Question

miguel ramirez, edgardo 0/25-26 cms district biology unit 2 - summative #1 which statement correctly a basic structural unit of dna? 1: phosphate; 2: uracil; 3: ribose 1: phosphate; 2: adenine; 3: deoxyribose 1: phosphate; 2: adenine; 3: ribose 1: phosphate; 2: uracil; 3: deoxyribose

Explanation:

Step1: Recall DNA components

The basic structural unit of DNA is a nucleotide. A nucleotide has three parts: a phosphate group, a nitrogen - containing base, and a five - carbon sugar. The sugar in DNA is deoxyribose. The nitrogenous bases in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G). Uracil (U) is found in RNA, not DNA.

Step2: Analyze the options

In the given options, the correct combination for the parts of a DNA nucleotide corresponding to the diagram (where 1 is the phosphate group, 2 is a nitrogenous base, and 3 is the sugar) is phosphate, adenine (a DNA base), and deoxyribose (the DNA sugar).

Answer:

1: Phosphate; 2: Adenine; 3: Deoxyribose