Problem:OPTIONS:
- characteristics
- the body's largest organ
- watery habitat
- centralized nervous system
- functioning arm
- underwater life
- biological diversity
- epidermis and dermis

Fact 1: Echinoderms lack a centralized nervous system. Fact 2: Echinoderms include starfish, sea urchins, and sea cucumbers. Given the two facts above, starfish, sea urchins and sea cucumbers lack a what?
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A: centralized nervous system

Problem:OPTIONS:
- nucleus
- epidermal
- Joules
- alveoli
- glucose
- Epidermis
- oxygen
- PDAs

Fact 1: Prokaryotes are single-celled organisms that lack a nucleus. Fact 2: Prokaryotes have no membrane-bound organelles, thus bacteria are prokaryotic organisms. Given the two facts above, bacteria have no membrane-bound organelles and lack what?
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A: nucleus

Problem:OPTIONS:
- oxygen
- gas
- rain
- sugar
- heat
- water
- energy
- Energy.

Fact 1: Transpiration is when water vapor moves from plants into the atmosphere. Fact 2: Plants lose water continually by transpiration. Given the two facts above, what do plants lose to the atmosphere?
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A: water

Problem:OPTIONS:
- humans
- consumers
- Airplane technicians
- Dehydrated Apricots
- Preserved Strawberries
- space travel
- athletes
- Crewmembers

Fact 1: Astronauts require preserved food for extended flights. Fact 2: Crewmembers are astronauts Virgil 1. Given the two facts above, who requires preserved food for extended flights?
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A:
Crewmembers