DNA Structure and Replication

DNA Structure and Replication

• Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C) in DNA.
• DNA replication is semi-conservative, meaning each new DNA molecule contains one original strand and one newly synthesized strand.
• Helicase is the enzyme responsible for separating the two strands of DNA during replication.
• DNA's structure is known as a double helix.

DNA Components

• Deoxyribose sugar: a five-carbon sugar that forms the backbone of DNA.
• Phosphate group: a negatively charged group that attaches to the sugar molecules.
• Nitrogenous bases: adenine (A), thymine (T), guanine (G), and cytosine (C), which carry the genetic information.

DNA Mutations and Significance

• DNA mutations are changes in the sequence of DNA.
• Mutations can be harmful, beneficial, or neutral.
• Harmful mutations can cause diseases, while beneficial mutations can lead to evolutionary adaptations.

DNA Replication Processes

• Okazaki fragments are formed on the lagging strand during replication, not the leading strand.
• DNA polymerase is responsible for adding new nucleotides to the growing DNA chain during replication, ensuring accuracy.

mRNA Vaccines

• The primary purpose of mRNA vaccines is to instruct the body's cells to produce proteins that trigger an immune response against a specific pathogen, like a virus.

Central Dogma of Molecular Biology

• The Central Dogma of Molecular Biology states that DNA makes RNA through transcription, and RNA makes proteins through translation.

Transcription and Translation Processes

• Transcription is the process of creating RNA from a DNA template.
• Translation is the process of creating proteins from RNA.
• Pre-mRNA undergoes processing before leaving the nucleus, including capping, polyadenylation, and splicing.

Transcription Steps

• Initiation: RNA polymerase binds to the promoter region of the DNA.
• Elongation: RNA polymerase moves along the DNA template, adding complementary RNA nucleotides to create mRNA.
• Termination: RNA polymerase reaches a termination sequence on the DNA and releases the mRNA molecule.

Alternative Splicing

• Alternative splicing allows a single gene to produce multiple proteins by selectively including or excluding specific exons from the final mRNA transcript.

RNA Polymerase in Transcription

• RNA polymerase is the enzyme responsible for synthesizing RNA from the DNA template during transcription.

Explore the fundamental concepts of DNA structure and the process of DNA replication. Learn about nucleotide bases, the double helix formation, and how cells duplicate their DNA. This quiz will test your understanding of these essential biological principles.