Question

What DNA sequence is complementary to the following sequence? \(\mathrm{A}-\mathrm{G}-\mathrm{T}-\mathrm{T}-\mathrm{C}-\mathrm{A}-\mathrm{T}-\mathrm{C}-\mathrm{G}\)

Short answer

The complementary DNA sequence is T-C-A-A-G-T-A-G-C.

Step-by-step solution

Understand Base Pairing Rules

To find the complementary DNA sequence, we need to understand the base pairing rules in DNA: 1. Adenine (A) pairs with Thymine (T). 2. Thymine (T) pairs with Adenine (A). 3. Guanine (G) pairs with Cytosine (C). 4. Cytosine (C) pairs with Guanine (G). These rules will help us find the complementary bases for each nucleotide in the given sequence.

Find Complement for Each Base

Go through each base in the given sequence and find its complement using the base pairing rules: - A (Adenine) pairs with T (Thymine). - G (Guanine) pairs with C (Cytosine). - T (Thymine) pairs with A (Adenine). - T (Thymine) pairs with A (Adenine). - C (Cytosine) pairs with G (Guanine). - A (Adenine) pairs with T (Thymine). - T (Thymine) pairs with A (Adenine). - C (Cytosine) pairs with G (Guanine). - G (Guanine) pairs with C (Cytosine).

Write the Complementary Sequence

Using the complementary bases found in Step 2, write out the complementary DNA sequence to the original DNA sequence: Original Sequence: A-G-T-T-C-A-T-C-G Complementary Sequence: T-C-A-A-G-T-A-G-C

Key concepts

DNA sequence

In the realm of genetics, a DNA sequence is like a blueprint for life. It consists of a series of nucleotides arranged in a specific order, each containing one of four bases: adenine (A), thymine (T), cytosine (C), and guanine (G).
These bases form the alphabet of our genetic code. DNA sequences direct biological functions, from protein synthesis to genetic inheritance. Each sequence is vital for understanding how organisms develop and thrive. The order of nucleotides within a DNA sequence determines the information available for building and maintaining an organism.

The sequence runs in a 5' to 3' direction, ensuring consistency in reading the genetic information. You can think of this direction as how you read a sentence from left to right. Despite their simplicity, DNA sequences carry instructions for life itself, making them a fundamental aspect of biology.

complementary bases

Complementary bases refer to pairs of nucleotides that form bonds with one another, creating the classic double-helix structure of DNA. Their pairing is essential for DNA replication and function.
Think of them as fitting together like pieces of a puzzle. The key pairs include:

• Adenine (A) with Thymine (T)
• Thymine (T) with Adenine (A)
• Guanine (G) with Cytosine (C)
• Cytosine (C) with Guanine (G)

These specific pairings occur due to hydrogen bonds, creating a stable structure that can withstand various cellular processes. Complementary base pairing ensures accurate replication, so our genetic information is preserved each time cells divide.
In the context of finding a complementary DNA sequence, each base on the original strand has a predetermined partner on the opposite strand. This natural pairing is key for replicating and repairing DNA accurately.

nucleotide pairing

Nucleotide pairing is crucial to understanding how DNA strands interact and maintain stability. Each nucleotide in a DNA strand consists of a sugar, a phosphate group, and a nitrogenous base (A, T, C, or G). The process of nucleotide pairing involves matching specific bases on one DNA strand with their complementary bases on the opposing strand. This assures the proper transfer and storage of genetic information.

Here's how it works in practice:

• Adenine (A) forms a pair with Thymine (T) through two hydrogen bonds.
• Guanine (G) pairs with Cytosine (C) through three hydrogen bonds, making this pair slightly stronger.

These pairs ensure every time a cell divides, each new cell receives an exact copy of DNA. This process is crucial for growth, repair, and replication of organisms. Understanding nucleotide pairing is critical for many fields in biology and medicine, including genetic engineering and hereditary research. It’s the basis for technologies like PCR (polymerase chain reaction), used to replicate DNA molecules efficiently.