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Found Base 12 times.

Displaying results 1 to 10.

1. Base
Any basic (alkaline) compound containing nitrogen , but generally referring to one of four complex molecules ( nucleotide s) that form the building blocks of the nucleic acids, DNA and RNA .

2. Base (alkali, Bronsted base, Arrhenius base, Lewis base)
A fundamental category of many compounds whose water-based solutions have a bitter taste, a slippery feel in water, turn red litmus paper blue, and can react with acid s to form salts. A base has a pH higher than 7; a strong base will have a pH of 13 or higher. Specific types of bases include: * Arrhenius base: any chemical that increases the number of free hydroxide ion s (OH-) when they're added to a water-based solution. The more ions produced, the stronger the acid. * Bronsted or Bronsted-Lowry base: any chemical that acts as a proton acceptor in a chemical reaction. * Lewis base: any chemical that donates two electrons to form a covalent bond during a chemical reaction.

3. Base analog
A chemical which resembles a nucleotide base . A base which does not normally appear in DNA but can substitute for the ones which do, despite minor differences in structure.

4. Base composition
In reference to nucleic acid, the proportion of the total bases consisting of guanine plus cytosine or thymine plus adenine base pairs. Usually expressed as a guanine + cytosine (G+C) value, e.g. 60% G+C.

5. Base dissociation constant (base ionization constant)
This is the equilibrium constant for the reaction in which a weak base breaks apart in water to form its conjugate acid and hydroxide (-OH) ion.

6. Base flow (sustaining flow, normal flow, ordinary flow, groundwater flow)
The portion of the stream discharge that is derived from natural storage (e.g., groundwater outflow and the draining of large lakes and swamps or other source outside the net rainfall that creates surface runoff); discharge sustained in a stream channel, not as a result of direct runoff and without the effects of regulation, diversion, or other works of man.

7. Base pair (bp)
Two nitrogenous bases ( adenine and thymine or guanine and cytosine ) held together by weak bonds. Two strands of DNA are held together in the shape of a double helix by the bonds between base pairs.

8. Base sequence
The order of nucleotide bases in a DNA molecule.

9. Base sequence analysis
A method, sometimes automated, for determining the base sequence .

10. Base substitution
One nucleotide base is replaced by another in a DNA molecule. This is also called a point mutation .

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