What do constructions by earthworms help to do?
Options:
- (A) compact soil
- (B) moisten soil
- (C) agriculture
- (D) to move people
- (E) relocation
- (F) aerate soil
- (G) survival
- (H) dry out soil
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Let's think first: Earthworm burrows help aerate soil, which is also good for plants. Most species construct burrows. Constructions by earthworms help aerate soil which is good for plants.... So the answer is [(F)]

How are atolls built?
Options:
- (A) important habitats
- (B) By coral exoskeletons
- (C) by fish
- (D) with machines
- (E) by a type of eel
- (F) It used to be covered by water
- (G) The area was once underwater
- (H) reusing materials
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Let's think first: Many corals secrete an exoskeleton that builds up to become a coral reef. An atoll is the third type of reef. Atolls are built by corals secreting an exoskeleton.... So the answer is [(B)]

What is it called when male gametes are propelled because of muscle contractions?
Options:
- (A) competition
- (B) rapid expansion
- (C) intercourse
- (D) thrusting
- (E) a wave
- (F) reproductions
- (G) A Greek letter
- (H) ejaculation
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Let's think first: Ejaculation occurs when muscle contractions propel sperm from the epididymes. Male gametes are called sperm. Ejaculation occurs when muscle contractions propel male gametes from the epididymes.... So the answer is [(H)]

Cells have multiple repair mechanisms to fix mutations in what?
Options:
- (A) Veins and arteries.
- (B) Most plants
- (C) the body's largest organ
- (D) members of their own species
- (E) wavelengths and photons
- (F) epidermis and dermis
- (G) deoxyribonucleic acid
- (H) peachleaf willow
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Let's think first: Cells have multiple repair mechanisms to fix mutations in DNA. DNA DNA is deoxyribonucleic acid. Cells have multiple repair mechanisms to fix mutations in deoxyribonucleic acid.... So the answer is [(G)]

Viral envelopes are sometimes made of fats and what?
Options:
- (A) cellulose
- (B) glucose
- (C) Energy.
- (D) protein
- (E) viral particles
- (F) Energy
- (G) food
- (H) bacteria
--
Let's think first: Some viruses have an envelope of phospholipids and proteins. Phospholipids are body fats, too. Some viruses have an envelope of fats and proteins.... So the answer is [(D)]

What is one way billions of seeds be spread by?
Options:
- (A) wind
- (B) manufactured goods
- (C) fossilization
- (D) maples
- (E) range
- (F) Seesaw
- (G) hail
- (H) trees
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Let's think first: Spores may be dispersed by moving water, wind, or other organisms. Billions of spores can be produced on a single spore horn. Billions of seeds can be spread by moving wind, other organisms, or water.... So the answer is [(A)]