DNA Structure and Replication

Flashcards based on lecture notes for DNA Structure and Replication, covering key concepts and details for exam preparation.

What is DNA and its function?

Deoxyribonucleic acid (DNA) is the hereditary molecule that serves as the instruction manual for building individuals and is passed from parents to offspring.

How many pairs of chromosomes do humans have?

Humans have 23 pairs of chromosomes, with one chromosome from each pair inherited from each parent.

What is the structure of DNA?

DNA is composed of two strands of nucleotides that twist to form a double helix, with sugars and phosphates forming the backbone and bases forming the rungs.

Which bases pair together in DNA?

Adenine (A) pairs with Thymine (T) and Guanine (G) pairs with Cytosine (C) in DNA.

What is DNA profiling?

DNA profiling is the analysis of a section of the genome to identify unique characteristics in a person's DNA, functioning like a molecular 'fingerprint.'

What role does the Polymerase Chain Reaction (PCR) play in DNA studies?

PCR is a technique used to amplify specific DNA segments to study them, allowing billions of copies from a starting sample.

Why are short tandem repeats (STRs) useful in DNA profiling?

STRs are repeated DNA sequences that vary in number from person to person, making them ideal for identifying unique DNA profiles.

What is the importance of DNA evidence in the legal system?

DNA evidence is highly reliable and more accurate than other forms of evidence, as no two individuals (except identical twins) share the exact same DNA.

What happens during DNA replication?

During DNA replication, the helicase enzyme unwinds the DNA strands, and DNA polymerase adds complementary nucleotides to form new strands.

What is the significance of complementary base pairing in DNA replication?

Complementary base pairing (A-T; G-C) guides the accurate copying of DNA sequences during replication.