question: What have varied life cycles?
Options:
- (A) bacteria
- (B) fungi
- (C) Variety.
- (D) Cycles.
- (E) plants
- (F) Plants.
- (G) insects
- (H) Life of air.
answer: Algae have varied life cycles. Some, such as the green algae, are plants. Some plants have varied life cycles.
The answer is (F)

question: What do all chemical changes require to occur?
Options:
- (A) during the day
- (B) heating liquids
- (C) Activation energy
- (D) wavelengths and photons
- (E) Burning fuel and air
- (F) kinetic energy
- (G) electromagnetic energy
- (H) direct energy
answer: All chemical reactions require activation energy to get started. Chemical changes are a result of chemical reactions. All chemical changes require activation energy to occur.
The answer is (C)

question: What are not cells at all, so they are neither prokaryotes nor eukaryotes?
Options:
- (A) Something with a head, thorax, and abdomen
- (B) Microscopic organisms
- (C) The smallest agent of disease
- (D) Dead prehistoric beings
- (E) female sex cells
- (F) major threat to health
- (G) remains of prehistoric life
- (H) Something that smells like rotten eggs
answer: Viruses are not cells at all, so they are neither prokaryotes nor eukaryotes. Viruses Viruses are the smallest agents of disease. The smallest agents of disease are not cells at all, so they are neither prokaryotes nor eukaryotes.
The answer is (C)

question: What process helps provide resources for producers to create food?
Options:
- (A) animals
- (B) Exfoliation
- (C) decomposition
- (D) mastication
- (E) recycling
- (F) reproduction
- (G) ejaculation
- (H) Converting waste.
answer:
Producers use energy and inorganic molecules to make food. Decomposition is the breakdown of organic molecules into inorganic molecules. Decomposition provides resources for producers to create food.
The answer is (C)