A1.2

Flashcards about Nucleic Acids, DNA, and RNA

What is the role of DNA and RNA as genetic material?

DNA is the genetic material of life, used as a blueprint for the production of building blocks. Some viruses use RNA as genetic material.

What are the components of a nucleotide?

A sugar with 5 carbon atoms (pentose sugar), an acidic phosphate group (negatively charged), and one of 4-5 different nitrogenous bases.

What is a nucleoside composed of?

The sugar and base.

What is a nucleotide composed of?

The sugar, base, and phosphate group.

What is the difference in sugar between DNA and RNA?

RNA has a ribose sugar, while DNA has a deoxyribose sugar.

How are nucleotides linked together to form a strand?

Individual nucleotides are linked together in long chains through a condensation reaction, forming covalent bonds with a sugar-phosphate backbone.

Describe the structure of DNA as a double helix.

Two strands that twist around each other in an antiparallel way, forming a double helix. Strands are made of nucleotides with a sugar-phosphate backbone. Bases join the two strands by hydrogen bonds.

What are the complementary base pairings in DNA?

Adenine pairs with Thymine, and Cytosine pairs with Guanine.

What is the role of complementary base pairing?

Ensures regular arrangement and geometry within the double helix and allows an exact copy to be made during replication.

What type of bonding facilitates complementary base pairing?

Hydrogen bonding between matching bases, specifically Guanine and Cytosine (3 H-bonds) and Adenine and Thymine (2 H-bonds).

How is genetic information stored and decoded?

The sequence of bases in DNA or RNA contains information in a coded form. This information is decoded during protein synthesis, where groups of three bases (codons) code for specific amino acids.

How does the universality of the genetic code support the theory of common ancestry?

Nearly all organisms have the same genetic code, suggesting a common ancestry. This is supported by successful genetic engineering across species.

Where is genetic information stored in DNA?

Genetic information is stored in the base sequence of a DNA strand, with any sequence of bases being possible. There are 4 different bases which can be arranged in any order: A, C, G, T

Evidence of universal common ancestry across all life forms stems from what?

Universal genetic code