. Paramecium caudatum
2. Trypanosoma brucei
3. Plasmodium falciparum
4. Phytophthora infestans

Which polysaccharide is usually found in the cell walls of fungi?

1. starch
2. glycogen
3. chitin
4. cellulose

What term describes the close association of a fungus with the root of a tree?

1. a rhizoid
2. a lichen
3. a mycorrhiza
4. an endophyte