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complete the two dna molecules. how do these molecules compare to each other?

DNA molecules are typically represented as double helices with two complementary strands, where bases pair specifically: adenine (A) with thymine (T), and cytosine (C) with guanine (G). Completing a DNA molecule involves filling in the missing bases on a partial strand using these base-pairing rules to form a full double helix. Since no specific partial sequences were provided in the query, this explanation uses standard educational examples to demonstrate completion and comparison.

Example DNA Molecules

Consider these two incomplete single strands needing complementary partners:

  • Molecule 1 (Template): 5'-ATGCGT-3'
    Completed complementary strand: 3'-TACGC A-5' (full: 5'-ATGCGA-3' paired as A-T, T-A, G-C, C-G, G-C, T-A).

  • Molecule 2 (Template): 5'-GATCCA-3'
    Completed complementary strand: 3'-CTAGGT-5' (full: 5'-ACCTAG-3' paired as G-C, A-T, T-A, C-G, C-G, A-T).

Key Completion Steps

DNA completion mimics replication:

  1. Unzip the strands (helicase in vivo).
  2. Add RNA primer (primase).
  3. DNA polymerase adds nucleotides complementary to the template.
  4. Ligase seals gaps for a continuous strand.

Structural Comparison

Aspect| Molecule 1| Molecule 2| Notes
---|---|---|---
Length| 6 base pairs| 6 base pairs| Identical size in this example 1.
Base Sequence| ATGCGT / TACGCA| GATCCA / CTAGGT| Different sequences, no homology 46.
GC Content| 50% (3G/C)| 50% (3G/C)| Same stability potential 7.
Base Pairing| All standard (A-T, G-C)| All standard (A-T, G-C)| Follows Chargaff's rules 10.
Directionality| Antiparallel (5'-3' vs 3'-5')| Antiparallel (5'-3' vs 3'-5')| Universal DNA feature 1.

These molecules are not identical but complementary within themselves —each strand dictates the other's sequence. They differ entirely between molecules, like unique genes, yet share the same helical structure and pairing rules, enabling vast genetic diversity.

TL;DR: Completion uses A-T/G-C pairing; the two example molecules differ in sequence but match in structure and rules, just as real DNA strands vary across genes.

Information gathered from public forums or data available on the internet and portrayed here.