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What is 1 + 3?
Bond formed by two atoms sharing electrons
Molecule that has slightly positive and negative ends
A physical, chemical, or behavioral feature that helps an organism survive
Organisms that float on the surface of the water
Organisms that swim in the water column
Organisms that live on the bottom of a lake, stream, or ocean
The ability of an organism to keep its body in balance
Structures found in fish that help maintain oxygen/carbon dioxide balance
Roots that hold deep into mud
Roots that help plants that grow in stagnant water get air
Roots that help plants growing in salt water get fresh water