Question

name: chelsea english period: 8th date: 11/9/25 dna structure review on the lines provided, complete the following sentences. 1. the letters dna stand for: ____________________________. 2. the structure of a dna molecule can be described as a __________________________. 3. dna is made up of repeating units (monomers) called __________________________. 4. these monomers are comprised of three parts: ____________, ____________ and ____________. 5. if a dna molecule is made up of 30% adenine bases, what percentage of bases will be thymine? ____________ 6. what percentage would be guanine? ____________. 7. the backbone of dna is comprised of ____________________________.

Explanation:

1. DNA is an abbreviation for Deoxyribonucleic Acid.
2. The double - helix structure is a well - known characteristic of DNA.
3. Nucleotides are the building blocks (monomers) of DNA.
4. Each nucleotide consists of a phosphate group, a deoxyribose sugar, and a nitrogenous base.
5. According to Chargaff's rules, adenine pairs with thymine. If adenine is 30%, thymine is also 30%.
6. Since adenine + thymine = 60%, the remaining 40% is for guanine and cytosine. And guanine pairs with cytosine, so guanine is 20%.
7. The backbone of DNA is made up of alternating sugar (deoxyribose) and phosphate groups.

Answer:

1. Deoxyribonucleic Acid
2. double - helix
3. nucleotides
4. phosphate group; deoxyribose sugar; nitrogenous base
5. 30%
6. 20%
7. alternating sugar (deoxyribose) and phosphate groups