Question

section 1.

1. what was avery’s conclusion in 1944 at the end of his experiment?

1. dna is a long molecule made up of subunits(monomers) called __________________________.
2. what are the three basic components of a dna nucleotide?

1. what are the four nitrogenous bases in dna?

1. explain chargaff’s rules.

1. write the complementary dna strand using chargaff’s rules: attccgtgca

__________

1. which scientists discovered the structure of the dna molecule?

1. the structure of dna is called a _____________________________________.
2. label all the parts of the dna nucleotide correctly: sugar deoxyribose = (s), phosphate = (p), thymine = (t), and cytosine = (c).

dna nucleotide diagram with a, g, and various shapes representing parts

Explanation:

1. Avery concluded that DNA is the transforming principle.
2. DNA is made up of nucleotides.
3. A DNA nucleotide has a deoxyribose sugar, a phosphate group, and a nitrogenous base.
4. The four nitrogenous bases in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).
5. Chargaff's rules state that in DNA, the amount of adenine equals thymine (\(A = T\)) and the amount of cytosine equals guanine (\(C=G\)).
6. Using Chargaff's rules (\(A - T\) and \(C - G\) pairing), for the strand \(ATTCCGTGCA\), the complementary strand is \(TAAGGCACGT\).
7. James Watson and Francis Crick discovered the structure of the DNA molecule.
8. The structure of DNA is called a double - helix.
9. For the base \(A\) (adenine), its complementary base is \(T\) (thymine). For the base \(G\) (guanine), its complementary base is \(C\) (cytosine). So, the top complementary base (opposite \(A\)) is labeled \(T\) (using the key \(T=(T)\)) and the bottom complementary base (opposite \(G\)) is labeled \(C\) (using the key \(C=(C)\)). The sugar (\(S\)) is the pentagon - shaped structure and the phosphate (\(P\)) is the circular structure.

Answer:

1. DNA is the transforming principle.
2. nucleotides
3. deoxyribose sugar, phosphate group, nitrogenous base
4. adenine (A), thymine (T), cytosine (C), guanine (G)
5. In DNA, \(A = T\) and \(C = G\)
6. \(TAAGGCACGT\)
7. James Watson and Francis Crick
8. double - helix
9. Top complementary base (opposite \(A\)): \(T\); Bottom complementary base (opposite \(G\)): \(C\); Sugars (\(S\)): pentagon - shaped structures; Phosphates (\(P\)): circular structures.