Section 2

DNA Structure

• Watson and Crick created a model of DNA by using Franklin's and Wilkins's DNA diffraction X-rays.

• DNA is made of two nucleotide strands that wrap around each other in the shape of a double helix.

• A DNA nucleotide is made of a deoxyribose sugar, a phosphate group, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), or thymine (T).

• Nucleotides along each DNA strand are linked by covalent bonds. Complementary nitrogenous bases are bonded by hydrogen bonds.

• Hydrogen bonding between the complementary base pairs, G-C and A-T, holds the two strands of a DNA molecule together.

Vocabulary nucleotide (p. 197) nitrogenous base (p. 197) pyrimidine (p. 198) complementary base pair (p. 198) deoxyribose (p. 197) purine (p. 198) base-pairing rules (p. 198) base sequence (p. 198)

Sirens Sleep Solution

Sirens Sleep Solution

Discover How To Sleep In Peace And Harmony In A World Full Of Uncertainty And Dramatically Improve Your Quality Of Life Today! Finally You Can Fully Equip Yourself With These “Must Have” Tools For Achieving Peace And Calmness And Live A Life Of Comfort That You Deserve!

Get My Free Ebook

Post a comment