HSC Biology Practice Exam 2025 – The Complete Guide to Mastering Your Biology Exam Success!

Question: 1 / 400

What base pairs with adenine (A) in DNA structure?

Cytosine (C)

Guanine (G)

Thymine (T)

Adenine (A) pairs with thymine (T) in the structure of DNA through two hydrogen bonds. This pairing is essential for the formation of the double-helix structure of DNA, as it ensures fidelity during DNA replication and transcription. The complementary base pairing (A with T and cytosine with guanine) allows for the accurate transmission of genetic information. This is critical for cell division and the synthesis of proteins, as the sequence of bases ultimately determines the traits of an organism. The pairing of adenine and thymine is a foundational aspect of the Watson-Crick model of DNA.

Other options, while they represent nucleobases, do not correctly pair with adenine in the context of DNA: cytosine pairs with guanine, while uracil is found in RNA, not DNA.

Get further explanation with Examzify DeepDiveBeta

Uracil (U)

Next Question

Report this question

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy