nucleic acids

What is deoxyribonucleic acid (DNA)?

DNA is a macromolecule found in the nucleus of living cells that encodes proteins and is structured as a double helix.

What is the central dogma of molecular biology?

The flow of genetic information from DNA to RNA to protein.

What are the three processes involving DNA?

Transcription, Translation, and Replication.

What is the structure of DNA?

DNA consists of two strands of nucleotides arranged in a double helix, resembling a spiral staircase.

What are the three components of a nucleotide?

A phosphate group, a pentose sugar, and a nitrogenous base.

What is the difference between the sugars in DNA and RNA?

DNA contains deoxyribose, while RNA contains ribose.

What is a nucleoside?

A nucleoside is formed from a sugar and a nitrogenous base, without the phosphate group.

What type of bond forms between the pentose sugar and the nitrogenous base?

A β-N-glycosidic bond.

What bond forms between the nucleoside and the phosphate group?

A phosphoester bond.

What is a phosphodiester bond?

A bond that links the 3' carbon of one nucleotide to the 5' carbon of another, forming the sugar-phosphate backbone of DNA.

How do nucleotides join to form polynucleotides?

Nucleotides join via phosphodiester bonds to create a sugar-phosphate backbone.

What is the significance of the anti-parallel structure of DNA?

The two strands of DNA run in opposite directions, which is essential for replication and function.

Which nitrogenous bases pair together in DNA?

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

What type of bonds hold the two strands of DNA together?

Hydrogen bonds form between complementary nitrogenous bases.

What is the role of Erwin Chargaff in DNA research?

Chargaff discovered that the amount of adenine equals thymine and the amount of cytosine equals guanine in DNA.

What is the primary function of RNA?

RNA is involved in protein synthesis through transcription and translation.

What is the difference between RNA and DNA in terms of structure?

RNA is usually single-stranded and can take various shapes, while DNA is double-stranded and has a helical structure.

What is the complementary base for adenine in RNA?

Uracil (U) replaces thymine (T) found in DNA.

What is the significance of the 5' and 3' ends of a DNA molecule?

These ends indicate the directionality of the DNA strand, which is crucial for replication and transcription.

How does DNA replicate?

DNA replication involves unwinding the double helix and synthesizing new strands complementary to each original strand.

What is the role of messenger RNA (mRNA)?

mRNA carries the genetic code from DNA to the ribosome for protein synthesis.

What is the role of ribosomal RNA (rRNA)?

rRNA forms the core of ribosome structure and catalyzes protein synthesis.

What is the role of transfer RNA (tRNA)?

tRNA transports amino acids to the ribosome during protein synthesis, matching them to the mRNA code.

What is the significance of the double helix structure of DNA?

The double helix provides stability and protection for the genetic information encoded in the DNA.

What is the importance of the hydrogen bonds between base pairs?

Hydrogen bonds provide specificity and stability to the DNA structure, allowing for accurate base pairing.